what is importance of physical education in your life

Physical education for healthier, happier, longer and more productive living

The time children and adults all over the world spend engaging in physical activity is decreasing with dire consequences on their health, life expectancy, and ability to perform in the classroom, in society and at work.

In a new publication, Quality Physical Education, Guidelines for Policy Makers , UNESCO urges governments and educational planners to reverse this trend, described by the World Health Organization (WHO) as a pandemic that contributes to the death of 3.2 million people every year, more than twice as many as die of AIDS.

The Guidelines will be released on the occasion of a meeting of UNESCO’s Intergovernmental Committee for Physical Education and Sport (CIGEPS) in Lausanne, Switzerland, (28-30 January).*

UNESCO calls on governments to reverse the decline in physical education (PE) investment that has been observed in recent years in many parts of the world, including some of the wealthiest countries. According to European sources, for example, funding and time allocation for PE in schools has been declining progressively over more than half of the continent, and conditions are not better in North America.

The new publication on PE, produced in partnership with several international and intergovernmental organizations**, advocates quality physical education and training for PE teachers. It highlights the benefits of investing in PE versus the cost of not investing (cf self-explanatory infographics ).

“The stakes are high,” says UNESCO Director-General Irina Bokova. “Public investment in physical education is far outweighed by high dividends in health savings and educational objectives. Participation in quality physical education has been shown to instil a positive attitude towards physical activity, to decrease the chances of young people engaging in risky behaviour and to impact positively on academic performance, while providing a platform for wider social inclusion.”

The Guidelines seek to address seven areas of particular concern identified last year in UNESCO’s global review of the state of physical education , namely: 1. Persistent gaps between PE policy and implementation; 2. Continuing deficiencies in curriculum time allocation; 3. Relevance and quality of the PE curriculum; 4. Quality of initial teacher training programmes; 5. Inadequacies in the quality and maintenance of facilities; 6. Continued barriers to equal provision and access for all; 7. Inadequate school-community coordination.

The recommendations to policy-makers and education stake-holders are matched by case studies about programmes, often led by community-based nongovernmental organizations. Success stories in Africa, North and Latin America, Asia and Europe illustrate what can be achieved by quality physical education: young people learn how to plan and monitor progress in reaching a goal they set themselves, with a direct impact on their self-confidence, social skills and ability to perform in the classroom.

While schools alone cannot provide the full daily hour of physical activity recommended for all young people, a well-planned policy should promote PE synergies between formal education and the community. Experiences such as Magic Bus (India) which uses physical activity to help bring school drop outs back to the classroom highlight the potential of such school-leisure coordination.

The publication promotes the concept of “physical literacy,” defined by Canada’s Passport for Life organization of physical and health educators as the ability to move “with competence and confidence in a wide variety of physical activities in multiple environments that benefit the healthy development of the whole person. Competent movers tend to be more successful academically and socially. They understand how to be active for life and are able to transfer competence from one area to another. Physically literate individuals have the skills and confidence to move any way they want. They can show their skills and confidence in lots of different physical activities and environments; and use their skills and confidence to be active and healthy.”

For society to reap the benefit of quality physical education, the guidelines argue, planners must ensure that it is made available as readily to girls as it is to boys, to young people in school and to those who are not.

The Guidelines were produced at the request of UNESCO’s Intergovernmental Committee for Physical Education and Sport (CIGEPS) and participants at the Fifth International Conference of Ministers and Senior Officials Responsible for Physical Education and Sport (Berlin 2013). UNESCO and project partners will proceed to work with a number of countries that will engage in a process of policy revision in this area, as part of UNESCO’s work to support national efforts to adapt their educational systems to today’s needs (see Quality physical education contributes to 21st century education ).

Media contact: Roni Amelan, UNESCO Press Service, r.amelan(at)unesco.org , +33 (0)1 45 68 16 50

Photos are available here: http://www.unesco.org/new/en/media-services/multimedia/photos/photo-gallery-quality-physical-education/

* More about the CIGEPS meeting

** The European Commission, the International Council of Sport Science and Physical Education (ICSSPE), the International Olympic Committee (IOC), UNDP, UNICEF, UNOSDP and WHO.

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Chapter: 3 physical activity and physical education: relationship to growth, development, and health.

Physical Activity and Physical Education: Relationship to Growth, Development, and Health

Key Messages

• Regular physical activity promotes growth and development and has multiple benefits for physical, mental, and psychosocial health that undoubtedly contribute to learning.

• Specifically, physical activity reduces the risk for heart disease, diabetes mellitus, osteoporosis, high blood pressure, obesity, and metabolic syndrome; improves various other aspects of health and fitness, including aerobic capacity, muscle and bone strength, flexibility, insulin sensitivity, and lipid profiles; and reduces stress, anxiety, and depression.

• Physical activity can improve mental health by decreasing and preventing conditions such as anxiety and depression, as well as improving mood and other aspects of well-being.

• Physical activity programming specifically designed to do so can improve psychosocial outcomes such as self-concept, social behaviors, goal orientation, and most notably self-efficacy. These attributes in turn are important determinants of current and future participation in physical activity.

• Sedentary behaviors such as sitting and television viewing contribute to health risks both because of and independently of their impact on physical activity.

• Health-related behaviors and disease risk factors track from childhood to adulthood, indicating that early and ongoing opportunities for physical activity are needed for maximum health benefit.

• To be effective, physical activity programming must align with the predictable developmental changes in children’s exercise capacity and motor skills, which affect the activities in which they can successfully engage.

• Frequent bouts of physical activity throughout the day yield short-term benefits for mental and cognitive health while also providing opportunities to practice skills and building confidence that promotes ongoing engagement in physical activity.

• Distinct types of physical activity address unique health concerns and contribute in distinct ways to children’s health, suggesting that a varied regimen including aerobic and resistance exercise, structured and unstructured opportunities, and both longer sessions and shorter bouts will likely confer the greatest benefit.

T he behaviors and traits of today’s children, along with their genetics, are determinants of their growth and development; their physical, mental, and psychosocial health; and their physical, cognitive, and academic performance. Technological advances of modern society have contributed to a sedentary lifestyle that has changed the phenotype of children from that of 20 years ago. Children today weigh more and have a higher body mass index (BMI) than their peers of just a generation earlier (Ogden et al., 2012). Behaviorally, most children fail to engage in vigorous- or moderate-intensity physical activity for the recommended 60 minutes or more each day, with as many as one-third reporting no physical activity in the preceding 5 days (CDC, 2012). This lack of participation in physical activity has contributed to a greater prevalence of pediatric obesity, a decrease in fitness (e.g., flexibility, muscular strength, cardiorespiratory capacity), and a greater risk for disease (Boreham and Riddoch, 2001; Eisenmann, 2003; Malina, 2007; Steele et al., 2008). (See Box 3-1 for an overview of the relationship between physical activity and physical fitness.)

Physical Activity and Physical Fitness

As noted in Chapter 1 (see the box titled “Key Terms Used in This Report” on p. 17), physical activity, a behavior, is defined as bodily movement that increases energy expenditure, whereas fitness is a physiologic trait, commonly defined in terms of cardiorespiratory capacity (e.g., maximal oxygen consumption), although other components of fitness have been defined (IOM, 2012b). Exercise, a subset of physical activity, is “planned, structured and repetitive” (Carpersen et al., 1985, p. 128) and designed to target a particular outcome, for example, cardiorespiratory capacity or another component of fitness. Physical education provides opportunities for developmentally appropriate physical activity, usually structured to promote motor skill development, fitness, and health.

The relationship between physical activity and physical fitness is complex and bidirectional. Numerous studies have shown a significant relationship between physical activity and cardiorespiratory fitness, which may mean that physical activity improves fitness or that physically fit individuals choose to engage in physical activity more than their less fit peers, or both. Experimental studies have shown that exercise training improves fitness (Malina et al., 2004), although the response is variable and clearly influenced by genetics (Bouchard, 2012), and physical activity and fitness are independently related to health and academic performance (see the figure below).

Conceptual framework illustrating relationships among physical activity, physical fitness, health, and academic performance.

While more can always be learned, the evidence for the health benefits of physical activity is irrefutable (HHS, 1996, 2008). Adults engaged in regular physical activity have lower rates of chronic disease (e.g., coronary heart disease, cardiovascular disease, type 2 diabetes, hypertension, osteoporosis, and some cancers) and are less likely to die prematurely (HHS, 1996, 2008; Bauman, 2004). And while the ill effects of chronic disease are manifested mainly in adults, it is increasingly better understood that the development of these conditions starts in childhood and adolescence (Hallal et al., 2006; Cook et al., 2009; Halfon et al., 2012). It appears evident, then, that promotion of health-enhancing behaviors must also start early in life. Indeed, growing evidence points to long-term effects of child and adolescent physical activity on adult morbidity and mortality in addition to its more immediate effects (Hallal et al., 2006) (see Figure 3-1 ).

FIGURE 3-1 Conceptual model of how physical activity in childhood and adolescence is beneficial to health. Physical activity has both immediate and long-term health benefits: (a) Physical activity tends to track; early physical activity is associated with physical activity in subsequent life stages. (b) Physical activity reduces morbidity risk in childhood and adolescence. (c) Physical activity may be important in treating and slowing some diseases in children and adolescents. (d) Early physical activity influences future morbidity (e.g., physical activity in childhood and adolescence may reduce fracture risk later in life). SOURCE: Adapted from Hallal et al., 2006.

ship of physical activity and aerobic fitness to health during childhood, it is important first to recognize the developmental changes that occur throughout maturation. During the early stages of adolescence, for example, participation in physical activity and corresponding physical fitness begin to decline (Duncan et al., 2007). Such differences across stages of development highlight the importance of examining the effects of growth and maturation on physical and cognitive health. Accordingly, this chapter reviews how physical activity may influence developmental processes and other aspects of somatic growth and maturation. A complete review of the effects of physical activity on all tissues and systems is beyond the scope of this report. Rather, the focus is on components of body composition and systems that underlie engagement in physical activity, physical fitness, and chronic disease risk and that in turn influence other aspects of health and academic performance (discussed in Chapter 4 ). Addressed in turn is the relationship between physical activity and physical, psychosocial, and mental health. Structural and functional brain maturation and how physical activity may influence those developmental processes and cognitive health are also reviewed in Chapter 4 .

PHYSICAL HEALTH

This section reviews what is known about the relationship between physical activity and (1) somatic growth, development, and function and (2) health- and performance-related fitness.

Somatic Growth, Development, and Function

Growth occurs through a complex, organized process characterized by predictable developmental stages and events. Although all individuals follow the same general course, growth and maturation rates vary widely among individuals. Just as it is unrealistic to expect all children at the same age to achieve the same academic level, it is unrealistic to expect children at the same age to have the same physical development, motor skills, and physical capacity. Regular physical activity does not alter the process of growth and development. Rather, developmental stage is a significant determinant of motor skills, physical capacity, and the adaptation to activity that is reasonable to expect (see Box 3-2 ).

Developmental Stages

Growth, Development, and Maturation

Growth is the normal process of increase in size as a result of accretion of tissues characteristic of the organism; growth is the dominant biological activity for most of the first two decades of life. Changes in size are the outcome of an increase in cell number (hyperplasia), an increase in cell size (hypertrophy), and an increase in intercellular substances (accretion).

Development

Encompassing growth and maturation, development denotes a broader concept; when used in a biological context, development refers to differentiation and specialization of stem cells into different cell types, tissues, organs, and functional units. Development continues as different systems become functionally refined. Development also refers to the acquisition and refinement of behavior relating to competence in a variety of interrelated domains, such as motor competence and social, emotional, and cognitive competence.

Maturation is the timing and tempo of progress toward the mature state and varies considerably among individuals; variation in progress toward the mature state over time implies variation in the rate of change. Two children may be the same size but at different points on the path to adult size or maturity.

hood, which includes the preschool years, and middle childhood, which includes the elementary school years, into the 5th or 6th grade. Adolescence is more difficult to define because of variation in its onset and termination, although it is commonly defined as between 10 and 18 years of age (WHO, 1986). The rapid growth and development of infancy continue during early childhood, although at a decelerating rate, whereas middle childhood is a period of slower, steady growth and maturation. Differences between boys and girls are relatively small until adolescence, which is marked by accelerated growth and attainment of sexual maturity (Tanner, 1962).

Across developmental stages, neurological development and control of movement advance in cephalocaudal and proximodistal directions; that is, they advance “head to toe” (cephalocaudal) and “midline to periphery” (proximodistal), while predictable changes in body proportions also occur. For example, the head accounts for 25 percent of recumbent length in an infant and only 15 percent of adult height, while the legs account for 38 percent of recumbent length at birth and 50 percent of adult height. These changes in body proportions occur because body parts grow at different rates. From birth to adulthood, as the head doubles in size, the trunk triples in length, and arm and leg lengths quadruple.

Coincident with these changes in body proportions, and in part because of them, the capacity to perform various motor tasks develops in a predictable fashion. For example, running speed increases are consistent with the increase in leg length. Neurological development also determines skill progression. Young children, for example, when thrown a ball, catch it within the midline of the body and do not attempt to catch it outside the midline or to either side of the body. As proximodistal development proceeds, children are better able to perform tasks outside their midline, and by adolescence they are able to maneuver their bodies in a coordinated way to catch objects outside the midline with little effort.

Physically active and inactive children progress through identical stages. Providing opportunities for young children to be physically active is important not to affect the stages but to ensure adequate opportunity for skill development. Sound physical education curricula are based on an understanding of growth patterns and developmental stages and are critical to provide appropriate movement experiences that promote motor skill development (Clark, 2005). The mastery of fundamental motor skills is strongly related to physical activity in children and adolescents (Lubans et al., 2010) and in turn may contribute to physical, social, and cognitive development. Mastering fundamental motor skills also is critical to fostering physical activity because these skills serve as the foundation for more advanced and sport-specific movement (Clark and Metcalfe, 2002; Hands et al., 2009; Robinson and Goodway, 2009; Lubans et al., 2010). Physical activity programs, such as physical education, should be based on developmentally appropriate motor activities to foster self-efficacy and enjoyment and encourage ongoing participation in physical activity.

Biological Maturation

these indicators of maturity to be similar. Skeletal maturity is typically assessed from radiographs of the bones in the hand and wrist; it is not influenced by habitual physical activity. Similarly, age at peak height velocity (the most rapid change in height), an indicator of somatic maturity, is not affected by physical activity, nor is the magnitude of peak height velocity, which is well within the usual range in both active and inactive youth. Discussions of the effects of physical activity on sexual maturation more often focus on females than males and, in particular, on age at menarche (first menses). While some data suggest an association between later menarche and habitual physical activity (Merzenich et al., 1993), most of these data come from retrospective studies of athletes (Clapp and Little, 1995). Whether regular sports training at young ages before menarche “delays” menarche (later average age of menarche) remains unclear. While menarche occurs later in females who participate in some sports, the available data do not support a causal relationship between habitual physical activity and later menarche.

Puberty is the developmental period that represents the beginning of sexual maturation. It is marked by the appearance of secondary sex characteristics and their underlying hormonal changes, with accompanying sex differences in linear growth and body mass and composition. The timing of puberty varies, beginning as early as age 8 in girls and age 9 in boys in the United States and as late as ages 13-15 (NRC/IOM, 1999). Recent research suggests that the onset of puberty is occurring earlier in girls today compared with the previous generation, and there is speculation that increased adiposity may be a cause (Bau et al., 2009; Rosenfield et al., 2009). Conversely, some data suggest that excess adiposity in boys contributes to delayed sexual maturation (Lee et al., 2010). Pubescence, the earliest period of adolescence, generally occurs about 2 years in advance of sexual maturity. Typically, individuals are in the secondary school years during this period, which is a time of decline in habitual physical activity, especially in girls. Physical activity trends are influenced by the development of secondary sex characteristics and other physical changes that occur during the adolescent growth spurt, as well as by societal and cultural factors. Research suggests that physical inactivity during adolescence carries over into adulthood (Malina, 2001a,b; CDC, 2006).

It is critical that adolescents be offered appropriate physical activity programs that take into account the physical and sociocultural changes they are experiencing so they will be inspired to engage in physical activity for a lifetime. As discussed below, adequate physical activity during puberty may be especially important for optimal bone development and prevention of excess adiposity, as puberty is a critical developmental period for both the skeleton and the adipose organ.

Adolescence is the transitional period between childhood and adulthood. The adolescent growth spurt, roughly 3 years of rapid growth, occurs early in this period. An accelerated increase in stature is a hallmark, with about 20 percent of adult stature being attained during this period. Along with the rapid increase in height, other changes in body proportions occur that have important implications for sports and other types of activities offered in physical education and physical activity programs. As boys and girls advance through puberty, for example, biacromial breadth (shoulder width) increases more in boys than in girls, while increases in bicristal breadth (hip width) are quite similar. Consequently, hip-shoulder width ratio, which is similar in boys and girls during childhood, decreases in adolescent boys while remaining relatively constant in girls (Malina et al., 2004). Ratios among leg length, trunk length, and stature also change during this period. Prior to adolescence, boys have longer trunks and shorter legs than girls (Haubenstricker and Sapp, 1980). In contrast, adolescent and adult females have shorter legs for the same height than males of equal stature. Body proportions, particularly skeletal dimensions, are unlikely to be influenced by physical activity; rather, body proportions influence performance success, fitness evaluation, and the types of activities in which a person may wish to engage. For example, there is evidence that leg length influences upright balance and speed (Haubenstricker and Sapp, 1980). Individuals who have shorter legs and broader pelvises are better at balancing tasks than those with longer legs and narrower pelvises, and longer legs are associated with faster running times (Dintiman et al., 1997). Also, longer arms and wider shoulders are advantageous in throwing tasks (Haubenstricker and Sapp, 1980), as well as in other activities in which the arms are used as levers. According to Haubenstricker and Sapp (1980), approximately 25 percent of engagement in movement-related activities can be attributed to body size and structure.

Motor Development

Motor development depends on the interaction of experience (e.g., practice, instruction, appropriate equipment) with an individual’s physical, cognitive, and psychosocial status and proceeds in a predictable fashion across developmental periods. Clark and Metcalfe (2002) provide an eloquent metaphor—“the mountain of motor development”—to aid in understanding the global changes seen in movement across the life span. Early movements, critical for an infant’s survival, are reflexive and dominated by biology, although environment contributes and helps shape reflexes. This initial reflexive period is followed quickly by the preadapted period , which begins when an infant’s movement behaviors are no longer reflexive and ends when the infant begins to apply basic movement skills (e.g.,

crawling, rolling, standing, and walking) that generally are accomplished before 12 months of age. The period of fundamental motor patterns occurs approximately between the ages of 1 and 7 years, when children begin to acquire basic fundamental movement skills (e.g., running, hopping, skipping, jumping, leaping, sliding, galloping, throwing, catching, kicking, dribbling, and striking). Practice and instruction are key to learning these skills, and a great deal of time in elementary school physical education is devoted to exploration of movement. Around age 7, during the so-called context-specific period of motor development, children begin to refine basic motor skills and combine them into more specific movement patterns, ultimately reaching what has been called skillfulness . Compensation , the final period of motor development, occurs at varying points across the life span when, as a result of aging, disease, injury, or other changes, it becomes necessary to modify movement.

While all children need not be “expert” in all movement skills, those who do not acquire the fundamental motor skills will likely experience difficulty in transitioning their movement repertoire into specific contexts and engagement in physical activity (Fisher et al., 2005; Barnett et al., 2009; Cliff et al., 2009; Robinson et al., 2012). A full movement repertoire is needed to engage in physical activities within and outside of the school setting. Thus, beyond contributing to levels of physical activity, physical education programs should aim to teach basic fundamental motor skills and their application to games, sports, and other physical activities, especially during the elementary years (i.e., the fundamental motor patterns and context-specific periods). At the same time, it is important to be mindful of the wide interindividual variation in the rate at which children develop motor skills, which is determined by their biological makeup, their rate of physical maturation, the extent and quality of their movement experiences, and their family and community environment.

An increasing amount of evidence suggests that people who feel competent in performing physical skills remain more active throughout their lives (Lubans et al., 2010). Conversely, those who are less skilled may be hesitant to display what they perceive as a shortcoming and so may opt out of activities requiring higher levels of motor competence (Stodden et al., 2008). Children who are less physically skillful tend to be less active than their skillful counterparts (Wrotniak et al., 2006; Williams et al., 2008; Robinson et al., 2012) and thus have a greater risk of overweight and obesity (Graf et al., 2004). Fundamental skills are the building blocks of more complex actions that are completed in sports, physical activities, and exercise settings. For example, throwing is a fundamental skill that is incorporated into the context-specific throw used in activities such as handball, softball, and water polo. Fundamental skills are of primary interest to both physical education teachers and coaches, and physical

education classes should be designed to challenge learners to develop their motor skills.

In 1998 the Centers for Disease Control and Prevention’s (CDC’s) Division of Nutrition and Physical Activity organized a workshop to determine future directions for research on physical activity. The workshop convened 21 experts from a wide range of academic disciplines. One recommendation resulting from the proceedings was for future research to describe the temporal relationship between motor development and physical activity (Fulton et al., 2001), signifying the importance of better understanding of the nature of the relationship between motor competence and physical activity. The assumption of this relationship is implied in multiple models of motor development (Seefeldt, 1980; Clark and Metcalfe, 2002; Stodden et al., 2008), which emphasize the importance of motor competence as a prerequisite for engagement in physical activity throughout the life span.

Two models that are commonly used to examine this relationship are Seefeldt’s (1980) hierarchical order of motor skills development and the dynamic association model of Stodden and colleagues (2008). Seefeldt proposed a hierarchical order of motor skills development that includes four levels: reflexes, fundamental motor skills, transitional motor skills (i.e., fundamental motor skills that are performed in various combinations and with variations and that are required to participate in entry-level organized sports, such as throwing for distance, throwing for accuracy, and/or catching a ball while in motion), and specific sports skills and dances. With improved transitional motor skills, children are able to master complex motor skills (e.g., those required for playing more complex sports such as football or basketball). At the end of this developmental period, children’s vision is fully mature. The progression through each level occurs through developmental stages as a combined result of growth, maturation, and experience. Seefeldt hypothesized the existence of a “proficiency barrier” between the fundamental and transitional levels of motor skills development. If children are able to achieve a level of competence above the proficiency barrier, they are more likely to continue to engage in physical activity throughout the life span that requires the use of fundamental motor skills. Conversely, less skilled children who do not exceed the proficiency barrier will be less likely to continue to engage in physical activity. Thus, it is assumed that “a confident and competent mover will be an active mover” (Clark, 2005, p. 44). For example, to engage successfully in a game of handball, baseball, cricket, or basketball at any age, it is important to reach a minimum level of competence in running, throwing, catching, and striking. The assumption of the existence of a relationship between motor competence and physical activity is at the “heart of our physical education programs” (Clark, 2005, p. 44). A thorough understanding of how this

relationship changes across developmental stages is crucial for curriculum development and delivery and teaching practices.

Lubans and colleagues (2010) recently examined the relationship between motor competence and health outcomes. They reviewed 21 studies identifying relationships between fundamental motor skills and self-worth, perceived physical competence, muscular and cardiorespiratory fitness, weight status, flexibility, physical activity, and sedentary behavior. Overall, the studies found a positive association between fundamental motor skills and physical activity in children and adolescents, as well as a positive relationship between fundamental motor skills and cardiorespiratory fitness. Other research findings support the hypothesis that the most physically active preschool-age (Fisher et al., 2005; Williams et al., 2008; Robinson et al., 2012), elementary school–age (Bouffard et al., 1996; Graf et al., 2004; Wrotniak et al., 2006; Hume et al., 2008; Lopes et al., 2011), and adolescent (Okely et al., 2001) youth are also the most skilled.

An advantage of the “proficiency barrier” hypothesis proposed by Seefeldt (1980) is its recognition that the relationship between motor competence and physical activity may not be linear. Rather, the hypothesis suggests that physical activity is influenced when a certain level of motor competence is not achieved and acknowledges that below the proficiency barrier, there is bound to be substantial variation in children’s motor competence and participation in physical activity. The proficiency barrier is located between the fundamental and transitional motor skills periods. The transition between these two levels of motor competence is expected to occur between the early and middle childhood years. Stodden and colleagues (2008) suggest that the relationship between motor competence and physical activity is dynamic and changes across time. In their model the “development of motor skill competence is a primary underlying mechanism that promotes engagement in physical activity” (p. 290).

ity. The literature supports this hypothesis, as indicated by low to moderate correlations between motor skills competence and physical activity

in preschool (Sääkslahti et al., 1999; Williams et al., 2008; Cliff et al., 2009; Robinson and Goodway, 2009; Robinson, 2011) and early elementary school–age (Raudsepp and Päll, 2006; Hume et al., 2008; Morgan et al., 2008; Houwen et al., 2009; Ziviani et al., 2009; Lopes et al., 2011) children.

In older children, perceived competence is more closely related to actual motor skills competence. Older, low-skilled children are aware of their skills level and are more likely to perceive physical activity as difficult and challenging. Older children who are not equipped with the necessary skills to engage in physical activity that requires high levels of motor skills competence may not want to display their low competence publicly. As children transition into adolescence and early adulthood, the relationship between motor skills competence and physical activity may strengthen (Stodden et al., 2008). Investigators report moderate correlations between motor skills competence and physical activity in middle school–age children (Reed et al., 2004; Jaakkola et al., 2009). Okely and colleagues (2001) found that motor skills competence was significantly associated with participation in organized physical activity (i.e., regular and structured experiences related to physical activity) as measured by self-reports. A strength of the model of Stodden and colleagues (2008) is the inclusion of factors related to psychosocial health and development that may influence the relationship between motor skills competence and physical activity, contributing to the development and maintenance of obesity. Other studies have found that perceived competence plays a role in engagement in physical activity (Ferrer-Caja and Weiss, 2000; Sollerhed et al., 2008).

Motor skills competence is an important factor; however, it is only one of many factors that contribute to physical activity. For instance, three studies have reported negative correlations between girls’ motor competence and physical activity (Reed et al., 2004; Cliff et al., 2009; Ziviani et al., 2009), suggesting that sex may be another determining factor. A possible explanation for these findings is that since girls tend to be less active than boys, it may be more difficult to detect differences in physical activity levels between high- and low-skilled girls. It is also possible that out-of-school opportunities for physical activity are more likely to meet the interests of boys, which may at least partially explain sex differences in physical activity levels (Le Masurier et al., 2005). Previous research suggests that in general boys are more motor competent than girls (Graf et al., 2004; Barnett et al., 2009; Lopes et al., 2011) and that this trend, which is less apparent in early childhood, increases through adolescence (Thomas and French, 1985; Thomas and Thomas, 1988; Thomas, 1994), although one study reports that girls are more motor competent than boys (Cliff et al., 2009).

One component of motor competence is the performance of gross motor skills, which are typically classified into object control and

locomotor skills. Consistent evidence suggests that boys are more competent in object control skills, while girls are more competent in locomotor skills (McKenzie et al., 2004; Morgan et al., 2008; Barnett et al., 2009). In light of these sex differences, it is important to examine the relationships of object control and locomotor skills with physical activity separately for boys and girls. For boys, object control skills are more related to physical activity than are locomotor skills (Hume et al., 2008; Morgan et al., 2008; Williams et al., 2008; Cliff et al., 2009), whereas evidence suggests that the reverse is true for girls (McKenzie et al., 2002; Hume et al., 2008; Cliff et al., 2009; Jaakkola et al., 2009). Three studies report a significant relationship between balance and physical activity for girls but not boys (Reed et al., 2004; Ziviani et al., 2009). Cliff and colleagues (2009) suggest that object control and locomotor skills may be more related to boys’ and girls’ physical activity, respectively, because of the activity type in which each sex typically engages.

The relationship between motor competence and physical activity clearly is complex. It is quite likely that the relationship is dynamic and that motor competence increases the likelihood of participating in physical activity while at the same time engaging in physical activity provides opportunities to develop motor competence (Stodden et al., 2008). Despite some uncertainty, the literature does reinforce the important role of physical education in providing developmentally appropriate movement opportunities in the school environment. These opportunities are the only means of engaging a large population of children and youth and providing them with the tools and opportunities that foster health, development, and future physical activity.

Regular physical activity has no established effect on linear growth rate or ultimate height (Malina, 1994). Although some studies suggest small differences, factors other than physical activity, especially maturity, often are not well controlled. It is important to note that regular physical activity does not have a negative effect on stature, as has sometimes been suggested. Differences in height among children and adolescents participating in various sports are more likely due to the requirements of the sport, selection criteria, and interindividual variation in biological maturity than the effects of participation per se (Malina et al., 2004).

Body Weight

Saris et al., 1986; Beunen et al., 1992; Lohman et al., 2006;), except in very obese children and adolescents. Similarly, physique, as represented in somatotypes, does not appear to be significantly affected by physical activity during growth (Malina et al., 2004). In contrast, components of weight can be influenced by regular physical activity, especially when the mode and intensity of the activity are tailored to the desired outcome. Much of the available data in children and adolescents is based on BMI, a surrogate for composition, and indirect methods based on the two-compartment model of body composition in which body weight is divided into its fat-free and fat components (Going et al., 2012). While studies generally support that physical activity is associated with greater fat-free mass and lower body fat, distinguishing the effects of physical activity on fat-free mass from expected changes associated with growth and maturation is difficult, especially during adolescence, when both sexes have significant growth in fat-free mass. The application of methods based on the two-compartment model is fraught with errors, especially when the goal is to detect changes in fat-free mass, and no information is available from these methods regarding changes in the major tissue components of fat-free mass—muscle and skeletal tissue.

Muscle Skeletal muscle is the largest tissue mass in the body. It is the main energy-consuming tissue and provides the propulsive force for movement. Muscle represents about 23-25 percent of body weight at birth and about 40 percent in adults, although there is a wide range of “normal” (Malina, 1986, 1996). Postnatal muscle growth is explained largely by increases in cell size (hypertrophy) driving an increase in overall muscle mass. The increase in muscle mass with age is fairly linear from young childhood until puberty, with boys having a small but consistent advantage (Malina, 1969, 1986). The sex difference becomes magnified during and after puberty, driven primarily by gender-related differences in sex steroids. Muscle, as a percentage of body mass, increases from about 42 percent to 54 percent in boys between ages 5 and 11, whereas in girls it increases from about 40 percent to 45 percent between ages 5 and 13 and thereafter declines (Malina et al., 2004). It should be noted that absolute mass does not decline; rather, the relative decline reflects the increase in the percentage of weight that is fat in girls. At least part of the sex difference is due to differences in muscle development for different body regions (Tanner et al., 1981). The growth rate of arm muscle tissue during adolescence in males is approximately twice that in females, whereas the sex difference in the growth of muscle tissue in the leg is much smaller. The sex difference that develops during puberty persists into adulthood and is more apparent for the musculature of the upper extremities.

Sex-related differences in muscular development contribute to differences in physical performance. Muscle strength develops in proportion to the cross-sectional area of muscle, and growth curves for strength are essentially the same as those for muscle (Malina and Roche, 1983). Thus the sex difference in muscle strength is explained largely by differences in skeletal muscle mass rather than muscle quality or composition. Aerobic (endurance) exercise has little effect on enhancing muscle mass but does result in significant improvement in oxygen extraction and aerobic metabolism (Fournier et al., 1982). In contrast, numerous studies have shown that high-intensity resistance exercise induces muscle hypertrophy, with associated increases in muscle strength. In children and adolescents, strength training can increase muscle strength, power, and endurance. Multiple types of resistance training modalities have proven effective and safe (Bernhardt et al., 2001), and resistance exercise is now recommended for enhancing physical health and function (Behringer et al., 2010). These adaptations are due to muscle fiber hypertrophy and neural adaptations, with muscle hypertrophy playing a more important role in adolescents, especially in males. Prior to puberty, before the increase in anabolic sex steroid concentrations, neural adaptations explain much of the improvement in muscle function with exercise in both boys and girls.

Skeleton The skeleton is the permanent supportive framework of the body. It provides protection for vital organs and is the main mineral reservoir. Bone tissue constitutes most of the skeleton, accounting for 14-17 percent of body weight across the life span (Trotter and Peterson, 1970; Trotter and Hixon, 1974). Skeletal strength, which dictates fracture risk, is determined by both the material and structural properties of bone, both of which are dependent on mineral accrual. The relative mineral content of bone does not differ much among infants, children, adolescents, and adults, making up 63-65 percent of the dry, fat-free weight of the skeleton (Malina, 1996). As a fraction of weight, bone mineral (the ash weight of bone) represents about 2 percent of body weight in infants and about 4-5 percent of body weight in adults (Malina, 1996). Bone mineral content increases fairly linearly with age, with no sex difference during childhood. Girls have, on average, a slightly greater bone mineral content than boys in early adolescence, reflecting their earlier adolescent growth spurt. Boys have their growth spurt later than girls, and their bone mineral content continues to increase through late adolescence, ending with greater skeletal dimensions and bone mineral content (Mølgaard et al., 1997). The increase in total body bone mineral is explained by both increases in skeletal length and width and a small increase in bone mineral density (Malina et al., 2004).

Many studies have shown a positive effect of physical activity on intermediate markers of bone health, such as bone mineral content and density.

Active children and adolescents have greater bone mineral content and density than their less active peers, even after controlling for differences in height and muscle mass (Wang et al., 2004; Hind and Burrows, 2007; Tobias et al., 2007). Exercise interventions support the findings from observational studies showing beneficial effects on bone mineral content and density in exercise participants versus controls (Petit et al., 2002; Specker and Binkley, 2003), although the benefit is less than is suggested by cross-sectional studies comparing active versus inactive individuals (Bloomfield et al., 2004). The relationship between greater bone mineral density and bone strength is unclear, as bone strength cannot be measured directly in humans. Thus, whether the effects of physical activity on bone mineral density translate into similar benefits for fracture risk is uncertain (Karlsson, 2007). Animal studies have shown that loading causes small changes in bone mineral content and bone mineral density that result in large increases in bone strength, supporting the notion that physical activity probably affects the skeleton in a way that results in important gains in bone strength (Umemura et al., 1997). The relatively recent application of peripheral quantitative computed tomography for estimating bone strength in youth has also provided some results suggesting an increase in bone strength with greater than usual physical activity (Sardinha et al., 2008; Farr et al., 2011).

The intensity of exercise appears to be a key determinant of the osteogenic response (Turner and Robling, 2003). Bone tissue, like other tissues, accommodates to usual daily activities. Thus, activities such as walking have a modest effect at best, since even relatively inactive individuals take many steps (>1,000) per day. Activities generating greater muscle force on bone, such as resistance exercise, and “impact” activities with greater than ordinary ground reaction forces (e.g., hopping, skipping, jumping, gymnastics) promote increased mineralization and modeling (Bloomfield et al., 2004; Farr et al., 2011). Far fewer randomized controlled trials (RCTs) examining this relationship have been conducted in children than in adults, and there is little evidence on dose response to show how the type of exercise interacts with frequency, intensity, and duration. Taken together, however, the available evidence supports beneficial effects of physical activity in promoting bone development (Bailey et al., 1996; Modlesky and Lewis, 2002).

that most people will lose in their entire adult lives (Arlot et al., 1997). The increase in mineral contributes to increased bone strength. Mineral is accrued on the periosteal surface of bone, such that the bone grows wider. Increased bone width, independent of the increased mineral mass, also contributes to greater bone strength. Indeed, an increase of as little as 1 mm in the outer surface of bone increases strength substantially. Adding bone to the endosteal surface also increases strength (Parfitt, 1994; Wang et al., 2009). Increases in testosterone may be a greater stimulus of periosteal expansion than estrogen since testosterone contributes to wider and stronger bones in males compared with females. Retrospective studies in tennis players and gymnasts suggest structural adaptations may persist many years later in adulthood and are greatest when “impact” activity is initiated in childhood (Kannus et al., 1995; Bass et al., 1998). RCTs on this issue are few, although the available data are promising (McKay et al., 2000; Fuchs et al., 2001; MacKelvie et al., 2001, 2003; Lindén et al., 2006). Thus, impact exercise begun in childhood may result in lasting structural changes that may contribute to increased bone strength and decreased fracture risk later in life (Turner and Robling, 2003; Ferrari et al., 2006).

Adipose tissue The adipose “organ” is composed of fat cells known as adipocytes (Ailhaud and Hauner, 1998). Adipocytes are distributed throughout the body in various organs and tissues, although they are largely clustered anatomically in structures called fat depots, which include a large number of adipocytes held together by a scaffold-like structure of collagen and other structural molecules. In the traditional view of the adipocyte, the cell provides a storage structure for fatty acids in the form of triacylglycerol molecules, with fatty acids being released when metabolic fuel is needed (Arner and Eckel, 1998). While adipocytes play this critical role, they are also involved in a number of endocrine, autocrine, and paracrine actions and play a key role in regulating other tissues and biological functions, for example, immunity and blood pressure, energy balance, glucose and lipid metabolism, and energy demands of exercise (Ailhaud and Hauner, 1998; Frühbeck et al., 2001). The role of adipocytes in regulation of energy balance and in carbohydrate and lipid metabolism and the potential effects of physical activity on adipocyte function are of particular interest here, given growing concerns related to pediatric and adult obesity (Ogden et al., 2012) and the associated risk of cardiometabolic disease (Weiss et al., 2004; Eisenmann, 2007a,b; Steele et al., 2008). Metabolic differences among various fat depots are now well known (Frühbeck et al., 2001), and there is significant interest in the distribution of adipose tissue, the changes that occur during childhood and adolescence, and their clinical significance.

Adipocytes increase in size (hypertrophy) and number (hyperplasia) from birth through childhood and adolescence and into young adulthood

to accommodate energy storage needs. The number of adipocytes has been estimated to increase from about 5 billion at birth to 30 billion to 50 billion in the nonobese adult, with an increase in average diameter from about 30-40 μm at birth to about 80-100 μm in the young adult (Knittle et al., 1979; Bonnet and Rocour-Brumioul, 1981; Chumlea et al., 1982). In total the adipose organ contains about 0.5 kg of adipocytes at birth in both males and females, increasing to approximately 10 kg in average-weight-for-height males and 14 kg in females (Malina et al., 2004). There is wide interindividual variation, however, and the difficulty of investigating changes in the number and size of adipocytes is obvious given the invasiveness of the required biopsy procedures; understandably, then, data on these topics are scarce in children and adolescents. Also, since only subcutaneous depots are accessible, results must be extrapolated from a few sites.

Based on such information, the average size of adipocytes has been reported to increase two- to threefold in the first year of life, with little increase in nonobese boys and girls until puberty (Malina et al., 2004). A small increase in average adipocyte size at puberty is more obvious in girls than in boys. There is considerable variation in size across various subcutaneous sites and between subcutaneous and internal depots. The number of adipocytes is difficult to estimate. Available data suggest that the cellularity of adipose tissue does not increase significantly in early postnatal life (Malina et al., 2004). Thus, gain in fat mass is the result of an increase in the size of existing adipocytes. From about 1-2 years of age and continuing through early and middle childhood, the number of adipocytes increases gradually two- to threefold. With puberty the number practically doubles, followed by a plateau in late adolescence and early adulthood. The number of adipocytes is similar in boys and girls until puberty, when girls experience a greater increase than boys.

The increases in the number of adipocytes during infancy and puberty are considered critical for enlargement of the adipose tissue organ and for the risk of obesity. Since size and number are linked, the number of adipocytes can potentially increase at any age if fat storage mechanisms are stimulated by chronic energy surfeit (Hager, 1981; Chumlea et al., 1982). Energy expenditure through regular physical activity is a critical element in preventing energy surfeit and excess adiposity. While cellularity undoubtedly is strongly genetically determined, regular physical activity, through its contribution to energy expenditure, can contribute to less adipocyte hyperplasia by limiting hypertrophy.

Fat distribution Fat distribution refers to the location of fat depots on the body. The metabolic activities of fat depots differ, and small variation can have a long-term impact on fat distribution. Differences in metabolic properties across depots also have clinical implications. Visceral adipose tissue

in the abdominal cavity is more metabolically active (reflected by free fatty acid flux) than adipose tissue in other areas (Arner and Eckel, 1998), and higher amounts of visceral adipose tissue are associated with greater risk of metabolic complications, such as type 2 diabetes and cardiovascular disease (Daniels et al., 1999; He et al., 2007; Dencker et al., 2012). In contrast, subcutaneous fat, particularly in the gluteofemoral region, is generally associated with a lower risk of cardiometabolic disease. Age- and sex-associated variations in fat distribution contribute to age- and sex-associated differences in cardiometabolic disease prevalence. Girls have more subcutaneous fat than boys at all ages, although relative fat distribution is similar. After a rapid rise in subcutaneous fat in the first few months of life, both sexes experience a reduction through age 6 or 7 (Malina and Roche, 1983; Malina and Bouchard, 1988; Malina, 1996). Girls then show a linear increase in subcutaneous fat, whereas boys show a small increase between ages 7 and 12 or 13 and then an overall reduction during puberty. The thickness of subcutaneous fat on the trunk is approximately one-half that of subcutaneous fat on the extremities in both boys and girls during childhood. The ratio increases with age in males during adolescence but changes only slightly in girls. In males the increasing ratio of trunk to extremity subcutaneous fat is a consequence of slowly increasing trunk subcutaneous fat and a decrease in subcutaneous fat on the extremities. In girls, trunk and extremity subcutaneous fat increase at a similar rate; thus the ratio is stable (Malina and Bouchard, 1988). As a consequence, the sex difference in the distribution of body fat develops during adolescence. It is important to note that changes in subcutaneous fat pattern do not necessarily represent changes in abdominal visceral adipose tissue.

Tracking of subcutaneous fat has been investigated based on skinfold thicknesses and radiographs of fat widths in males and females across a broad age range (Katzmarzyk et al., 1999; Campbell et al., 2012). Results indicate that subcutaneous fat is labile during early childhood. After age 7 to 8, correlations between subcutaneous fat in later childhood and adolescence and adult subcutaneous fat are significant and moderate. Longitudinal data on tracking of visceral adipose tissue are not available, but percent body fat does appear to track. Thus children and especially adolescents with higher levels of body fat have a higher risk of being overfat at subsequent examinations and in adulthood, although variation is considerable, with some individuals moving away from high fatness categories, while some lean children move into higher fatness categories.

well as the difficulty of measuring physical activity. Longitudinal studies indicate small differences in fatness between active and inactive boys and girls. Although some school-based studies of the effects of physical activity on body composition have reported changes in BMI or skinfolds in the desired direction (Gortmaker et al., 1999; McMurray et al., 2002), most have not shown significant effects. High levels of physical activity are most likely needed to modify skinfold thicknesses and percent body fat. In adults, visceral adipose tissue declines with weight loss with exercise. In contrast, in a study of obese children aged 7-11, a 4-month physical activity program resulted in minimal change in abdominal visceral adipose tissue but a significant loss in abdominal subcutaneous adipose tissue (Gutin and Owens, 1999). In adults, decreases in fatness with exercise are due to a reduction in fat cell size, not number (You et al., 2006); whether this is true in children is not certain but appears likely. Given that adipocyte hypertrophy may trigger adipocyte hyperplasia (Ballor et al., 1998), energy expenditure through regular physical activity may be important in preventing excess adipose tissue cellularity. Regular physical activity also affects adipose tissue metabolism so that trained individuals have an increased ability to mobilize and oxidize fat, which is associated with increased levels of lipolysis, an increased respiratory quotient, and a lower risk of obesity (Depres and Lamarche, 2000).

Cardiorespiratory System

ume and heart rate, liters per minute), despite a decline in heart rate during growth. Similarly, increase in lung size (proportional to growth in height) results in greater lung volume and ventilation despite an age-associated decline in breathing frequency. From about age 6 to adulthood, maximal voluntary ventilation approximately doubles (50-100 L/min) (Malina et al., 2004). The general pattern of increase as a function of height is similar in boys and girls. In both, lung function tends to lag behind the increase in height during the adolescent growth spurt. As a result, peak gains in lung function occur about 2 years earlier in girls than in boys.

Blood volume is highly related to body mass and heart size in children and adolescents, and it is also well correlated with maximal oxygen uptake during childhood and adolescence (Malina et al., 2004). Blood volume increases from birth through adolescence, following the general pattern for changes in body mass. Both red blood cells and hemoglobin have a central role in transport of oxygen to tissues. Hematocrit, the percentage of blood volume explained by blood cells, increases progressively throughout childhood and adolescence in boys, but only through childhood in girls. Hemoglobin content, which is related to maximal oxygen uptake, heart volume, and body mass, increases progressively with age into late adolescence. Males have greater hemoglobin concentrations than females, especially relative to blood volume, which has functional implications for oxygen transport during intense exercise.

Growth in maximal aerobic power is influenced by growth in body size, so controlling for changes in body size during growth is essential. Although absolute (liters per minute) aerobic power increases into adolescence relative to body weight, there is a slight decline in both boys and girls, suggesting that body weight increases at a faster rate than maximal oxygen consumption, particularly during and after the adolescent growth spurt (Malina et al., 2004). Changes in maximal oxygen consumption during growth tend to be related more closely to fat-free mass than to body mass. Nevertheless, sex differences in maximal oxygen consumption per unit fat-free mass persist, and maximal oxygen consumption per unit fat-free mass declines with age.

Improvements in cardiorespiratory function—involving structural and functional adaptations in the lungs, heart, blood, and vascular system, as well as the oxidative capacity of skeletal muscle—occur with regular vigorous- and moderate-intensity physical activity (Malina et al., 2004). Concern about the application of invasive techniques limits the available data on adaptations in the oxygen transport system in children. Nevertheless, it is clear that aerobic capacity in youth increases with activity of sufficient intensity and that maximal stroke volume, blood volume, and oxidative enzymes improve after exercise training (Rowland, 1996). Training-induced changes in other components of the oxygen transport system remain to be determined.

Health- and Performance-Related Fitness

Physical fitness is a state of being that reflects a person’s ability to perform specific exercises or functions and is related to present and future health outcomes. Historically, efforts to assess the physical fitness of youth focused on measures designed to evaluate the ability to carry out certain physical tasks or activities, often related to athletic performance. In more recent years, the focus has shifted to greater emphasis on evaluating health-related fitness (IOM, 2012a) and assessing concurrent or future health status. Health- and performance-related fitness, while overlapping, are different constructs. Age- and sex-related changes in the components of both are strongly linked to the developmental changes in tissues and systems that occur during childhood and adolescence. Although genetic factors ultimately limit capacity, environmental and behavioral factors, including physical activity, interact with genes to determine the degree to which an individual’s full capacity is achieved.

Health-Related Fitness

Cardiorespiratory endurance, muscular strength and endurance, flexibility, and body composition are components of health-related fitness historically assessed in school-based fitness assessment programs (IOM, 2012a). These components of health-related fitness are considered important since they can be linked to the risk of cardiometabolic disease and musculoskeletal disability, chronic hypokinetic-related diseases.

Cardiorespiratory endurance Cardiorespiratory (aerobic) endurance reflects the functioning of the pulmonary and cardiovascular systems to deliver oxygen and the ability of tissues (primarily skeletal muscle) to extract oxygen from the blood. Defined clinically as the maximum oxygen consumption during a maximal graded exercise test, in practice it is usually measured indirectly as performance on a field test of endurance, such as 1- or 2-mile run time (IOM, 2012a). During childhood, aerobic capacity approximately doubles in both boys and girls, although girls on average possess a lower capacity. Males continue to improve during adolescence, up to ages 17-18, while aerobic capacity plateaus around age 14 in females (Malina et al., 2004), resulting in an approximately 20 percent difference between males and females (Rowland, 2005).

2005; Pate et al., 2006), coincident with increased sedentariness and obesity and a greater prevalence of metabolic syndrome in youth. Aerobic exercise has been shown to increase cardiorespiratory endurance by about 5-15 percent in youth (Malina et al., 2004; HHS, 2008). The programs that produce this benefit involve continuous vigorous- or moderate-intensity aerobic activity of various types for 30-45 minutes per session at least 3 days per week over a period of at least 1-3 months (Baquet et al., 2002); improvements are greater with more frequent exercise (Baquet et al., 2003).

Muscle strength and endurance Muscle strength is defined as the highest force generated during a single maximum voluntary contraction, whereas muscle endurance is the ability to perform repeated muscular contraction and force development over a period of time. Muscle strength and endurance are correlated, especially at higher levels of force production. Muscle strength is proportional to the cross-sectional area of skeletal muscle; consequently, strength growth curves parallel growth curves for body weight and skeletal muscle mass (Malina et al., 2004).

Both males and females show impressive increases in muscle strength from childhood to adolescence. Strength in children increases linearly, with boys having a slight advantage over girls. However, these sex differences are magnified during the adolescent years as a result of maturation (Malina and Roche, 1983). Differences in muscle strength between boys and girls become more apparent after puberty, primarily as a result of the production of sex steroid hormones. In boys the increase in strength during adolescence lags behind the growth spurt by at least a year (peak height velocity), which may explain why some boys experience a brief period of clumsiness or awkwardness during puberty, as they have not yet acquired the muscle strength necessary to handle the changes associated with their larger bodies. Muscle strength increases at its greatest rate approximately 1 year after peak height velocity in boys, whereas for girls the strength spurt generally occurs during the same year as peak height velocity (Bar-Or, 1983).

A compelling body of evidence indicates that with resistance training children and adolescents can significantly increase their strength above that expected as a result of normal growth and maturation, provided that the training program is of sufficient intensity, volume, and duration (Committee on Sports Medicine Fitness, 2001). Both boys and girls can benefit, and strength gains in children as young as 5-6 have been reported (Faigenbaum et al., 2009), although most studies are of older children and adolescents. Gains in muscle strength of about 30 percent are typical, although considerably larger gains have been reported. Adolescents make greater gains than preadolescents in absolute strength, whereas reported relative (percent above initial strength) gains in strength during preadolescence and adolescence are similar. A variety of programs and modalities have proved

efficacious (Council on Sports Medicine Fitness, 2008), as long as load (~10-15 repetitions maximum) and duration (~8-20 weeks) are adequate. As in adults, training adaptations in youth are specific to the muscle action or muscle groups that are trained, and gains are transient if training is not maintained (Faigenbaum et al., 2009).

Youth resistance training, as with most physical activities, does carry some degree of risk of musculoskeletal injury, yet the risk is no greater than that associated with other sports and activities in which children and adolescents participate (Council on Sports Medicine Fitness, 2008; Faigenbaum et al., 2009) as long as age-appropriate training guidelines are followed. A traditional area of concern has been the potential for training-induced damage to growth cartilage, which could result in growth disturbances. However, a recent review found no reports of injury to growth cartilage in any prospective study of resistance training in youth and no evidence to suggest that resistance training negatively impacts growth and maturation during childhood and adolescence (Faigenbaum et al., 2009). Injuries typically occur in unsupervised settings and when inappropriate loads and progressions are imposed.

In addition to the obvious goal of gaining strength, resistance training may be undertaken to improve sports performance and prevent injuries, rehabilitate injuries, and enhance health. Appropriately supervised programs emphasizing strengthening of trunk muscles in children theoretically benefit sport-specific skill acquisition and postural control, although these benefits are difficult to study and thus are supported by little empirical evidence (Council on Sports Medicine Fitness, 2008). Similarly, results are inconsistent regarding the translation of increased strength to enhanced athletic performance in youth. Limited evidence suggests that strength-training programs that address common overuse injuries may help reduce injuries in adolescents, but whether the same is true in preadolescents is unclear (Council on Sports Medicine Fitness, 2008). Increasing evidence suggests that strength training, like other forms of physical activity, has a beneficial effect on measurable health indices in youth, such as cardiovascular fitness, body composition, blood lipid profiles and insulin sensitivity (Faigenbaum, 2007; Benson et al., 2008), bone mineral density and bone geometry (Morris et al., 1997; MacKelvie et al., 2004), and mental health (Holloway et al., 1988; Faigenbaum et al., 1997; Annesi et al., 2005; Faigenbaum, 2007). Some work has shown that muscle fitness, reflected in a composite index combining measures of muscle strength and endurance, and cardiorespiratory fitness are independently and negatively associated with clustered metabolic risk (Steene-Johannessen et al., 2009). Moreover, children with low muscle strength may be at increased risk of fracture with exercise (Clark et al., 2011). Finally, muscle hypertrophy, which adds to fat-free mass, contributes to resting metabolic rate and therefore total daily

energy expenditure. Resistance training may be particularly useful for raising metabolic rate in overweight and obese children without the risk associated with higher-impact activities (Watts et al., 2005; Benson et al., 2007).

Flexibility Flexibility has been operationally defined as “the intrinsic property of body tissues, including muscle and connective tissues, that determines the range of motion achievable without injury at a joint or group of joints” (IOM, 2012b, p. 190). At all ages, girls demonstrate greater flexibility than boys, and the difference is greatest during the adolescent growth spurt and sexual maturation. Perhaps the most common field measure of flexibility in children and youth is the sit-and-reach test (IOM, 2012b) of low-back flexibility. Low-back flexibility as measured by this test is stable in girls from age 5 to 11 and increases until late adolescence. In boys, low-back flexibility declines linearly starting at age 5, reaching its nadir at about age 12, and then increases into late adolescence. The unique pattern of age- and sex-associated variation is related to the growth of the lower extremities and the trunk during adolescence. In boys the nadir in low-back flexibility coincides with the adolescent growth spurt in leg length. In both boys and girls, the increase during adolescence coincides with the growth spurt in trunk length and arm length, which influences reach. Flexibility in both males and females tends to decline after age 17, in part as a result of a decline in physical activity and normal aging.

The principal health outcomes hypothesized to be associated with flexibility are prevention of and relief from low-back pain, prevention of musculoskeletal injury, and improved posture. These associations have been studied in adults, with equivocal results (Plowman, 1992). Although flexibility has long been included in national youth fitness tests, it has proven difficult to establish a link between flexibility and health (IOM, 2012a). In contrast to other fitness components that are general or systemic in nature, flexibility is highly specific to each joint of the body. Although appropriate stretching may increase flexibility, establishing a link to improved functional capacity and fitness is difficult. A few studies suggest that improvements in flexibility as measured by the sit-and-reach test may be related to less low-back pain (Jones et al., 2007; Ahlqwist et al., 2008), but the evidence is weak. Consequently, the Institute of Medicine (IOM) Committee on Fitness Measures and Health Outcomes in its recent report elected to forego recommending a flexibility test for a national youth fitness test battery pending further research to confirm the relationship between flexibility and health and to develop national normative data (IOM, 2012a).

Body composition Body composition is the component of health-related fitness that relates to the relative amount of adipose tissue, muscle, bone, and other vital components (e.g., organs, connective tissues, fluid compart-

ments) that make up body weight. Most feasible methods for assessing body composition are based on models that divide the body into fat and fat-free (all nonfat constituents) components (Going et al., 2012). Although fat mass and adipose tissue are not equivalent components, fat mass is easier to estimate than adipose tissue, and it is correlated with performance and disease risk. In settings in which estimation of body fat is difficult, weight-for-height ratios often are used as surrogates for body composition. Indeed, definitions of pediatric overweight and obesity have been based on BMI, calculated as weight in kilograms divided by height squared. Child and adolescent obesity defined by BMI remains at all-time highs. Population surveys indicate that approximately 33 percent of all boys and girls are overweight, and nearly one in five are obese (Ogden and Flegal, 2011). The tendency for excess fatness to persist from childhood and adolescence into adulthood (Daniels et al., 2005), coupled with the strong association between obesity and chronic disease (Weiss and Caprio, 2005; Barlow, 2007), has caused great concern for future obesity levels and the health of youth and adults alike (IOM, 2005, 2012b).

The increase in prevalence of obesity is undoubtedly due to a mismatch between energy intake and expenditure. Population surveys have shown that few children and youth meet recommended levels of daily physical activity (see Chapter 2 ). Prospective studies have shown a significant and inverse relationship between habitual physical activity and weight gain (Berkey et al., 2003), and in some studies physical activity is a better predictor of weight gain than estimates of calorie or fat intake (Berkey et al., 2000; Janssen et al., 2005). These relationships are better established in adults than in children and youth, although even in preschool children, low levels of physical activity, estimated from doubly labeled water, were found to be indicative of higher body fat content (Davies et al., 1995). While studies of exercise without caloric restriction generally show only small effects on body weight, significant albeit moderate reductions of body fat are generally reported (Eisenmann, 2003). Moreover, even in the absence of significant weight loss, exercise has beneficial effects on risk factors for cardiometabolic disease (Ross and Bradshaw, 2009; Gutin and Owens, 2011).

Body mass index Changes in weight for height with growth and maturation for U.S. boys and girls are described in CDC growth curves (Kuczmarski et al., 2000). Current growth curves were derived from U.S. population surveys conducted before the increase in weight for height that defines today’s pediatric obesity epidemic. In boys and girls, BMI declines during early childhood, reaching its nadir at about ages 5-6, and then increases through adolescence. A gender difference emerges during puberty, with males gaining greater fat-free mass than females. Both the

period of “adiposity rebound” (the increase in BMI in midchildhood following the decline in early childhood) and puberty are times of risk for excess fat gain that correlates with future adiposity (Rolland-Cachera et al., 1984). Physical activity and BMI are inversely correlated in children and adolescents, although the correlations are modest (Lohman et al., 2006), reflecting the difficulty of measuring physical activity, as well as variation in body composition and physical activity at a given weight (Rowlands et al., 2000). Indeed, when studied separately, fat mass index (FMI, or fat mass divided by height squared) and fat-free mass index (FFMI, or fat-free mass divided by height squared) are both inversely related to physical activity. With FMI controlled, however, FFMI is positively related to physical activity, indicating that, for a given level of body fat, individuals with more fat-free mass are more active (Lohman et al., 2006). BMI cut-points for defining overweight and obesity have historically been based on age- and gender-specific population distributions of BMI. Recent work has shown good correspondence between BMI standards and percent fat standards that are referenced to health criteria (Laurson et al., 2011). These new standards should prove useful for identifying children and adolescents at risk for higher levels of cardiometabolic risk factors.

Percent body fat Direct measures of body fat as a percent of weight provide a better index of adiposity and health risk than BMI (Zeng et al., 2012), which is confounded by variation in lean tissue mass relative to height. Recently, percent fat growth curves were established for representative samples of U.S. boys and girls using National Health and Nutrition Examination Survey (NHANES) data (Laurson et al., 2011; Ogden and Flegal, 2011). Median percent fat for boys aged 5-18 ranged from 14 to 19 percent and for girls across the same ages 15 to 28 percent. In both boys and girls, percent fat increases slowly during early childhood, with girls having a consistently greater relative fatness than boys after ages 5-6. In girls, percent fat increases gradually throughout adolescence in the same manner as fat mass. In boys, percent fat increases gradually until the adolescent growth spurt and thereafter gradually declines until about age 16-17, reflecting the rapid growth in fat-free mass relative to fat mass. After age 17, percent fat in males gradually increases again into adulthood.

The increased prevalence of child and adolescent obesity as defined by BMI presumably also reflects increased adiposity, although the degree is not certain as population-based estimates of percent fat have only recently been developed (Laurson et al., 2011). Health-related percent fat standards recently were developed by determining levels of body fat associated with greater occurrence of chronic disease risk factors defined by metabolic syndrome (Going et al., 2011). In boys and girls aged 12-18, body fat above

20-24 percent and above 27-31 percent, respectively, was predictive of metabolic syndrome.

Physical activity is inversely correlated with percent body fat (Rowlands et al., 2000; Lohman et al., 2006), although the correlations are modest, and changes in overall fatness as well as subcutaneous adipose tissue with habitual physical activity are reasonably well documented in children and adolescents (Gutin and Humphries, 1998; Gutin and Owens, 1999; Dionne et al., 2000). In youth, as in adults, the effects of exercise without caloric restriction are modest and are influenced by the initial level of body fat and the duration and regimen of exercise (Going, 1999). Experimental studies have documented reductions in percent body fat with aerobic exercise, especially in children and adolescents who are overweight or obese at the initiation of an exercise program (Davis et al., 2012). Regular physical activity also affects adipose tissue metabolism (Gutin and Owens, 1999). Individuals who engage in aerobic endurance exercise training have an increased ability to mobilize and oxidize fat, which is associated with increased levels of lipolysis (Depres and Lamarche, 2000). Similar information on adipose tissue metabolism in children and youth is lacking, although one can reasonably expect similar adaptations in older adolescents.

Metabolic syndrome The tendency for risk factors for cardiometabolic disease to cluster, now called metabolic syndrome, is well recognized in adults (Alberti and Zimmet, 1998). Similar clustering occurs in older children and especially adolescents (Cook et al., 2003), and interest in metabolic syndrome has increased, driven by the increased prevalence of pediatric obesity and the increasing incidence and earlier onset of type 2 diabetes in youth. There is as yet no accepted definition of metabolic syndrome for use in pediatric populations (Jolliffe and Janssen, 2007). Typically, adult definitions are extrapolated to children and adolescents, with appropriate adjustments of the thresholds for the defining variables. Perhaps the most common approach is to emulate the National Cholesterol Education Program (NCEP), which defines metabolic syndrome as exceeding thresholds on three of five components: waist circumference, blood pressure (systolic or diastolic), blood lipids (high-density lipoprotein [HDL] and triglycerides), and blood glucose levels (NIH, 2001).

loss of 5-10 percent of body weight through calorie restriction and exercise has been shown to reduce the risk of cardiometabolic disease by improving risk factors (Diabetes Prevention Program Research Group, 2002; Ross and Janiszewski, 2008). In particular, weight loss results in reduced visceral adipose tissue, a strong correlate of risk (Knowler et al., 2002), as well as lower blood pressure and blood glucose levels due to improved insulin sensitivity. Even without significant weight loss, exercise can have significant effects in adults by improving glucose metabolism, improving lipid and lipoprotein profiles, and lowering blood pressure, particularly for those who are significantly overweight (Ross and Bradshaw, 2009). Similar benefits have been observed in adolescents.

A growing body of literature addresses the associations of physical activity, physical fitness, and body fatness with the risk of metabolic syndrome and its components in children and especially adolescents (Platat et al., 2006; McMurray et al., 2008; Rubin et al., 2008; Thomas and Williams, 2008; Christodoulos et al., 2012). Studies in adults have shown that higher levels of physical activity predict slower progression toward metabolic syndrome in apparently healthy men and women (Laaksonen et al., 2002; Ekelund et al., 2005), an association that is independent of changes in body fatness and cardiorespiratory fitness (Ekelund et al., 2007). Few population studies have focused on these relationships in children and adolescents, and the use of self-reported activity, which is imprecise in these populations, tends to obscure associations. In a large sample of U.S. adolescents aged 12-19 in the 1999-2002 NHANES, for example, there was a trend for metabolic syndrome to be more common in adolescents with low activity levels than in those with moderate or high activity levels, although the differences among groups were not statistically significant (Pan and Pratt, 2008). Moreover, for each component of metabolic syndrome, prevalence was generally lower with higher physical activity levels, and adolescents with low physical activity levels had the highest rates of all metabolic syndrome components.

The association between cardiorespiratory fitness and metabolic syndrome also was examined in the 1999-2002 NHANES (Lobelo et al., 2010). Cardiorespiratory fitness was measured as estimated peak oxygen consumption using a submaximal treadmill exercise protocol, and metabolic syndrome was represented as a “clustered score” derived from five established risk factors for cardiovascular disease, an adiposity index, insulin resistance, systolic blood pressure, triglycerides, and the ratio of total to HDL cholesterol. Mean clustered risk score decreased across increasing fifths (quintiles) of cardiorespiratory fitness in both males and females. The most significant decline in risk score was observed from the first (lowest) to the second quintile (53.6 percent and 37.5 percent in males and females, respectively), and the association remained significant in both overweight

and normal-weight males and in normal-weight females. Other studies, using the approach of cross-tabulating subjects into distinct fitness and fatness categories, have examined associations of fitness and fatness with metabolic syndrome risk (Eisenmann et al., 2005, 2007a,b; Dubose et al., 2007). Although different measures of fitness, fatness, and metabolic syndrome risk were used, the results taken together across a wide age range (7-18) show that fitness modifies the influence of fatness on metabolic syndrome risk. In both males and females, high-fit/low-fatness subjects have less metabolic syndrome risk than low-fit/high-fatness subjects (Eisenmann, 2007).

That many adult chronic health conditions have their origins in childhood and adolescence is well supported (Kannel and Dawber, 1972; Lauer et al., 1975; Berenson et al., 1998; IOM, 2004). Both biological (e.g., adiposity, lipids) and behavioral (e.g., physical activity) risk factors tend to track from childhood and especially adolescence into adulthood. Childhood BMI is related to adult BMI and adiposity (Guo et al., 1994, 2000; Freedman et al., 2005), and as many as 80 percent of obese adolescents become obese adults (Daniels et al., 2005). Coexistence of cardiometabolic risk factors, even at young ages (Dubose et al., 2007; Ramírez-Vélez et al., 2012), has been noted, and these components of metabolic syndrome also have been shown to track to adulthood (Bao et al., 1994; Katzmarzyk et al., 2001; Huang et al., 2008). Landmark studies from the Bogalusa Heart Study (Berenson et al., 1998; Li et al., 2003) and others (Mahoney et al., 1996; Davis et al., 2001; Morrison et al., 2007, 2008) have demonstrated that cardiometabolic risk factors present in childhood are predictive of adult disease.

interventions in overweight children and adolescents commonly combine exercise and dietary restriction, making it difficult to disentangle their independent effects. Nonetheless, diet and exercise have different effects on body composition: While both contribute to fat loss, only exercise increases muscle mass and thus has a direct effect on metabolic health. In children and youth, as in adults, the effect of exercise on cardiometabolic risk factors is greater in overweight/obese youth than in their normal-weight peers (Kang et al., 2002; Lazaar et al., 2007).

Exercise also may have important benefits even without significant modification of body composition (Bell et al., 2007). Experimental studies in overweight and obese youth have shown that exercise leads to reductions in visceral fat (Owens et al., 1999; Gutin et al., 2002; Lee at al., 2005; Barbeau et al., 2007; Kim and Lee, 2009) without a significant change in BMI, as well as improvement in markers of metabolic syndrome, primarily fasting insulin and insulin resistance (Treuth et al., 1998; Ferguson et al., 1999; Carrel et al., 2005; Nassis et al., 2005; Meyer et al., 2006; Shaibi et al., 2006; Bell et al., 2007). Results from experimental studies of the effects of exercise on lipids and lipoproteins (Stoedefalke et al., 2000; Kelley and Kelley, 2008; Janssen and LeBlanc, 2010) are mixed. Although some studies have shown improved lipid and lipoprotein profiles, primarily a decrease in low-density lipoprotein (LDL) cholesterol and triglyceride concentrations and an increase in HDL cholesterol (Ferguson et al., 1999), other studies have shown no improvement in these outcomes (Kelley and Kelley, 2008). In part, such conflicting results are likely due to initial differences in body composition and severity of hyperlipidemia. Well-controlled exercise training studies in obese children (Escalante et al., 2012) and children with adverse blood lipid and lipoprotein profiles have shown positive alterations in their profiles (Stoedefalke et al., 2000), whereas results in normolipid-emic children and adolescents are equivocal. Similarly, exercise has little effect on resting blood pressure in normotensive children and adolescents (Kelley and Kelley, 2008), whereas reductions in resting systolic and sometimes diastolic pressures have been reported in youth with high blood pressure (Hagberg et al., 1983, 1984; Danforth et al., 1990; Ewart et al., 1998; Farpour-Lambert et al., 2009; Janssen and LeBlanc, 2010).

stronger in adolescents than in children. In one study of boys and girls aged 10-15, those who were obese and unfit had the highest levels of systemic inflammation, whereas those who were obese yet fit had levels as low as those who were lean and fit (Halle et al., 2004). In another study, low-grade inflammation was negatively associated with muscle strength in overweight adolescents after controlling for cardiorespiratory fitness, suggesting that high levels of muscle strength may counteract some of the negative consequences of higher levels of body fat (Ruiz et al., 2008). Experimental studies of the effects of exercise and markers of low-grade inflammation in children and adolescents are lacking. Improved cardiorespiratory fitness in adults (Church et al., 2002), however, has been shown to be inversely related to concentration of C-reactive protein (CRP), a marker of low-grade inflammation. In a small study of a lifestyle intervention entailing 45 minutes of physical activity 3 times per week for 3 months, a small reduction in body fat and an overall decrease in inflammatory factors (CRP, interleukin [IL]-6) were seen in obese adolescents (Balagopal et al., 2005).

Performance-Related Fitness

Speed, muscle power, agility, and balance (static and dynamic) are aspects of performance-related fitness that change during body development in predictable ways associated with the development of tissues and systems discussed above (Malina et al., 2004). Running speed and muscle power are related, and both depend on full development of the neuromuscular system. Running speed and muscle power are similar for boys and girls during childhood (Haubenstricker and Seefeldt, 1986). After puberty, largely because of differences in muscle mass and muscle strength, males continue to make significant annual gains, while females tend to plateau during the adolescent years. Sociocultural factors and increasing inactivity among girls relative to boys, along with changes in body proportion and a lowering of the center of gravity, may also contribute to gender differences (Malina et al., 2004).

Balance—the ability to maintain equilibrium—generally improves from ages 3 to 18 (Williams, 1983). Research suggests that females outperform males on tests of static and dynamic balance during childhood and that this advantage persists through puberty (Malina et al., 2004).

of training from changes expected with normal growth. Changes in body size, physique, and body composition associated with growth and maturation are important factors that affect strength and motor performance. The relationships vary among performance measures and with age, and these factors often are inadequately controlled in studies of components of performance-related fitness and performance tasks.

PSYCHOSOCIAL HEALTH

Research supports the positive impact of physical activity on the overall psychological health and social engagement of every student. A well-designed physical education curriculum provides students with social and emotional benefits (NASPE, 2001). Simultaneously, exposure to failure experiences, emphasis on competitive sports, and elitism for naturally inclined athletes, along with bullying and teasing of unfit, uncoordinated, and overweight youth, may be important factors discouraging participation in current and future physical activity (Kohl and Hobbs, 1998; Sallis et al., 2000; Allender et al., 2006). School-based physical activity, including physical education and sports, is designed to increase physical activity while also improving motor skills and development, self-efficacy, and general feelings of competency and engaging children socially (Bailey, 2006). The hoped-for psychosocial outcomes of physical education and other physical activity programs in the school setting have been found to be critical for continued physical activity across the life span and are themselves powerful long-term determinants of physical activity (Bauman et al., 2012). Unfortunately, significant gaps exist between the intent and reality of school-based physical education and other activity programs (HHS, 2013).

A large number of psychological and social outcomes have been examined. Specific aspects of psychosocial health showing a beneficial relationship to physical activity include, among others, self-efficacy, self-concept, self-worth (Haugen et al., 2011), social behaviors (Cradock et al., 2009), pro-school attitudes, motivation and goal orientation (Digelidis et al., 2003), relatedness, friendships (de la Haye et al., 2011; Macdonald-Wallis et al., 2011), task orientation, team building, bullying, and racial prejudice (Byrd and Ross, 1991). Most studies are descriptive, finding bidirectional associations between psychosocial outcomes and physical activity. Reviews and meta-analyses confirm a positive association between physical activity and self-esteem, especially for aerobic activities (McAuley, 1994).

Among psychosocial factors, self-efficacy (confidence in one’s ability to be physically active in specific situations) has emerged as an important correlate of physical activity from a large body of work based on the durable and practically useful social learning theory (Bandura and McClelland, 1977; Bandura, 1995). Bandura’s theory compels consideration of the

psychosocial and physical environments, the individual, and in this case the behavior of physical activity. Using this framework, physical activity itself has been shown to be a consistent positive correlate as well as a determinant of physical activity in children and adolescents. A large amount of reviewed research has found that physical education and physical activity experiences can increase children’s confidence in being active and lead to continued participation in physical activity (Bauman et al., 2012). RCTs have shown that both self-efficacy and social interactions leading to perceived social support influence changes in physical activity (Dishman et al., 2009). Skill mastery, confidence building, and group support are well-known strategies for advancing student learning and well-being in many educational domains in the school setting and apply equally to school physical education and other physical activity. Early observational studies of physical, social, and environmental determinants of physical activity at home, school, and recess indicated that prompts to be active (or not) from peers and adults accounted for a significant amount of the variance in directly observed physical activity (Elder et al., 1998). One longitudinal study following the variability and tracking of physical activity in young children showed that most of the variability in both home and recess activity was accounted for by short-term social and physical environmental factors, such as prompts from others and being outdoors (Sallis et al., 1995). Another study, examining activity among preschool children, found that, contrary to common belief, most of the time spent in preschool was sedentary, and correlates of activity were different for preschool boys and girls (Byun et al., 2011). In addition, significant variation in activity by preschool site was noted, indicating that local environmental conditions, including physical environment and equipment, policies, and teacher and administrative quality characteristics, play an important role in promoting physical activity (Brown et al., 2009).

Studies in middle and high school populations have strengthened the evidence base on relationships among self-efficacy, physical activity, and social support (from adults and peers). This research has highlighted the central contribution of self-efficacy and social support in protecting against a decline in activity levels among adolescent girls (Dishman et al., 2009, 2010). Evidence indicates further that these impacts spread to activities outside the school setting (Lytle et al., 2009). Findings of a related study suggest that leisure-time physical activity among middle school students was linked to motivation-related experiences in physical education (Cox et al., 2008).

sistently found to be more active than girls from ages 4 to 9. For other age groups of children and adolescents, sex is correlated with but not a determinant of activity (Bauman et al., 2012). These findings suggest the need to tailor physical education and physical activity programs for youth specifically to increase self-efficacy and enjoyment of physical activity among girls (Dishman et al., 2005; Barr-Anderson et al., 2008; Butt et al., 2011).

In summary, a broad range of beneficial psychosocial health outcomes have been associated with physical activity. The promotion of more physical activity and quality physical education in the school setting is likely to result in psychosocially healthier children who are more likely to engage in physical activity as adults. Schools can play an important role in ensuring opportunities for physical activity for a segment of the youth population that otherwise may not have the resources to engage in such activity. It makes sense to assume that, if physical activity experiences and environments were once again structured into the daily school environment of children and adolescents, individuals’ feelings of self-efficacy regarding physical activity would increase in the U.S. population.

MENTAL HEALTH

Mental illness is a serious public health issue. It has been estimated that by 2010 mental illness will account for 15 percent of the global burden of disease (Biddle and Mutrie, 2008; Biddle and Asare, 2011). Young people are disproportionately affected by depression, anxiety, and other mental health disorders (Viner and Booy, 2005; Biddle and Asare, 2011). Approximately 20 percent of school-age children have a diagnosable mental health disorder (U.S. Public Health Service, 2000), and overweight children are at particular risk (Ahn and Fedewa, 2011). Mental health naturally affects academic performance on many levels (Charvat, 2012). Students suffering from depression, anxiety, mood disorders, and emotional disturbances perform more poorly in school, exhibit more behavioral and disciplinary problems, and have poorer attendance relative to mentally healthy children. Thus it is in schools’ interest to take measures to support mental health among the student population. In addition to other benefits, providing adequate amounts of physical activity in a way that is inviting and safe for children of all ability levels is one simple way in which schools can contribute to students’ mental health.

Impact of Physical Activity on Mental Health

Strong et al., 2005; Hallal et al., 2006; Ahn and Fedewa, 2011; Biddle and Asare, 2011). Numerous observational studies have established the association between physical activity and mental health but are inadequate to clarify the direction of that association (Strong et al., 2005). It may be that physical activity improves mental health, or it may be that people are more physically active when they are mentally healthy. Most likely the relationship is bidirectional.

Several longitudinal and intervention studies have clarified that physical activity positively impacts mental health (Penedo and Dahn, 2005; Strong et al., 2005). Physical activity has most often been shown to reduce symptoms of depression and anxiety and improve mood (Penedo and Dahn, 2005; Dishman et al., 2006; Biddle and Asare, 2011). In addition to reducing symptoms of depression and anxiety, studies indicate that regular physical activity may help prevent the onset of these conditions (Penedo and Dahn, 2005). Reductions in depression and anxiety are the commonly measured outcomes (Strong et al., 2005; Ahn and Fedewa, 2011). However, reductions in states of confusion, anger, tension, stress, anxiety sensitivity (a precursor to panic attacks and panic disorders), posttraumatic stress disorder/psychological distress, emotional disturbance, and negative affect have been observed, as well as increases in positive expectations; fewer emotional barriers; general well-being; satisfaction with personal appearance; and improved life satisfaction, self-worth, and quality of life (Heller et al., 2004; Peluso and Guerra de Andrade, 2005; Penedo and Dahn, 2005; Dishman et al., 2006; Hallal et al., 2006; Ahn and Fedewa, 2011; Biddle and Asare, 2011). Among adolescents and young adult females, exercise has been found to be more effective than cognitive-behavioral therapy in reducing the pursuit of thinness and the frequency of bingeing, purging, and laxative abuse (Sundgot-Borgen et al., 2002; Hallal et al., 2006). The favorable effects of physical activity on sleep may also contribute to mental health (Dishman et al., 2006).

The impact of physical activity on these measures of mental health is moderate, with effect sizes generally ranging from 0.4 to 0.7 (Biddle and Asare, 2011). In one meta-analysis of intervention trials, the RCTs had an effect size of 0.3, whereas other trials had an effect size of 0.57.

Ideal Type, Length, and Duration of Physical Activity

Intervention trials that examine the relationship between physical activity and mental health often fail to specify the exact nature of the intervention, making it difficult to determine the ideal frequency, intensity, duration, and type of physical activity involved (Penedo and Dahn, 2005; Ahn and Fedewa, 2011; Biddle and Asare, 2011).

Many different types of physical activity—including aerobic activity, resistance training, yoga, dance, flexibility training, walking programs, and body building—have been shown to improve mood and other mental health indicators. The evidence is strongest for aerobic physical activity, particularly for reduction of anxiety symptoms and stress (Peluso and Guerra de Andrade, 2005; Dishman et al., 2006; Martikainen et al., 2013), because more of these studies have been conducted (Peluso and Guerra de Andrade, 2005). One meta-analysis of RCTs concluded that physical activity interventions focused exclusively on circuit training had the greatest effect on mental health indicators, followed closely by interventions that included various types of physical activity (Ahn and Fedewa, 2011). Among studies other than RCTs, only participation in sports had a significant impact on mental health (Ahn and Fedewa, 2011). The few studies that investigated the impact of vigorous- versus lower-intensity physical activity (Larun et al., 2006; Biddle and Asare, 2011) found no difference, suggesting that perhaps all levels of physical activity may be helpful. Among adults, studies have consistently shown beneficial effects of both aerobic exercise and resistance training. Ahn and Fedewa (2011) concluded that both moderate and intense physical activity have a significant impact on mental health, although when just RCTs were considered, only intense physical activity was significant (Ahn and Fedewa, 2011). While physical activity carries few risks for mental health, it is important to note that excessive physical activity or specialization too early in certain types of competitive physical activity has been associated with negative mental health outcomes and therefore should be avoided (Peluso and Guerra de Andrade, 2005; Hallal et al., 2006). Furthermore, to reach all children, including those that may be at highest risk for inactivity, obesity, and mental health problems, physical activity programming needs to be nonthreatening and geared toward creating a positive experience for children of all skill and fitness levels (Amis et al., 2012).

Various types of physical activity programming have been shown to have a positive influence on mental health outcomes. Higher levels of attendance and participation in physical education are inversely associated with feelings of sadness and risk of considering suicide (Brosnahan et al., 2004). Classroom physical activity is associated with reduced use of medication for attention deficit hyperactivity disorder (Katz et al., 2010). And participation in recess is associated with better student classroom behavior, better focus, and less fidgeting (Pellegrini et al., 1995; Jarrett et al., 1998; Barros et al., 2009).

length and duration of physical activity for improving mental health remain unclear, however. Regular exercise is associated with improved mood, but results are inconsistent for the association between mood and medium- or long-term exercise (Dua and Hargreaves, 1992; Slaven and Lee, 1997; Dimeo et al., 2001; Dunn et al., 2001; Kritz-Silverstein et al., 2001; Sexton et al., 2001; Leppamaki et al., 2002; Peluso and Guerra de Andrade, 2005). Studies often do not specify the frequency and duration of physical activity episodes; among those that do, interventions ranged from 6 weeks to 2 years in duration. In their meta-analysis, Ahn and Fedewa (2011) found that, comparing interventions entailing a total of more than 33 hours, 20-33 hours, and less than 20 hours, the longer programs were more effective. Overall, the lack of reporting and the variable length and duration of reported interventions make it difficult to draw conclusions regarding dose (Ahn and Fedewa, 2011).

In addition to more structured opportunities, naturally occurring physical activity outside of school time is associated with fewer depressive symptoms among adolescents (Penedo and Dahn, 2005). RCTs have demonstrated that physical activity involving entire classrooms of students is effective in alleviating negative mental health outcomes (Ahn and Fedewa, 2011). Non-RCT studies have shown individualized approaches to be most effective and small-group approaches to be effective to a more limited extent (Ahn and Fedewa, 2011). Interventions have been shown to be effective in improving mental health when delivered by classroom teachers, physical education specialists, or researchers but may be most effective when conducted with a physical education specialist (Ahn and Fedewa, 2011). Many physical activity interventions include elements of social interaction and support; however, studies to date have been unable to distinguish whether the physical activity itself or these other factors account for the observed effects on mental health (Hasselstrom et al., 2002; Hallal et al., 2006). Finally, a few trials (Larun et al., 2006; Biddle and Asare, 2011) have compared the effects of physical activity and psychosocial interventions, finding that physical activity may be equally effective but may not provide any added benefit.

Subgroup Effects

Although studies frequently fail to report the age of participants, data on the effects of physical activity on mental health are strongest for adults participating in high-intensity physical activity (Ahn and Fedewa, 2011). However, evidence relating physical activity to various measures of mental health has shown consistent, significant effects on individuals aged 11-20. A large prospective study found that physical activity was inversely associated with depression in early adolescence (Hasselstrom et al., 2002; Hallal

et al., 2006); fewer studies have been conducted among younger children. Correlation studies have shown that the association of physical activity with depression is not affected by age (Ahn and Fedewa, 2011).

Few studies have examined the influence of other sociodemographic characteristics of participants on the relationship between physical activity and mental health (Ahn and Fedewa, 2011), but studies have been conducted in populations with diverse characteristics. One study of low-income Hispanic children randomized to an aerobic intensity program found that the intervention group was less likely to present with depression but did not report reduced anxiety (Crews et al., 2004; Hallal et al., 2006). A study that included black and white children (aged 7-11) found that a 40-minute daily dose of aerobic exercise significantly reduced depressive symptoms and increased physical appearance self-worth in both black and white children and increased global self-worth in white children compared with controls (Petty et al., 2009). Physical activity also has been positively associated with mental health regardless of weight status (normal versus overweight) or gender (male versus female) (Petty et al., 2009; Ahn and Fedewa, 2011); however, results are stronger for males (Ahn and Fedewa, 2011).

Improvements in mental health as a result of physical activity may be more pronounced among clinically diagnosed populations, especially those with cognitive impairment or posttraumatic stress disorder (Craft and Landers, 1998; Ahn and Fedewa, 2011; Biddle and Asare, 2011). Evidence is less clear for youth with clinical depression (Craft and Landers, 1998; Larun et al., 2006; Biddle and Asare, 2011). Individuals diagnosed with major depression undergoing an intervention entailing aerobic exercise have shown significant improvement in depression and lower relapse rates, comparable to results seen in participants receiving psychotropic treatment (Babyak et al., 2000; Penedo and Dahn, 2005). One program for adults with Down syndrome providing three sessions of exercise and health education per week for 12 weeks resulted in more positive expectations, fewer emotional barriers, and improved life satisfaction (Heller et al., 2004; Penedo and Dahn, 2005). Ahn and Fedewa (2011) found that, compared with nondiagnosed individuals, physical activity had a fivefold greater impact on those diagnosed with cognitive impairment and a twofold greater effect on those diagnosed with emotional disturbance, suggesting that physical activity has the potential to improve the mental health of those most in need.

In sum, although more studies are needed, and there may be some differences in the magnitude and nature of the mental health benefits derived, it appears that physical activity is effective in improving mental health regardless of age, ethnicity, gender, or mental health status.

Sedentary Behavior

Sedentary behavior also influences mental health. Screen viewing in particular and sitting in general are consistently associated with poorer mental health (Biddle and Asare, 2011). Children who watch more television have higher rates of anxiety, depression, and posttraumatic stress and are at higher risk for sleep disturbances and attention problems (Kappos, 2007). Given the cross-sectional nature of these studies, however, the direction of these associations cannot be determined. A single longitudinal study found that television viewing, but not playing computer games, increased the odds of depression after 7-year follow-up (Primack et al., 2009; Biddle and Asare, 2011), suggesting that television viewing may contribute to depression. Because of design limitations of the available studies, it is unclear whether this effect is mediated by physical activity.

Television viewing also is associated with violence, aggressive behaviors, early sexual activity, and substance abuse (Kappos, 2007). These relationships are likely due to the content of the programming and advertising as opposed to the sedentary nature of the activity. Television viewing may affect creativity and involvement in community activities as well; however, the evidence here is very limited (Kappos, 2007). Studies with experimental designs are needed to establish a causal relationship between sedentary behavior and mental health outcomes (Kappos, 2007).

Although the available evidence is not definitive, it does suggest that sedentary activity and television viewing in particular can increase the risk for depression, anxiety, aggression, and other risky behaviors and may also affect cognition and creativity (Kappos, 2007), all of which can affect academic performance. It would therefore appear prudent for schools to reduce these sedentary behaviors during school hours and provide programming that has been shown to be effective in reducing television viewing outside of school (Robinson, 1999; Robinson and Borzekowski, 2006).

levels. Although more studies are needed to specify the exact neurological pathways that mediate this relationship, it appears that the favorable impact of physical activity on the prevention and treatment of depression may be the result of adaptations in the central nervous system mediated in part by neurotropic factors that facilitate neurogenerative, neuroadaptive, and neuroprotective processes (Dishman et al., 2006). It has been observed, for example, that chronic wheel running in rats results in immunological, neural, and cellular responses that mitigate several harmful consequences of acute exposure to stress (Dishman et al., 2006). A recent study found that children who were more physically active produced less cortisol in response to stress, suggesting that physical activity promotes mental health by regulating the hormonal responses to stress (Martikainen et al., 2013).

Psychological mechanisms that may explain why physical activity improves mental health include (1) distraction from unfavorable stimuli, (2) increase in self-efficacy, and (3) positive social interactions that can result from quality physical activity programming (Peluso and de Andrade, 2005) (see also the discussion of psychosocial health above). The relative contribution of physiological and psychological mechanisms is unknown, but they likely interact. Poor physical health also can impair mood and mental function. Health-related quality of life improves with physical activity that increases physical functioning, thereby enhancing the sense of well-being (McAuley and Rudolph, 1995; HHS, 2008).

Physical activity during childhood and adolescence may not only be important for its immediate benefits for mental health but also have implications for long-term mental health. Studies have shown a consistent effect of physical activity during adolescence on adult physical activity (Hallal et al., 2006). Physical activity habits established in children may persist into adulthood, thereby continuing to confer mental health benefits throughout the life cycle. Furthermore, physical activity in childhood may impact adult mental health regardless of the activity’s persistence (Hallal et al., 2006).

a varied regimen including both aerobic activities and strength training may be the most effective. Frequent episodes of physical activity are optimal given the well-substantiated short-term effects of physical activity on mental health status. Although there are well-substantiated physiological bases for the impact of physical activity on mental health, physical activity programming that effectively enhances social interactions and self-efficacy also may improve mental health through these mechanisms. Quality physical activity programming also is critical to attract and engage youth of all skills level and to effectively reach those at highest risk.

Sedentary activity may increase the risk of poor mental health status independently of, or in addition to, its effect on physical activity. Television viewing in particular may lead to a higher risk of such conditions as depression and anxiety and may also increase violence, aggression, and other high-risk behaviors. These impacts are likely the result of programming and advertising content in addition to the physiological effects of inactivity and electronic stimuli.

In conclusion, frequently scheduled and well-designed opportunities for varied physical activity during the school day and a reduction in sedentary activity have the potential to improve students’ mental health in ways that could improve their academic performance and behaviors in school.

Good health is the foundation of learning and academic performance (see Chapter 4 ). In children and youth, health is akin to growth. An extensive literature demonstrates that regular physical activity promotes growth and development and has multiple benefits for physical, mental, cognitive, and psychosocial health that undoubtedly contribute to learning. Although much of the evidence comes from cross-sectional studies showing associations between physical activity and various aspects of health, available prospective data support this cross-sectional evidence. Experimental evidence, although more limited for younger children, is sufficient among older children and adolescents to support the notion that children and young adults derive much the same health benefits from physical activity.

Moreover, many adult diseases have their origins in childhood. This finding, together with the finding that health-related behaviors and disease risk factors may track from childhood into adulthood, underscores the need for early and ongoing opportunities for physical activity.

Children’s exercise capacity and the activities in which they can successfully engage change in a predictable way across developmental periods. For example, young children are active in short bursts, and their capacity for continuous activity increases as they grow and mature (see Figure 3-2 ). In adults and likely also adolescents, intermittent exercise has much the same

FIGURE 3-2 Changes in physical activity needs with increasing age of children and adolescents. SOURCE: Adapted from Malina, 1991. Reprinted with permission from Human Kinetics Publishers.

benefit as continuous exercise when mode and energy expenditure are held constant. The health benefits of sporadic physical activity at younger ages are not well established. However, the well-documented short-term benefits of physical activity for some aspects of mental and cognitive health suggest that maximum benefit may be attained through frequent bouts of exercise throughout the day.

energy expenditure and help lessen the risk of excess weight gain and its comorbidities. Specific types of activities address specific health concerns. For example, vertical jumping activities contribute to energy expenditure for obesity prevention and also promote bone development (via the resulting ground reaction forces), potentially contributing to lower fracture risk. Other activities contribute to prevention of chronic disease. Since different types of physical activity contribute to distinct aspects of physical, mental, and psychosocial health, a varied regimen is likely to be most beneficial overall.

The quality of physical activity programming also is critical; psychosocial outcomes and improvements in specific motor skills, for example, are likely the result of programming designed specifically to target these outcomes rather than just a result of increases in physical activity per se. These psychosocial outcomes also are likely to lead to increased levels of physical activity in both the short and long terms, thereby conferring greater health benefits. Unstructured physical activity or free play also confers unique benefits and is an important supplement to more structured opportunities. Quality physical activity programming that makes these activities attractive, accessible, and safe for children and youth of all skill and fitness levels is critical to ensure that all youth participate in these activities and can therefore derive the health benefits.

Sedentary activities, such as screen viewing and excessive time spent sitting, may contribute to health risks both because of and independent of their impact on physical activity. Thus specific efforts in school to reduce sedentary behaviors, such as through classroom and playground design and reduction of television viewing, are warranted.

In sum, a comprehensive physical activity plan with physical education at the core, supplemented by other varied opportunities for and an environment supportive of physical activity throughout the day, would make an important contribution to children’s health and development, thereby enhancing their readiness to learn.

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Physical inactivity is a key determinant of health across the lifespan. A lack of activity increases the risk of heart disease, colon and breast cancer, diabetes mellitus, hypertension, osteoporosis, anxiety and depression and others diseases. Emerging literature has suggested that in terms of mortality, the global population health burden of physical inactivity approaches that of cigarette smoking. The prevalence and substantial disease risk associated with physical inactivity has been described as a pandemic.

The prevalence, health impact, and evidence of changeability all have resulted in calls for action to increase physical activity across the lifespan. In response to the need to find ways to make physical activity a health priority for youth, the Institute of Medicine's Committee on Physical Activity and Physical Education in the School Environment was formed. Its purpose was to review the current status of physical activity and physical education in the school environment, including before, during, and after school, and examine the influences of physical activity and physical education on the short and long term physical, cognitive and brain, and psychosocial health and development of children and adolescents.

Educating the Student Body makes recommendations about approaches for strengthening and improving programs and policies for physical activity and physical education in the school environment. This report lays out a set of guiding principles to guide its work on these tasks. These included: recognizing the benefits of instilling life-long physical activity habits in children; the value of using systems thinking in improving physical activity and physical education in the school environment; the recognition of current disparities in opportunities and the need to achieve equity in physical activity and physical education; the importance of considering all types of school environments; the need to take into consideration the diversity of students as recommendations are developed.

This report will be of interest to local and national policymakers, school officials, teachers, and the education community, researchers, professional organizations, and parents interested in physical activity, physical education, and health for school-aged children and adolescents.

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Why Physical Education Is Important

You already know that physical activity is an important part of your child’s health. But the benefits of physical education in schools go beyond the advantages of physical activity. Read on for some of the ways that physical education can improve your child’s health, happiness and overall well-being.

Physical Education Explained

Physical education, or PE, is a school subject that follows a curriculum based on the national standards for physical education for each grade level. In addition to giving kids a designated time to get exercise during the school day, PE also contributes to developing their cognitive skills, motor skills and emotional health. Studies have shown that kids who regularly attend PE are almost three times as likely to be physically active outside of school and nearly twice as likely to be active in adulthood.

Physical Benefits

Guidelines recommend that kids get at least 60 minutes of physical activity every day, and PE is a great way to help get those minutes in. Regular exercise builds strong bones and muscles as well as burns calories, and developing the habit when kids are young makes them much more likely to continue to take good care of themselves when they are adults. Exercising regularly can prevent obesity and decrease the likelihood of developing serious illnesses, such as heart disease, type 2 diabetes, cancer and osteoporosis.

Classroom Benefits

Studies have shown that kids who participate in PE have improved concentration, memory and classroom behavior. These perks lead to better academic performance, including higher grades and standardized test scores. Plus, kids who are physically active miss fewer days of school and have better long-term academic success.

Emotional Benefits

Kids who stay active are happier than those who don’t. This is because exercise builds confidence, promotes better sleep and produces endorphins, which are natural mood boosters. This can give kids a more positive outlook on life and help them to feel good about themselves.

If your physically active child experiences an injury, Augusta Health is here to help. Contact a provider at Pediatric Sports Medicine at the Children’s Hospital of Georgia at Augusta University .

About the author.

Children's Hospital of Georgia

Children’s Hospital of Georgia is the only facility in the area dedicated exclusively to children. It staffs the largest team of pediatric specialists in the region who deliver out- and in- patient care for everything from common childhood illnesses to life-threatening conditions like heart disorders, cancer and neurological diseases.

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Why PE matters for student academics and wellness right now

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This story about PE teachers was produced by The Hechinger Report , a nonprofit, independent news organization focused on inequality and innovation in education. Sign up for Hechinger’s newsletter .

Amanda Amtmanis, an elementary physical education instructor in Middletown, Connecticut, handed out cards with QR codes to a class of third graders, and told them to start running.

The kids sprinted off around the baseball field in a light drizzle, but by the end of the first lap, a fifth of a mile, many were winded and walking. They paused to scan the cards, which track their mileage, on their teacher’s iPad and got some encouragement from an electronic coach — “Way to run your socks off!” or “Leave it all on the track!”

A boy in a red Nike shirt surged ahead, telling Amtmanis his goal was to run 5 miles. “Whoa, look at Dominic!” another boy exclaimed.

“We don’t need to compare ourselves to others,” Amtmanis reminded him.

The third graders finished a third lap, alternating running and walking, and were about to start on a scavenger hunt when the rain picked up, forcing them inside. Amtmanis thanked her students for their willingness to adjust — a skill many of them have practiced far more often than running these past 18 months.

The full impact of the pandemic on kids’ health and fitness won’t be known for some time. But it’s already caused at least a short-term spike in childhood obesity Rates of overweight and obesity in 5- through 11-year-olds rose nearly 10 percentage points in the first few months of 2020.

Amtmanis’ “mileage club,” which tracks students’ running, both in and out of school, and rewards them with Pokémon cards when they hit certain targets, is an example of how PE teachers around the country are trying to get kids back in shape.

But inclement weather isn’t the only thing PE teachers are up against as they confront what might be called “physical learning loss.” Physical education as a discipline has long fought to be taken as seriously as its academic counterparts. Even before the pandemic, fewer than half the states set any minimum amount of time for students to participate in physical education, according to the Society of Health and Physical Educators (SHAPE), which represents PE and health instructors.

Now, as schools scramble to help kids catch up academically, there are signs that PE is taking a back seat to the core subjects yet again. In some California schools, administrators are shifting instructional minutes from PE to academic subjects — or canceling class altogether so PE teachers can sub for classroom teachers; in others, they’re growing class sizes in the gym, so they can shrink them in the classroom.

Meanwhile, innovative instructors like Amtmanis, who has worked in her district for more than 20 years, are struggling to get their ideas off the ground. Over the summer, the principal of Macdonough Elementary, one of two schools where Amtmanis teaches, approved her request to participate in another running program called The Daily Mile, in which kids walk or run 15 minutes a day during school hours.

Daily running breaks “boost attentiveness, which has positive effects on academics,” Amtmanis argued.

But two weeks into the school year, not a single teacher had bought into the idea.

“The issue is their packed schedule,” Amtmanis said.

Last year, many schools conducted gym class remotely, with students joining in from their bedrooms and living rooms.

The online format presented several challenges. Many students lacked the equipment, space, or parental support to participate fully. And many instructors grappled with how to teach and assess motor skills and teamwork online.

Though instructors found creative ways to keep students moving — substituting rolled-up socks for balls, and “disguising fitness” in scavenger hunts and beat-the-teacher challenges — they still fretted that online gym wasn’t giving students the same benefits as in-person classes.

Compounding their concern was the fact that many students were also missing out on recess and extracurricular sports.

In a March 2021 survey conducted by the Cooper Institute, maker of the popular FitnessGram assessments, close to half the PE teachers and school and district administrators responding said their students were “significantly less” physically active during their schools’ closure than before it.

Schools that reopened last year faced their own set of challenges, including bans on shared equipment that made even a simple game of catch impossible. Schools that were open for in-person learning were also much more likely to cut back on PE instructional time, or eliminate it altogether, the survey found.

The consequences of these reductions in physical activity are hard to quantify, especially since many schools suspended fitness testing during the pandemic and have yet to resume it, but some PE teachers say they’re seeing more kids with locomotor delays and weaker stamina than normal.

“The second graders are like first graders, and some are even like kindergarteners,” said Robin Richardson, an elementary PE instructor in Kentucky. They can jump and hop, she said, but they can’t leap. They’re exhausted after 20 seconds of jumping jacks.

An unusually high number of Richardson’s first graders can’t skip or do windmills. Some lack the spatial awareness that’s essential to group games.

“They don’t know how to move without running into each other,” she said.

Other instructors are seeing an increase in cognitive issues, such as difficulty paying attention or following directions, particularly among kids who remained remote for most or all of last year.

Kyle Bragg, an elementary PE instructor in Arizona, has seen kids sitting with their backs to him, staring off into space when he’s talking. “I say ‘Knees, please,’ so they spin around to face me,” he said.

And some PE teachers say their students’ social-emotional skills have suffered more than their gross motor skills. “They forgot how to share; how to be nice to each other; how to relate to each other,” said Donn Tobin, an elementary PE instructor in New York.

PE has a key role to play in boosting those skills, which affect how kids interact in other classes, said Will Potter, an elementary PE teacher in California.

“We’re uniquely situated to handle the social-emotional needs that came out of the pandemic, in a way classroom teachers are not,” Potter said.

Amtmanis, for her part, worries about her students’ mental health. She sees the little signs of strain daily — the kid who got upset because he couldn’t pick his group, for example, and the one who was distressed that his Mileage Club card had gotten mixed up in the front office.

“Their emotional reserves are low,” she said.

Yet not all instructors are reporting drops in their students’ fitness and skill development. Teachers in some middle- and upper-income districts said they haven’t noticed much of a change at all. In some communities, families seemed to spend more time outdoors.

“We saw the skyrocketing sale of bicycles, we saw families going for walks,” said Dianne Wilson-Graham, executive director of the California Physical Education and Health Project.

But in Title I schools like Macdonough, where more than half the students are low-income, some kids didn’t even have access to a safe place to exercise or play during school closures.

“Not only are they not in soccer leagues, but sometimes they don’t even have a park,” Amtmanis said.

Amtmanis came up with the idea of doing the Daily Mile after spring fitness tests revealed drops in her students’ strength, flexibility and endurance.

But many schools still aren’t sure how much physical learning loss their students have experienced as a result of the pandemic. Most schools pressed pause on fitness testing last year, and some elementary-school instructors are reluctant to restart it. They say the tests aren’t valid with young children, even in ordinary times, and argue the time they take could be better spent on Covid catch-up.

Andjelka Pavlovic, director of research and education for the Cooper Institute, said its tests are scientifically proven to be valid for students who are 10 and up, or roughly starting in fourth grade.

Fitness testing requirements vary by state, county or even district. Some states specify how often students must be tested; others leave it largely to the teacher.

Bragg, the Arizona teacher, said he has put testing “on the backburner” because “right now it’s not at the forefront of what’s important.”

Richardson said she is avoiding testing because she doesn’t want to use up precious instructional time or demoralize her students. “I want my kids to enjoy movement,” she said. If they perform poorly on the tests, “they may not feel as strong.”

In Connecticut, where schools are required to test fourth graders’ fitness annually, Amtmanis approached testing cautiously last year. She didn’t want to embarrass her students, so she made it into a series of games.

Instead of Sit-and-Reach, they had a “flexibility contest,” in which kids broke into teams for tag then had to perform stretches if they were tagged. She measured the distances stretched with curling ribbon, tied the ribbons together, and attached a balloon to the end. The team whose balloon soared the highest won fidget putty.

Pushups became a Bingo game, with the center space representing pushups.

“My goal was to get through it without ever using the words ‘fitness” or ‘testing,’” she said.

As the pandemic drags on, some instructors are taking a similar approach to fitness remediation and acceleration.

Bragg likes a warmup called “ Touch Spots ,” in which first graders listen as the instructor reads off the name of a color, then run and touch a corresponding dot on the floor. It works on reaction time, cardiovascular endurance, spatial awareness and sequencing — but the kids don’t know that.

“Students are having so much fun that they don’t realize how much fitness they are doing,” Bragg said.

Differentiation — tailoring instruction to meet individual students’ needs — has become even more essential, with former remote learners often lagging behind their in-person peers, Bragg said.

When playing catch, for example, he offers his students different sized balls — the smaller ones are more challenging.

Potter, the California teacher, spent the first two weeks of school teaching his students how to connect with their partners, stressing the importance of eye contact and body language.

“When you’re on Zoom, you look at the camera to make eye contact,” he said. “It’s a very different environment.”

Bragg reminds his students how to include kids who are standing on the sidelines, modeling excited body language and tone of voice. Lately, he’s noticed that kids who were remote last year are being excluded from groups.

“Social interaction needs to be practiced, just like how to throw a ball,” he said.

Richardson, the Kentucky PE teacher, is trying to build up her students’ stamina gradually, through progressively longer intervals of exercise.

But she works in a school with pods, so she sees each group of kids for five consecutive days, every third week. The two weeks in between, she has to hope that teachers will provide recess and “movement breaks.” She’s trying to get them to give kids breaks “when they get glassy-eyed and frustrated.”

Recently, Richardson was at a staff training session at which depleted teachers were “popping candy in the back.” When she raised her hand and requested a break in the training, her colleagues cheered. She told them to remember how they felt when their students return to the building.

“I always say, ‘If your bum is numb, your brain is the same,’” she said.

Convincing classroom teachers to set aside more time for movement can be challenging, though. As students return from months of online learning, teachers are under enormous pressure to get them caught up academically.

Kate Cox, an elementary and middle-school PE teacher in California, wishes schools would “realize what they’re missing when they cut PE because of learning loss in other areas.” Physical education is “readying their minds and bodies to be more successful in other areas,” Cox said.

Terri Drain, the president of SHAPE, argued that schools fail students when they treat physical learning loss as less serious than its academic counterpart.

“In the primary grades, children develop fundamental motor skills, such as throwing, catching, running, kicking and jumping,” she said. Unless schools commit to helping kids catch up, “the impacts of this ‘missed learning’ will be lifelong.”

In Connecticut, Amtmanis hasn’t given up on convincing teachers to carve out time for the Daily Mile. She recently sent them a list of suggestions on how to fit 15 minutes of running into the day, including by incorporating it as an active transition between academic blocks.

“While it may seem like there aren’t minutes to spare,” she wrote, “the energizing effect of the active transition should result in more on-task behavior and more efficient working.”

In the meantime, Amtmanis plans to keep using the mileage club to motivate her students to run and to monitor their progress.

“I don’t want to call attention to the fact that not everyone is fit,” she said. “This is an unobtrusive way to keep the data.”

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Why is physical education so important.

August 11, 2020

It is no secret that appropriate physical activity is necessary to a student’s overall well-being. The benefits of physical education in schools are far-reaching, including both increased student physical health and better academic performance. Physical education is more than just running around a track or kicking a ball. It teaches children key life skills alongside improving their health and wellbeing. Obesity continues to rocket across the globe and more people are taking on sedentary lifestyles. Promoting a positive mindset about exercise from an early age will help to keep them healthy as they get older.

In recent years, many schools have cut back on their physical education programmes, placing greater emphasis on academics as they strive to prepare students for college and the workforce. Yet research shows that adults who had regular PE classes in school are more than twice as likely to be physically active as their non-PE counterparts. In fact, children who have regular Physical Education lessons at school will be likely to experience the following benefits:

Physical and Mental Health

Well-versed in child development, PE teachers ensure that the curriculum consists of age-appropriate activities that support growing minds and bodies. They will adapt lessons to make them appropriate for their groups and ensure that they do not overwhelm children with skills or requirements that may be too advanced. At the same time, they know when students are ready to be pushed. PE improves motor skills and increases muscle strength and bone density, which in turn makes students more likely to engage in healthy activity outside of school. Furthermore, it educates children on the positive benefits of exercise and allows them to understand how good it can make them feel.

Participating in PE puts children on track to make regular exercise a habit– one that can combat obesity and reduce the likelihood of developing chronic conditions such as heart disease and diabetes. It also helps to maintain their brain and mental health. By making exercise ‘normal’ from an early age this becomes ingrained in them throughout their lives.

Physical education motivates children to expand their skills, as grasping the fundamentals of one sport makes it easier to master the rules of another. Since students spend a considerable amount of time in school, it is an ideal setting to empower them to take responsibility for their health. Often a secondary benefit of physical education is that children become more aware of what they are putting in their bodies. They realise the importance of a healthy, balanced diet and that sugary snacks are not the best way to gain energy for their sport. They will often want to find out more about their bodies and this again teaches them to care for themselves and others.

Studies also suggest that students who are less active are more likely to experience sleep disorders. Regular exercise reduces stress and anxiety, contributing to healthy sleep patterns, which in turn lead to better mental health, immune system functioning, and overall well-being.

‍ Social Skills

Physical education that begins in early childhood demonstrates the value of cooperation, while being part of a team gives them a sense of identity. When PE teachers model prosocial behaviours, children gain skills that pave the way for healthy interactions and relationships throughout life. This teaches them essential communication skills and social skills. It helps them become team players, work alongside a diverse range of team mates and be able to support others.

Learning the fundamentals of popular sports also provides a constructive way for students to fit in with their peers, especially as they approach adolescence. Being able to understand a range of sports or hobbies allows them to be part of something bigger than their classroom. They may find a real passion for a particular sport, start attending sporting fixtures and they may even go on to have a career within the sporting industry. Having the opportunities to ignite this type of passion whilst developing a range of skills is hugely important.

Self-Esteem and Character Development

Playing team sports in a structured setting reinforces leadership and good sportsmanship. Playing various roles on a team and gaining new skills encourage students to respect themselves and their peers. It also teaches them to be understanding to others and support them through their difficulties.

Gestures such as a hand shake, a pat on the back or a high-five from a team-mate helps to build confidence and camaraderie, and earning praise from coaches or other players also helps to improve self-esteem. This then leads to increasing children’s confidence to trust their abilities and to progress their skills within their sport. It is important for children to understand that self-esteem should not rely on winning or losing, but in the taking part and learning from every opportunity. Children who receive constructive criticism well are shown to be better at making changes to improve themselves, whether it be at school, in work or in sport.

As they hone their abilities through individual and team sports, children learn self-discipline and goal-setting. They learn that there will always be winners and losers but that it is important to accept this and to get back up when needed, or in turn to encourage those around us to carry on.

Discipline is essential for sport and this can be both mental and physical. In sport, children need to follow rules and take orders from their coaches. Sometimes they must accept decisions that they may not agree with. This teaches them an important life skill that will help them throughout their life and careers. According to the International Platform on Sport and Development, “Sport has been used as a practical tool to engage young people in their communities through volunteering, resulting in higher levels of leadership, community engagement and altruism among young people.”

Better Academic Performance

The many benefits of PE carry over from the playing field or gymnasium into the classroom, leading to better academic performance. Research reveals that children who take part in physical education are better able to regulate their behaviour and stay focused in class. Often sport gives children the opportunity to take their minds off their academic studies. It offers the chance for them to relax, release pent up emotions and to spend time having fun with their friends.

At OWIS, PE is a critical component of a well-rounded curriculum. To learn more, visit our Sports Programme page.

(This blog was originally written in collaboration with Ms Marisa Healy, former Physical Education (PE) Teacher, OWIS Nanyang.)

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Physical Health and Education: A Life-Long Journey

Physical health and education are foundational to well-being across all stages of life. From early childhood through to the later years, the benefits of maintaining an active lifestyle and continual learning about health are vast and well-documented. Despite this, many view physical education as a priority only during school years, neglecting its importance as we age.

Understanding the principles of physical health and the best practices for maintaining it are crucial for enhancing quality of life and preventing a range of chronic diseases. Education in this field not only teaches us the mechanics of physical activity but also instills the skills necessary to navigate the challenges of mental health, nutrition, and overall wellness.

Below, we aim to redefine these perceptions by exploring the enduring value of physical health and education, why physical education should be an ongoing pursuit, and how it can be realistically integrated into our daily lives at any age.

What Is Physical Health and Education

What is physical health and education, exactly? Physical health extends beyond merely an absence of illness: It's a state of complete physical well-being that enables individuals to thrive in their daily activities and long-term pursuits. It forms the core of our ability to enjoy life and meet the challenges of aging, work, and mental stress. By fostering a strong foundation of physical health, we equip ourselves with the resilience to withstand the physical demands of life and the agility to recover from setbacks.

Defining Physical Health in Modern Society

In the context of today, physical health encompasses a state of well-being that includes the effective functioning of all body systems and parts, as well as a person's ability to engage in daily activities without physical constraint. This broad definition acknowledges that physical health impacts various aspects of life by influencing an individual's capacity to perform and enjoy daily tasks. Factors such as lifestyle choices, genetic predispositions, and environmental conditions play central roles in shaping one's physical health.

Regular physical activity, adequate sleep, balanced nutrition, and effective stress management are all critical components that contribute to maintaining and improving physical health. This contemporary understanding encourages a comprehensive approach, emphasizing the importance of a harmonious balance between physical capabilities and environmental demands.

The Connection Between Physical Health and Overall Well-Being

Physical health significantly impacts overall well-being , serving as a cornerstone for mental and emotional health. Regular physical activity strengthens the body and mental health by reducing symptoms of anxiety and depression. It promotes the release of endorphins, known as "feel-good" hormones, which elevate mood and foster feelings of happiness.

Additionally, a balanced diet rich in nutrients supports brain function and can influence mood and cognitive abilities, while sufficient sleep is essential for emotional regulation and mental resilience. The interplay between these elements of physical health and mental well-being demonstrates the profound connection between the two to achieve a balanced, fulfilling life.

The Role of Education in Promoting Physical Health

To further answer what physical health and education is, it’s worth noting that education plays a pivotal role in promoting physical health by equipping individuals with the knowledge and skills necessary to make informed decisions about their lifestyles. Through structured learning, both formal and informal, people of all ages can understand the importance of physical activity, nutrition, mental well-being, and preventive healthcare measures. The right educational strategies can communicate the benefits of physical health and be integrated throughout different stages of life to cultivate a healthier society.

Let’s dive into how educational initiatives and programs can heavily influence public health outcomes by fostering a culture of health awareness and proactive behavior.

Integrating Physical Health Into School Curricula

When discussing what health and physical education is in the school setting, it’s critical to look at the current curricula. Integrating physical health into school curricula has been gaining traction as an innovative approach to elevate educational outcomes and student well-being.

A notable initiative, the "Thinking While Moving in English" program in Australia, exemplifies this trend by blending physical activity with English lessons. This method helps meet physical activity requirements and stimulates cognitive functions like memory and attention, which are essential for academic performance. The integration of movement-based learning into traditionally sedentary subjects such as English offers a dual benefit of improving physical health and enhancing literacy skills, making a compelling case for the holistic development of students.

Lifelong Learning: Continuing Education Beyond the Classroom

Continuing education and lifelong learning are vital aspects of personal, professional, and physical development, transcending the traditional classroom to provide varied and flexible learning opportunities. These programs are structured to accommodate the wide-ranging needs of a diverse learner base, offering a range of educational experiences from short-term workshops to extensive courses, both online and in person. Whether it’s with the goal of pursuing physical education or health sciences as a career or simply staying informed on how to maintain your own health, ongoing learning is key to achieving and maintaining professional competence and fulfillment.

Key Components of Physical Health

Physical health is a multi-faceted concept that encompasses several critical elements, each contributing uniquely to overall well-being and functionality. Understanding these components is key to developing a comprehensive approach to health that can be maintained throughout life. By examining the core aspects of physical health—including cardiovascular fitness, muscle strength, flexibility, nutrition, and mental wellness—we can better appreciate how they interact and contribute to a healthy lifestyle.

Nutrition and Diet: Fuel for a Healthy Body

Nutrition and diet play a fundamental role in maintaining physical health by providing necessary fuel and nutrients for the body's optimal functioning. A balanced diet rich in fruits, vegetables, proteins, and whole grains supports overall health, helping prevent conditions like obesity, heart disease, and diabetes. It also contributes to stronger immune systems, elevated mood, and better energy levels, which are essential for daily activities and long-term health.

Exercise and Fitness: Building Blocks of Physical Health

Exercise and fitness are foundational to maintaining and enhancing physical health. Engaging regularly in physical activity not only strengthens the cardiovascular system, thereby improving heart and lung efficiency, but it also builds muscle strength and endurance. This increased physical capability makes daily activities easier and can reduce fatigue. In addition, regular exercise contributes substantially to weight management, helps prevent chronic diseases like type 2 diabetes and cardiovascular problems, and improves mental health by reducing symptoms of depression and anxiety. Importantly, exercise is not just about physical benefits; it also offers psychological boosts by improving self-esteem and confidence.

Challenges to Maintaining Physical Health

Maintaining physical health in the modern world presents a variety of challenges that can hinder individuals from achieving and sustaining a healthy lifestyle. These obstacles range from environmental factors, such as urbanization and the prevalence of sedentary jobs, to personal issues like lack of motivation, time constraints, and financial limitations. By understanding these hurdles, individuals can better navigate the complexities of modern life and find effective strategies to overcome them, ensuring a more consistent and proactive approach to health and wellness.

Navigating the Obstacles of Modern Lifestyle

Modern lifestyles present numerous obstacles to maintaining physical health that can make it challenging to commit to a healthier routine. A significant barrier for many is a general lack of time due to work and family obligations, which pushes physical activity to the backburner. Addressing this requires strategic planning regarding how to integrate activity into daily routines, utilize local resources, and engage in physical activities that do not require extensive time commitments or travel.

Unfortunately, modern work environments and social norms can also discourage active lifestyles. Overcoming this involves seeking support from friends and family, finding group activities, and leveraging community resources to maintain motivation and access to necessary facilities.

The Impact of Technology on Physical Activity

While often seen as a contributor to sedentary lifestyles, technology holds the potential to enhance physical activity , too. Innovations such as fitness apps and wearable devices incorporate behavioral change techniques (like goal-setting and feedback) that have been shown to motivate increased physical activity. These technologies offer accessible and user-friendly ways to track health metrics, encouraging consistent physical engagement.

For children, the integration of active video games and health-focused apps suggests a positive direction in promoting physical activity, despite the concerns about screen time. This complex relationship between technology and physical activity underscores the value of strategic technological integration to support health and fitness goals.

Physical Education: Beyond Just Physical Fitness

Physical education encompasses far more than the mere improvement of physical fitness in the gymnasium or on the sports field. It serves as a platform for personal and social development along with instilling life skills such as teamwork, perseverance, and leadership. It aims to enhance students' physical capabilities and focus on promoting psychological and emotional growth. Through structured activities and sports, physical education teaches valuable lessons about cooperation, respect for others, and the importance of a balanced lifestyle.

Developing Skills for Teamwork and Leadership

Physical education plays a crucial role in cultivating teamwork and leadership skills among students. Through sports and various physical activities, children enhance their physical abilities and develop essential life skills such as effective communication, problem-solving, and leadership. These activities require them to work collaboratively, strategize together, and support each other toward achieving common goals. Such experiences are instrumental in building foundational elements of teamwork like trust and cooperation among peers. This process both benefits their interpersonal relationships and prepares them for future professional environments where teamwork is often critical to success.

Enhancing Emotional and Mental Health Through Physical Activity

Physical activity is a powerful tool for enhancing emotional and mental health. Regular engagement in exercises such as walking, running, or team sports can significantly mitigate symptoms of depression and anxiety . The immediate benefits include mood improvement and increased feelings of well-being. Physical activity helps by releasing endorphins, chemicals in the brain that act as natural painkillers and mood elevators. It also contributes to better sleep, which is necessary for emotional and mental stability.

Exercising can help manage stress more effectively as well. By setting achievable fitness goals and viewing physical activity as a regular part of life, individuals can foster a more positive attitude towards exercise and its benefits. Physical activity should be tailored to fit personal capabilities and preferences to maintain consistency and enjoy long-term benefits. Consistent physical activity is linked to reductions in feelings of depression and anxiety, along with improved cognitive functions and a lower risk of cognitive decline in older adults.

Innovations in Physical Health and Education

The field of physical health and education is undergoing a transformation, fueled by advances in technology and a deepening understanding of human physiology and psychology. From wearable fitness technology that tracks physiological data to interactive learning platforms that make physical education more engaging, these cutting-edge innovations are shaping the future of how we approach physical education and overall health management. They promise to boost the effectiveness of fitness and health education programs.

The Rise of Digital Fitness and Wellness Platforms

The rise of digital fitness and wellness platforms has considerably reshaped the landscape of physical health by offering more personalized, flexible, and engaging ways to maintain fitness. Innovations like Peloton and ClassPass Live leverage live streaming and interactive technology to bring the energy and accountability of studio classes right into the home. These platforms offer a variety of classes, from high-intensity workouts to yoga and meditation, often with real-time feedback and communal leaderboards that promote a sense of competition and community among users. This model replicates the in-person class experience and expands the reach and accessibility of fitness programs, making it easier for more people to integrate regular exercise into their daily routines.

Incorporating Mindfulness and Yoga into Physical Education

Incorporating mindfulness and yoga into physical education programs enriches the experience by enhancing both physical and mental wellness. These practices help students develop better stress management techniques and emotional resilience. Implementing yoga in the curriculum typically begins with teacher-led sessions to establish a foundation of basic poses and mindful practices. As students become more familiar, the activities can evolve into more autonomous forms like circuit yoga, fostering greater engagement and personal investment in their own health. This method boosts physical flexibility and balance as well as cultivates mental focus and a sense of calm.

The Future of Physical Health and Education

The future of physical health and education looks to integrate more seamlessly with technological advancements and evolving educational methodologies. Innovations like virtual reality and AI-driven fitness programs are poised to transform how physical education is delivered, making it more personalized and accessible. As we continue to understand more about the human body and the benefits of a physically active lifestyle, educational approaches and public health policies are likely to adapt to further incorporate these insights to help shape a healthier, more informed society.

Policy Changes and Their Impact on Public Health Initiatives

Policy changes can significantly affect public health initiatives, as evidenced by efforts to combat health emergencies through public health and social measures (PHSM). These interventions , which include guidelines on mask-wearing, hand washing, and social distancing, have been central to managing disease transmission. Effective policies can strengthen the collective response to health crises and ensure that both preventative and reactionary measures are efficiently implemented to safeguard community health.

Preparing the Next Generation for a Healthier Tomorrow

Priming future generations for the health needs of tomorrow, with programs like the National Governors Association's initiative providing key resources and training to states. This initiative aims to build a competent healthcare workforce equipped with the necessary skills and knowledge to address evolving needs. Additionally, organizations like the Alliance for a Healthier Generation enhance child and youth health by promoting physical, mental, and social well-being through outreach to schools and communities, ensuring that young people develop healthy habits supported by their environments.

Prepare Our Youth For a Healthier Future With a Degree in Health and Physical Education

If you're passionate about making a lasting impact in health and physical education, consider applying to the bachelor’s degree program in health and physical education at University of the Cumberlands. This curriculum is designed to equip you with the knowledge and skills needed to promote physical health and wellness in educational settings and beyond.

Take the first step toward a fulfilling career by exploring more about this program and joining a community of like-minded professionals committed to shaping a healthier future. Learn more by requesting further information , or apply today !

Physical Education Schools

What is the impact of physical education on students’ well-being and academic success?

Decreasing time for quality phys-ed to allow more instructional time for core curricular subjects – including math, science, social studies and English – is counterproductive, given its positive benefits on health outcomes and school achievement.

by: Lee Schaefer , Derek Wasyliw

date: June 25, 2018

Download and print the Fact Sheet (232.30 kB / pdf)

What is the impact of physical education on students' well-being and academic success?

Research confirms that healthier students make better learners. The term quality physical education is used to describe programs that are catered to a student’s age, skill level, culture and unique needs. They include 90 minutes of physical activity per week, fostering students’ well-being and improving their academic success. However, instructional time for quality phys-ed programs around the world are being decreased to prioritize other subject areas (especially math, science, social studies and English) in hopes to achieve higher academic achievement. However, several studies have identified a significant relationship between physical activity and academic achievement. Research also demonstrates that phys-ed does not have negative impacts on student success and that it offers the following physical, social, emotional and cognitive benefits:

Quality phys-ed helps students understand how exercise helps them to develop a healthy lifestyle, gain a variety of skills that help them to participate in a variety of physical activities and enjoy an active lifestyle.

Quality phys-ed provides students with the opportunity to socialize with others and learn different skills such as communication, tolerance, trust, empathy and respect for others. They also learn positive team skills including cooperation, leadership, cohesion and responsibility. Students who play sports or participate in other physical activities experience a variety of emotions and learn how to better cope in stressful, challenging or painful situations.

Quality phys-ed can be associated with improved mental health, since increased activity provides psychological benefits including reduced stress, anxiety and depression. It also helps students develop strategies to manage their emotions and increases their self-esteem.

Research tends to show that increased blood flow produced by physical activity may stimulate the brain and boost mental performance. Avoiding inactivity may also increase energy and concentration in the classroom.

Therefore, decreasing time for quality phys-ed to allow more instructional time for core curricular subjects – including math, science, social studies and English – is counterproductive, given its positive benefits on health outcomes and school achievement.

Additional Information Resources

PHE Canada (2018). Quality daily physical education . Retrieved from https://phecanada.ca/activate/qdpe

Ontario Ministry of Education. (2005). Healthy schools daily physical activity in schools grades 1 ‐ 3. Retrieved from http://www.edu.gov.on.ca/eng/teachers/dpa1-3.pdf

Ardoy, D. N., Fernández‐Rodríguez, J. M., Jiménez‐Pavón, D., Castillo, R., Ruiz, J. R., & Ortega, F. B. (2014). A Physical Education trial improves adolescents’ cognitive performance and academic achievement: The EDUFIT study. Scandinavian journal of medicine & science in sports , 24 (1).

Bailey, R., Armour, K., Kirk, D., Jess, M., Pickup, I., Sandford, R., & Education, B. P. (2009). The educational benefits claimed for physical education and school sport: An academic review. Research papers in education , 24 (1), 1-27.

Beane, J.A. (1990). Affect in the curriculum: Toward democracy, dignity, and diversity . Columbia: Teachers College Press.

Bedard, C., Bremer, E., Campbell, W., & Cairney, J. (2017). Evaluation of a direct-instruction intervention to improve movement and pre-literacy skills among young children: A within-subject repeated measures design. Frontiers in pediatrics , 5 , 298.

Hellison, D.R., N. Cutforth, J. Kallusky, T. Martinek, M. Parker, and J. Stiel. (2000). Youth development and physical activity: Linking universities and communities. Champaign, IL: Human Kinetics.

Ho, F. K. W., Louie, L. H. T., Wong, W. H. S., Chan, K. L., Tiwari, A., Chow, C. B., & Cheung, Y. F. (2017). A sports-based youth development program, teen mental health, and physical fitness: An RCT. Pediatrics , e20171543.

Keeley, T. J., & Fox, K. R. (2009). The impact of physical activity and fitness on academic achievement and cognitive performance in children. International Review of Sport and Exercise Psychology , 2 (2), 198-214.

Kohl III, H. W., & Cook, H. D. (Eds.). (2013). Educating the student body: Taking physical activity and physical education to school . National Academies Press.

Rasberry, C. N., Lee, S. M., Robin, L., Laris, B. A., Russell, L. A., Coyle, K. K., & Nihiser, A. J. (2011). The association between school-based physical activity, including physical education, and academic performance: a systematic review of the literature. Preventive medicine , 52 , S10-S20.

Sallis, J. F., McKenzie, T. L., Kolody, B., Lewis, M., Marshall, S., & Rosengard, P. (1999). Effects of health-related physical education on academic achievement: Project SPARK. Research quarterly for exercise and sport , 70 (2), 127-134.

Strong WB, Malina RM, Blimkie CJ, Daniels SR, Dishman RK, Gutin B, Hergenroeder AC, Must A, Nixon PA, Pivarnik JM, Rowland T, Trost S, & Trudeau F (2005). Evidence based physical activity for school-age youth. Journal of Pediatrics . 146(6):732–737.

Trudeau, F., & Shephard, R. J. (2008). Physical education, school physical activity, school sports and academic performance. International Journal of Behavioral Nutrition and Physical Activity , 5 (1), 10.

Beane, J. A. (1990). Affect in the curriculum: Toward democracy, dignity, and diversity . Columbia University, New York, NY: Teachers College Press.

Meet the Expert(s)

Lee schaefer.

Assistant Professor in the Kinesiology and Physical Education Department at McGill University

Lee Schaefer is an Assistant Professor in the Kinesiology and Physical Education Department at McGill University. His work is generally focused on teacher education and teacher knowle...

Derek Wasyliw

Master’s student in the Kinesiology and Physical Education Graduate Program at McGill University

Derek Wasyliw is a second-year Master’s student in the Kinesiology and Physical Education Graduate Program at McGill University. He is the proud recipient of the 2017-2018 SSHRC Jo...

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Physical Education is just as important as any other school subject

Lecturer in Physical Education, University of Central Lancashire

Senior Lecturer in PE and Sports Studies, University of Central Lancashire

Disclosure statement

Andrew Sprake is affiliated with the North Western Counties Physical Education Association and FIEP in a voluntary capacity.

Clive Palmer does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.

University of Central Lancashire provides funding as a member of The Conversation UK.

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Bahasa Indonesia

Physical Education (PE) is often viewed as a marginal subject within the curriculum. And many secondary schools actively reduce PE time to make way for what are deemed more “serious” or “important” subjects.

Research from the Youth Sport Trust shows that 38% of English secondary schools have cut timetabled PE for 14- to 16-year-olds. One of the main reasons for this is the increased pressure to produce exam results . Much of the time pupils would usually spend in PE lessons is now spent receiving extra tutoring on topics other than PE.

Despite these cuts, however, PE is still championed for its potential to promote health and encourage lifelong physical activity. This is an important issue given that over 30% of year six pupils are classed as “overweight” or “obese” according to the latest government figures .

PE is also praised for its contribution to improved psychological health , for helping to nurture social and moral development – as well as supporting cognitive and academic performance .

The Association for Physical Education maintains that high quality PE fosters the physical, moral, social, emotional, cultural and intellectual development of pupils. But the many aims for PE – such as health promotion, skills development as well as a focus on social and moral issues – has resulted in confusion about the subject and has done little to further the educational experiences in practice. In fact, it has been argued that PE offers more entertainment than education .

Not intellectual enough

A waste of time and a bit of entertainment, or vitally important to the education and development of a child – which is it?

Part of the problem seems to be that PE is often viewed as an opportunity for pupils to be active and to enjoy themselves. Or in some cases, as a form of stress relief and to serve as a break from traditional learning.

Clearly, these areas are valuable for pupils’ general well-being and there is a growing evidence base to suggest that physical activity has the potential to support learning more broadly . But the role of PE is not merely to prop up and support pupils’ learning in other subjects. Instead, it should provide meaningful learning experiences within the subject itself.

What PE seemingly lacks in comparison to all other subjects is a platform on which pupils’ learning can be communicated and evidenced with clarity and rigour. And while PE is often marginalised to make way for more valuable or academic subjects, it seems the intellectual and academic value of PE itself is largely overlooked.

The potential of PE

PE, sport and physical culture each offer a unique platform on which to explore a multitude of holistic learning opportunities. For instance, the ethical or moral controversies in sport can give teachers a range of educational stimuli for debate, reasoning and critical thinking.

The Sports Monograph is a recent project we worked on, which invited learners to collaborate and share their opinions and experiences about sport and what it means to them. The project included primary and secondary school pupils, as well as undergraduate and postgraduate students, who were all supported by their teachers and lecturers.

As part of the project, not only were the pupils recognised for their written contributions at school awards evenings, but unlike in traditional PE, their work left a trail of learning evidence and intellectual engagement – which the schools recognised and celebrated. PE was effectively standing shoulder to shoulder with other subjects in the curriculum as a valuable educational endeavour, with written evidence to support the claim. These pupils now have publications that are being used to teach undergraduate students at the University of Central Lancashire.

Future health

The spiralling downtrend of PE time in secondary schools is a major cause for concern and it would seem that PE is in urgent need of an overhaul. But while the future of PE may be uncertain, there are certainly many opportunities for cross-curricular links and integrative learning in PE.

A recent project, for instance, explored the link between cycling and wider conceptual learning. Similarly, another recent study explored the physical aspects of learning across all curriculum areas, simply through setting up a tent .

The role that PE can play as part of the wider academic curriculum seems to be, at best understated, and at worst, completely overlooked. Activities like the ones raised here could help to broaden the educational potential of PE, encourage more pupils to engage with the subject and strengthen the place of PE as a unique and valuable educational pursuit. The opportunities are there, but PE must be ready to grasp them and let the pupils write about their sporting passions to reflect what they are said to be learning.

Physical education

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Physical education is an important part of the daily curriculum for all students. It has been proven to have many positive effects on students’ physical, emotional, and mental well-being.

Whether it’s playing sports, going for a jog, or participating in physical activities, physical education can help students develop a healthy lifestyle that can be sustained for years to come.

But what are the 10 importance of physical education?

In this article, we will discuss the 10 most important benefits of physical education, including improved physical health, increased focus and concentration, better social skills, enhanced coordination and balance, improved mental health, and more.

Read on to learn why physical education is so important!

1. Improves Quality of Life

Physical education offers numerous benefits to kids, teens, and adults alike. From increased fitness levels to improved mental health, engaging in physical activity is key for leading a healthy lifestyle.

Physical education helps individuals of all ages learn the importance of activity and how it can enhance their quality of life. This includes learning how to properly exercise and practice good eating habits, as well as gaining an understanding of the benefits that come from living an active lifestyle.

By taking part in physical activities, such as team sports and dance classes, participants gain a sense of community while improving their physical and emotional well-being.

2. Enhances Cognitive Performance

Physical education can have a positive impact on cognitive performance. Studies show that physical activity increases the levels of dopamine and serotonin, which are neurotransmitters that help to improve brain function and enhance concentration, focus, and creativity.

This means that students who are physically active tend to perform better in school as they are more alert, attentive, and motivated to learn. Additionally, aerobic activities such as running or swimming can increase oxygen flow to the brain, which can also lead to improved mental clarity.

Thus, physical education classes provide an invaluable opportunity for students to stay fit while improving their academic performance.

3. Develops Physical Strength and Endurance

Physical education helps to build physical strength and endurance by providing activities that challenge the body. This can help reduce the risk of injury since muscles and joints become stronger, as well as improve balance and coordination.

Regular physical activity can also aid in weight control, reducing the risk of obesity and chronic diseases like diabetes.

Additionally, regular physical activity can increase energy levels, improve sleep quality, reduce stress levels, and even improve mental focus and concentration.

4. Enhances Social Skills

Physical education can help students to develop strong social skills. Through physical education classes, students learn how to work together as a team to reach common goals.

This teaches the importance of collaboration, communication, and problem-solving, which are all essential life skills.

Additionally, physical education classes provide an opportunity for students to build friendships with their peers and foster a sense of community.

5. Reduces Stress and Anxiety

Physical education is an important part of any child’s development and has been linked to reducing stress and anxiety. Research suggests that physical activity can help lower blood pressure and cortisol levels.

This can be particularly beneficial for children who may experience high levels of stress or anxiety due to social pressures in school or home life. Taking part in physical activities, such as team sports, allows children to exercise their bodies while also giving them the opportunity to socialize with teammates and coaches.

This helps create a supportive environment where children can build relationships with their peers and trust adults outside of the family setting.

Regular physical activity also encourages children to take care of their mental health by providing them with an outlet for their emotions, as well as teaching them skills for managing stress effectively.

6. Prevents Chronic Diseases

Physical education plays an important role in preventing chronic diseases. Regular physical activities can lower the risk of developing heart disease, stroke, diabetes, and certain types of cancer.

It can also help reduce blood pressure and cholesterol levels as well as improve overall health. Additionally, physical education helps keep our bones strong and reduces the risk of osteoporosis.

Finally, regular exercise can help with stress management and reduce depression symptoms.

7. Improves Self-Image and Confidence

Physical education provides an opportunity for children to develop confidence and self-image. Participating in physical activities helps children to feel good about their bodies and build a positive self-image.

It also encourages them to challenge themselves, which can lead to increased confidence in other areas of their lives.

Physical education classes also provide a safe environment for children to make mistakes and learn from them, further improving their confidence and self-esteem.

8. Teaches Teamwork and Cooperation

Physical education allows students to work together in teams and learn how to cooperate with each other. This is an important skill that will help them later in life when they become part of a team in the workplace.

It teaches kids to be team players, respect each other’s differences, and understand how to work together toward a common goal.

Physical education also encourages healthy competition, which can lead to improved sportsmanship. Students will learn how to win gracefully and lose with dignity, all while becoming better teammates.

9. Promotes Healthy Eating Habits

Physical education helps promote healthy eating habits. By teaching students about the benefits of eating nutritious foods, physical education encourages them to make healthier food choices throughout their lives.

Through physical activity, students also learn about how their bodies work and how certain foods will help fuel their energy levels for activities.

Additionally, physical education can teach students about portion control and how to maintain a balanced diet. This is important for both short-term and long-term health goals.

10. Increases Attention Span

Physical education helps to increase attention span, which can help students stay focused for longer periods of time.

Studies have shown that physical activity can improve an individual’s ability to concentrate and process information more quickly. As such, this can be beneficial for students who have difficulty paying attention in class or studying for long periods of time.

Furthermore, physical education encourages active participation, which allows students to engage with the content in a different way than they would if they were just sitting and listening.

Final Words

Physical education provides numerous benefits to children, youth, and adults. It develops physical skills, increases muscular strength, boosts cardiovascular health and endurance, reduces stress, and helps people maintain a healthy weight.

Physical education has been proven to increase academic performance, improve mental focus and concentration, reduce depression and anxiety symptoms, strengthen social bonds within a community, develop leadership skills, enhance creative problem-solving abilities, and foster self-confidence.

With all these advantages in mind, it is clear that physical education is an essential part of any educational program.

Key Takeaways

Physical education is an important part of a student’s overall development.
It helps to build the skills and habits that are necessary for leading a healthy, active lifestyle.
It can lead to improved physical fitness, enhanced cognitive performance, better social skills, reduced stress and anxiety, improved self-image and confidence as well as increased attention span.

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10 Reasons Why Physical Education is Important

This article will give you in-depth information about the importance of physical education in schools.

Physical education is important because it enhances the overall quality of life, promotes health and well-being, fosters friendships and teamwork skills, and develops lifelong healthy habits.

Since time immemorial, physical education has played a crucial role in the lives of human beings. Exercise and physical activity have been proven to have many benefits for both the body and the mind.

Physical education aims to empower students to make wise use of their energy, effort, and time by studying in a fruitful way. The ultimate purpose of physical education is not just to train a student’s body but also to train his/her mind.

What is Physical Education?

Physical education (P.E), also known as gym classes, is an activity used to enhance fitness and agility through exercise and physical activity. Some define it as an educational approach that encourages individuals to develop a physically active lifestyle, to enhance their health and well-being.

Physical education is taught within the school curriculum (in most countries) and/or in preschools, colleges and universities, military institutions, and sports clubs.

The role of physical education goes beyond exercise. Indeed, developing skills, attitudes, and cooperation are key elements in this program.

The following are the importance of physical education.

1. Assist Students In Reaching Their Physical Potential In a Variety of Sporting Environments

Physical education assists students in reaching their physical potential by supporting training within a variety of sporting environments. Benefits include improved kinesthetic learning and socialization with peers, teachers, and coaches.

This important course is made even more enjoyable when good teachers are at hand to not only educate but inspire others to reach their full potential in a variety of sporting environments.

Physical education also prepares the body for participation in a wide range of sports, recreational activities, and other endeavors. It is an excellent example of a core curriculum in school systems.

2. Provides Opportunities for Kids To Take Responsibility for Their Health

Physical education is important for kids to play and stay healthy throughout their lives. It can provide opportunities for kids to take responsibility for their health . Kids learn about food choices, exercise, diet and nutrition, and personal fitness through physical education.

A number of studies have shown that children who are physically fit are less likely to suffer from health problems and tend to live much longer than their less active counterparts. With regular physical activity, the overall health of a child can be dramatically improved.

3. Serves as an Outlet for Stress

Physical education is important because it offers students/children an outlet for stress due to all of the academic pressures. When kids participate in physical education and sports, they learn to be part of a team, how to persevere when they fail, and they learn the value of cooperation.

Having to perform physical activity can reduce the stress in a person’s body. For example, many types of exercise will produce endorphins in the body. The feeling of the body releasing its hormones will make the person feel happy and relaxed.

4. Improves Mental Health

There is long-standing research showing that physical activity improves mental health and well-being. The importance of physical education courses to a student’s overall well-being cannot be overstated.

With these kinds of classes, teachers are able to establish the proper balance between physical and mental training for the students in their care. A physically active lifestyle actively contributes to the health and well-being of a person.

Physical education encourages a healthy diet, which reduces fatigue and stress throughout the day, as well as helps reduce body fat. It also eliminates the problems of obesity and poor eating habits that add stress to the body and mind instead of alleviating it.

Children who participate in sports have higher levels of self-esteem and are less prone to develop learning disorders. They also have fewer health problems than their non-athletic peers. In addition, a child’s IQ increases when he participates in sports.

5. Improves Attention Span, Self-Esteem, and Body Image

One of the most important reasons for physical education is that it has been proven to improve a whole range of skills, from increasing attention span to improving self-esteem, and from enhancing body image to helping develop social skills.

Physical activity also has a positive effect on body image by building muscle tone and bone mass, allowing you to feel good about how you look. Getting an adequate amount of physical activity helps you sleep better at night and reduces anxiety.

In addition, regular physical activity improves your emotional well-being, which is an important aspect of physical education.

6. Nourishes Friendships – Peers and Teachers

Physical education nourishes social relationships. Students need to have positive social relationships with their teachers and peers to learn. In a classroom setting, it gives students the chance to bond with their classmates.

This is particularly helpful in middle school and high school. The teachers are often involved in extracurricular activities, such as leading the football team to victory or making sure everyone makes it to softball practice. These activities cultivate relationships between teachers and students.

7. Builds Self-Confidence and Self-Reliance

P.E classes are not just about theory, they are also an opportunity for children to get some exercise. Active physical activity can help boost a student’s confidence, as well as provide opportunities to learn how to make decisions on the field.

Furthermore, regardless of gender, age, race, or physical ability; those who participate in a well-rounded PE program will notice numerous benefits to their level of confidence and independence.

8. To Enhance Leadership Skills, Teamwork, and Sportsmanship

Physical education is important to help youths in becoming physically fit. It enhances one’s self-discipline, teamwork, leadership skills, and sportsmanship. For example, it can be seen in the difference between elite athletes and non-elite athletes.

This program helps students develop self-discipline through time management, planning for success, and stepping out of their comfort zones to learn new things they are uncomfortable with. It also encourages them to develop a good sense of self-esteem, and it teaches them to be fair and accept criticism.

9. Physical Education Lessons Can Help You Get into College

Everybody knows that physical education lessons are great for developing your mind, body, and soul.

Did you know, however, that as well as developing fitness, PE lessons can also help you get into college and increase your chances of getting the grades you want?

Let’s face it, physical education isn’t at the top of everyone’s favorite subject list. However, if you’re a high school student trying to get into college, you might want to think about P.E lessons as your new best friend.

If you are on a sports team, these lessons can help you get into college. Through the physical education program, you can participate in one or more sports such as football, soccer, basketball, and volleyball.

There is a wide range of options for students to participate in trying different sports at their high school.

10. Sport Helps Children Develop Their Motor Skills and Strengthen Their Muscles

Physical education is something that teachers, students, and parents really should think about. It is one of the most important things in a child’s life.

Some people say that it is only to teach children how to play games or sports. But this is not true. P.E is used to do much more than teach children how to play sports.

Physical education helps kids develop their motor skills and strengthen their muscles. When children have a variety of experiences with basic physical activities, they are more likely to enjoy sports and movement as they get older. Poor motor development can lead to physical problems and difficulty with schoolwork later in life.

What Role Does the Teacher Play in Physical Education Classes?

In the present day, physical education is a subject that is taken very seriously by many educational institutions around the world.

In fact, it has now become one of the required subjects in public schools. It is an important component of a child’s education.

It provides important skills that children need to succeed and progress in many other areas of life. P.E can provide the foundation for learning and development.

As a teacher, your role is to ensure that you cover all of the necessary learning objectives. You should also maintain a balance between individual, group, and team activities throughout the unit.

Physical education teachers are professional educators devoted to teaching students the importance of a healthy body and mind. They teach students the basics of different sports and games, as well as how to enjoy being active.

Who needs physical education?

Everyone needs physical education. You may be a workaholic or a college student or possess the physique of a world-class athlete, but one thing is certain – you need physical education to be fit and healthy. Keeping fit can help you ward off serious diseases and improve your quality of life.

How can teachers and school administrators encourage students to participate in sports?

Schools and teachers can promote physical education by helping to reduce the cost of equipment and uniforms, offering time after school for sports, and organizing team activities during lunchtime.

Another way is to get everyone to participate. The more people are aware of the benefits of physical education, the more likely students will be to participate.

For example, schools can organize intramural teams, or arrange for sports games outside of school hours.

A well-designed PE program will give students the opportunity to participate in a variety of activities, improve their physical fitness and coordination, develop social skills, and learn lifelong sportsmanship.

How can you encourage your child to play sports for his or her health if you don’t know anything about sports?

A lot of parents who don’t play sports often have a hard time convincing their kids that they need to exercise. That’s because they don’t understand why their kids should be getting up off the couch and staying active.

You don’t have to be a sports expert to encourage your child’s love of sports. As the parent of an athlete, your role is very important—you can provide support and guidance.

Encourage your child by joining the fun, not just watching from the sidelines. Stay positive, supportive, and encouraging.

Is physical education for children alone?

No, physical education is not just for children alone. Today, adults also worry about their health and wellness. It is important for children to engage in physical activity daily.

The benefits are endless. Both the old and young will learn overall body control, enhance motor skills and coordination, and build strength.

Besides, it is actually more important for adults to have an activity that moves their body than to sit in front of computers all day. It is even more important if they are going to work out to get good work physical exercise that can potentially be life-saving.

Final Thoughts

Physical education has numerous impacts on our lives. It has a big role to play in ensuring that we are healthy, helping to prevent both mental and physical illness. It also has an important role to play in the development of our lifestyles and the way we feel about ourselves.

As a result of participating in physical education programs, students prepare themselves for a physically and mentally healthy life. They will also learn new skills and activities that will enrich their lives outside of school.

Education is important , but there is no denying the positive effects that physical fitness can have on the mind.

If you are an individual seeking information or a school seeking a solution, you’ll find inspiration, guidance, and valuable resources on LMS Hero .

By reading the educational articles, you can find fresh ideas on LMS Hero that can help you make measurable improvements in the education sector.

Thanks for reading.

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Committee on Physical Activity and Physical Education in the School Environment; Food and Nutrition Board; Institute of Medicine; Kohl HW III, Cook HD, editors. Educating the Student Body: Taking Physical Activity and Physical Education to School. Washington (DC): National Academies Press (US); 2013 Oct 30.

Educating the Student Body: Taking Physical Activity and Physical Education to School.

Hardcopy Version at National Academies Press

3 Physical Activity and Physical Education: Relationship to Growth, Development, and Health

Key messages.

Regular physical activity promotes growth and development and has multiple benefits for physical, mental, and psychosocial health that undoubtedly contribute to learning.
Specifically, physical activity reduces the risk for heart disease, diabetes mellitus, osteoporosis, high blood pressure, obesity, and metabolic syndrome; improves various other aspects of health and fitness, including aerobic capacity, muscle and bone strength, flexibility, insulin sensitivity, and lipid profiles; and reduces stress, anxiety, and depression.
Physical activity can improve mental health by decreasing and preventing conditions such as anxiety and depression, as well as improving mood and other aspects of well-being.
Physical activity programming specifically designed to do so can improve psychosocial outcomes such as self-concept, social behaviors, goal orientation, and most notably self-efficacy. These attributes in turn are important determinants of current and future participation in physical activity.
Sedentary behaviors such as sitting and television viewing contribute to health risks both because of and independently of their impact on physical activity.
Health-related behaviors and disease risk factors track from childhood to adulthood, indicating that early and ongoing opportunities for physical activity are needed for maximum health benefit.
To be effective, physical activity programming must align with the predictable developmental changes in children's exercise capacity and motor skills, which affect the activities in which they can successfully engage.
Frequent bouts of physical activity throughout the day yield short-term benefits for mental and cognitive health while also providing opportunities to practice skills and building confidence that promotes ongoing engagement in physical activity.
Distinct types of physical activity address unique health concerns and contribute in distinct ways to children's health, suggesting that a varied regimen including aerobic and resistance exercise, structured and unstructured opportunities, and both longer sessions and shorter bouts will likely confer the greatest benefit.

The behaviors and traits of today's children, along with their genetics, are determinants of their growth and development; their physical, mental, and psychosocial health; and their physical, cognitive, and academic performance. Technological advances of modern society have contributed to a sedentary lifestyle that has changed the phenotype of children from that of 20 years ago. Children today weigh more and have a higher body mass index (BMI) than their peers of just a generation earlier ( Ogden et al., 2012 ). Behaviorally, most children fail to engage in vigorous- or moderate-intensity physical activity for the recommended 60 minutes or more each day, with as many as one-third reporting no physical activity in the preceding 5 days ( CDC, 2012 ). This lack of participation in physical activity has contributed to a greater prevalence of pediatric obesity, a decrease in fitness (e.g., flexibility, muscular strength, cardiorespiratory capacity), and a greater risk for disease ( Boreham and Riddoch, 2001 ; Eisenmann, 2003 ; Malina, 2007 ; Steele et al., 2008 ). (See Box 3-1 for an overview of the relationship between physical activity and physical fitness.)

Physical Activity and Physical Fitness. As noted in Chapter 1 (see the box titled “Key Terms Used in This Report” on p. 17), physical activity, a behavior, is defined as bodily movement that increases energy expenditure, whereas fitness (more...)

While more can always be learned, the evidence for the health benefits of physical activity is irrefutable ( HHS, 1996 , 2008 ). Adults engaged in regular physical activity have lower rates of chronic disease (e.g., coronary heart disease, cardiovascular disease, type 2 diabetes, hypertension, osteoporosis, and some cancers) and are less likely to die prematurely ( HHS, 1996 , 2008 ; Bauman, 2004 ). And while the ill effects of chronic disease are manifested mainly in adults, it is increasingly better understood that the development of these conditions starts in childhood and adolescence ( Hallal et al., 2006 ; Cook et al., 2009 ; Halfon et al., 2012 ). It appears evident, then, that promotion of health-enhancing behaviors must also start early in life. Indeed, growing evidence points to long-term effects of child and adolescent physical activity on adult morbidity and mortality in addition to its more immediate effects ( Hallal et al., 2006 ) (see Figure 3-1 ).

Conceptual model of how physical activity in childhood and adolescence is beneficial to health. Physical activity has both immediate and long-term health benefits: (a) Physical activity tends to track; early physical activity is associated with physical (more...)

Evidence for both direct and indirect health effects of physical activity has been reported ( Hallal et al., 2006 ), and the need for ongoing participation in physical activity to stimulate and maintain the chronic adaptations that underlie those benefits is well documented. To understand the relationship of physical activity and aerobic fitness to health during childhood, it is important first to recognize the developmental changes that occur throughout maturation. During the early stages of adolescence, for example, participation in physical activity and corresponding physical fitness begin to decline ( Duncan et al., 2007 ). Such differences across stages of development highlight the importance of examining the effects of growth and maturation on physical and cognitive health. Accordingly, this chapter reviews how physical activity may influence developmental processes and other aspects of somatic growth and maturation. A complete review of the effects of physical activity on all tissues and systems is beyond the scope of this report. Rather, the focus is on components of body composition and systems that underlie engagement in physical activity, physical fitness, and chronic disease risk and that in turn influence other aspects of health and academic performance (discussed in Chapter 4 ). Addressed in turn is the relationship between physical activity and physical, psychosocial, and mental health. Structural and functional brain maturation and how physical activity may influence those developmental processes and cognitive health are also reviewed in Chapter 4 .

PHYSICAL HEALTH

This section reviews what is known about the relationship between physical activity and (1) somatic growth, development, and function and (2) health- and performance-related fitness.

Somatic Growth, Development, and Function

Growth, Development, and Maturation. Growth is the normal process of increase in size as a result of accretion of tissues characteristic of the organism; growth is the dominant biological activity for most of the first two decades of life. Changes in (more...)

Developmental Stages

Postnatal growth is commonly divided into three or four age periods. Infancy spans the first year of life. Childhood extends from the end of infancy to the start of adolescence and is often divided into early childhood, which includes the preschool years, and middle childhood, which includes the elementary school years, into the 5th or 6th grade. Adolescence is more difficult to define because of variation in its onset and termination, although it is commonly defined as between 10 and 18 years of age ( WHO, 1986 ). The rapid growth and development of infancy continue during early childhood, although at a decelerating rate, whereas middle childhood is a period of slower, steady growth and maturation. Differences between boys and girls are relatively small until adolescence, which is marked by accelerated growth and attainment of sexual maturity ( Tanner, 1962 ).

Physically active and inactive children progress through identical stages. Providing opportunities for young children to be physically active is important not to affect the stages but to ensure adequate opportunity for skill development. Sound physical education curricula are based on an understanding of growth patterns and developmental stages and are critical to provide appropriate movement experiences that promote motor skill development ( Clark, 2005 ). The mastery of fundamental motor skills is strongly related to physical activity in children and adolescents ( Lubans et al., 2010 ) and in turn may contribute to physical, social, and cognitive development. Mastering fundamental motor skills also is critical to fostering physical activity because these skills serve as the foundation for more advanced and sport-specific movement ( Clark and Metcalfe, 2002 ; Hands et al., 2009 ; Robinson and Goodway, 2009 ; Lubans et al., 2010 ). Physical activity programs, such as physical education, should be based on developmentally appropriate motor activities to foster self-efficacy and enjoyment and encourage ongoing participation in physical activity.

Biological Maturation

Maturation is the process of attaining the fully adult state. In growth studies, maturity is typically assessed as skeletal, somatic, or sexual. The same hormones regulate skeletal, somatic, and sexual maturation during adolescence, so it is reasonable to expect the effect of physical activity on these indicators of maturity to be similar. Skeletal maturity is typically assessed from radiographs of the bones in the hand and wrist; it is not influenced by habitual physical activity. Similarly, age at peak height velocity (the most rapid change in height), an indicator of somatic maturity, is not affected by physical activity, nor is the magnitude of peak height velocity, which is well within the usual range in both active and inactive youth. Discussions of the effects of physical activity on sexual maturation more often focus on females than males and, in particular, on age at menarche (first menses). While some data suggest an association between later menarche and habitual physical activity ( Merzenich et al., 1993 ), most of these data come from retrospective studies of athletes ( Clapp and Little, 1995 ). Whether regular sports training at young ages before menarche “delays” menarche (later average age of menarche) remains unclear. While menarche occurs later in females who participate in some sports, the available data do not support a causal relationship between habitual physical activity and later menarche.

Puberty is the developmental period that represents the beginning of sexual maturation. It is marked by the appearance of secondary sex characteristics and their underlying hormonal changes, with accompanying sex differences in linear growth and body mass and composition. The timing of puberty varies, beginning as early as age 8 in girls and age 9 in boys in the United States and as late as ages 13-15 ( NRC/IOM, 1999 ). Recent research suggests that the onset of puberty is occurring earlier in girls today compared with the previous generation, and there is speculation that increased adiposity may be a cause ( Bau et al., 2009 ; Rosenfield et al., 2009 ). Conversely, some data suggest that excess adiposity in boys contributes to delayed sexual maturation ( Lee et al., 2010 ). Pubescence, the earliest period of adolescence, generally occurs about 2 years in advance of sexual maturity. Typically, individuals are in the secondary school years during this period, which is a time of decline in habitual physical activity, especially in girls. Physical activity trends are influenced by the development of secondary sex characteristics and other physical changes that occur during the adolescent growth spurt, as well as by societal and cultural factors. Research suggests that physical inactivity during adolescence carries over into adulthood ( Malina, 2001a , b ; CDC, 2006 ).

Adolescence is the transitional period between childhood and adulthood. The adolescent growth spurt, roughly 3 years of rapid growth, occurs early in this period. An accelerated increase in stature is a hallmark, with about 20 percent of adult stature being attained during this period. Along with the rapid increase in height, other changes in body proportions occur that have important implications for sports and other types of activities offered in physical education and physical activity programs. As boys and girls advance through puberty, for example, biacromial breadth (shoulder width) increases more in boys than in girls, while increases in bicristal breadth (hip width) are quite similar. Consequently, hip-shoulder width ratio, which is similar in boys and girls during childhood, decreases in adolescent boys while remaining relatively constant in girls ( Malina et al., 2004 ). Ratios among leg length, trunk length, and stature also change during this period. Prior to adolescence, boys have longer trunks and shorter legs than girls ( Haubenstricker and Sapp, 1980 ). In contrast, adolescent and adult females have shorter legs for the same height than males of equal stature. Body proportions, particularly skeletal dimensions, are unlikely to be influenced by physical activity; rather, body proportions influence performance success, fitness evaluation, and the types of activities in which a person may wish to engage. For example, there is evidence that leg length influences upright balance and speed ( Haubenstricker and Sapp, 1980 ). Individuals who have shorter legs and broader pelvises are better at balancing tasks than those with longer legs and narrower pelvises, and longer legs are associated with faster running times ( Dintiman et al., 1997 ). Also, longer arms and wider shoulders are advantageous in throwing tasks ( Haubenstricker and Sapp, 1980 ), as well as in other activities in which the arms are used as levers. According to Haubenstricker and Sapp (1980) , approximately 25 percent of engagement in movement-related activities can be attributed to body size and structure.

Motor Development

Motor development depends on the interaction of experience (e.g., practice, instruction, appropriate equipment) with an individual's physical, cognitive, and psychosocial status and proceeds in a predictable fashion across developmental periods. Clark and Metcalfe (2002) provide an eloquent metaphor—“the mountain of motor development”—to aid in understanding the global changes seen in movement across the life span. Early movements, critical for an infant's survival, are reflexive and dominated by biology, although environment contributes and helps shape reflexes. This initial reflexive period is followed quickly by the preadapted period , which begins when an infant's movement behaviors are no longer reflexive and ends when the infant begins to apply basic movement skills (e.g., crawling, rolling, standing, and walking) that generally are accomplished before 12 months of age. The period of fundamental motor patterns occurs approximately between the ages of 1 and 7 years, when children begin to acquire basic fundamental movement skills (e.g., running, hopping, skipping, jumping, leaping, sliding, galloping, throwing, catching, kicking, dribbling, and striking). Practice and instruction are key to learning these skills, and a great deal of time in elementary school physical education is devoted to exploration of movement. Around age 7, during the so-called context-specific period of motor development, children begin to refine basic motor skills and combine them into more specific movement patterns, ultimately reaching what has been called skillfulness . Compensation , the final period of motor development, occurs at varying points across the life span when, as a result of aging, disease, injury, or other changes, it becomes necessary to modify movement.

While all children need not be “expert” in all movement skills, those who do not acquire the fundamental motor skills will likely experience difficulty in transitioning their movement repertoire into specific contexts and engagement in physical activity ( Fisher et al., 2005 ; Barnett et al., 2009 ; Cliff et al., 2009 ; Robinson et al., 2012 ). A full movement repertoire is needed to engage in physical activities within and outside of the school setting. Thus, beyond contributing to levels of physical activity, physical education programs should aim to teach basic fundamental motor skills and their application to games, sports, and other physical activities, especially during the elementary years (i.e., the fundamental motor patterns and context-specific periods). At the same time, it is important to be mindful of the wide interindividual variation in the rate at which children develop motor skills, which is determined by their biological makeup, their rate of physical maturation, the extent and quality of their movement experiences, and their family and community environment.

An increasing amount of evidence suggests that people who feel competent in performing physical skills remain more active throughout their lives ( Lubans et al., 2010 ). Conversely, those who are less skilled may be hesitant to display what they perceive as a shortcoming and so may opt out of activities requiring higher levels of motor competence ( Stodden et al., 2008 ). Children who are less physically skillful tend to be less active than their skillful counterparts ( Wrotniak et al., 2006 ; Williams et al., 2008 ; Robinson et al., 2012 ) and thus have a greater risk of overweight and obesity ( Graf et al., 2004 ). Fundamental skills are the building blocks of more complex actions that are completed in sports, physical activities, and exercise settings. For example, throwing is a fundamental skill that is incorporated into the context-specific throw used in activities such as handball, softball, and water polo. Fundamental skills are of primary interest to both physical education teachers and coaches, and physical education classes should be designed to challenge learners to develop their motor skills.

In 1998 the Centers for Disease Control and Prevention's (CDC's) Division of Nutrition and Physical Activity organized a workshop to determine future directions for research on physical activity. The workshop convened 21 experts from a wide range of academic disciplines. One recommendation resulting from the proceedings was for future research to describe the temporal relationship between motor development and physical activity ( Fulton et al., 2001 ), signifying the importance of better understanding of the nature of the relationship between motor competence and physical activity. The assumption of this relationship is implied in multiple models of motor development ( Seefeldt, 1980 ; Clark and Metcalfe, 2002 ; Stodden et al., 2008 ), which emphasize the importance of motor competence as a prerequisite for engagement in physical activity throughout the life span.

Two models that are commonly used to examine this relationship are Seefeldt's (1980) hierarchical order of motor skills development and the dynamic association model of Stodden and colleagues (2008) . Seefeldt proposed a hierarchical order of motor skills development that includes four levels: reflexes, fundamental motor skills, transitional motor skills (i.e., fundamental motor skills that are performed in various combinations and with variations and that are required to participate in entry-level organized sports, such as throwing for distance, throwing for accuracy, and/or catching a ball while in motion), and specific sports skills and dances. With improved transitional motor skills, children are able to master complex motor skills (e.g., those required for playing more complex sports such as football or basketball). At the end of this developmental period, children's vision is fully mature. The progression through each level occurs through developmental stages as a combined result of growth, maturation, and experience. Seefeldt hypothesized the existence of a “proficiency barrier” between the fundamental and transitional levels of motor skills development. If children are able to achieve a level of competence above the proficiency barrier, they are more likely to continue to engage in physical activity throughout the life span that requires the use of fundamental motor skills. Conversely, less skilled children who do not exceed the proficiency barrier will be less likely to continue to engage in physical activity. Thus, it is assumed that “a confident and competent mover will be an active mover” ( Clark, 2005 , p. 44). For example, to engage successfully in a game of handball, baseball, cricket, or basketball at any age, it is important to reach a minimum level of competence in running, throwing, catching, and striking. The assumption of the existence of a relationship between motor competence and physical activity is at the “heart of our physical education programs” ( Clark, 2005 , p. 44). A thorough understanding of how this relationship changes across developmental stages is crucial for curriculum development and delivery and teaching practices.

Lubans and colleagues (2010) recently examined the relationship between motor competence and health outcomes. They reviewed 21 studies identifying relationships between fundamental motor skills and self-worth, perceived physical competence, muscular and cardiorespiratory fitness, weight status, flexibility, physical activity, and sedentary behavior. Overall, the studies found a positive association between fundamental motor skills and physical activity in children and adolescents, as well as a positive relationship between fundamental motor skills and cardiorespiratory fitness. Other research findings support the hypothesis that the most physically active preschool-age ( Fisher et al., 2005 ; Williams et al., 2008 ; Robinson et al., 2012 ), elementary school–age ( Bouffard et al., 1996 ; Graf et al., 2004 ; Wrotniak et al., 2006 ; Hume et al., 2008 ; Lopes et al., 2011 ), and adolescent ( Okely et al., 2001 ) youth are also the most skilled.

An advantage of the “proficiency barrier” hypothesis proposed by Seefeldt (1980) is its recognition that the relationship between motor competence and physical activity may not be linear. Rather, the hypothesis suggests that physical activity is influenced when a certain level of motor competence is not achieved and acknowledges that below the proficiency barrier, there is bound to be substantial variation in children's motor competence and participation in physical activity. The proficiency barrier is located between the fundamental and transitional motor skills periods. The transition between these two levels of motor competence is expected to occur between the early and middle childhood years. Stodden and colleagues (2008) suggest that the relationship between motor competence and physical activity is dynamic and changes across time. In their model the “development of motor skill competence is a primary underlying mechanism that promotes engagement in physical activity” (p. 290).

The relationship between skills and physical activity is considered reciprocal. It is expected that as motor skills competence increases, physical activity participation also increases and that the increased participation feeds back into motor skills competence. The reciprocal relationship between motor skills competence and physical activity is weak during the early childhood years (ages 2-8) because of a variety of factors, including environmental conditions, parental influences, and previous experience in physical education programs ( Stodden et al., 2008 ). Also, children at this age are less able to distinguish accurately between perceived physical competence and actual motor skills competence ( Harter and Pike, 1984 ; Goodway and Rudisill, 1997 ; Robinson and Goodway, 2009 ; Robinson, 2011 ), and thus motor skills are not expected to strongly influence physical activity. The literature supports this hypothesis, as indicated by low to moderate correlations between motor skills competence and physical activity in preschool ( Sääkslahti et al., 1999 ; Williams et al., 2008 ; Cliff et al., 2009 ; Robinson and Goodway, 2009 ; Robinson, 2011 ) and early elementary school–age ( Raudsepp and Päll, 2006 ; Hume et al., 2008 ; Morgan et al., 2008 ; Houwen et al., 2009 ; Ziviani et al., 2009 ; Lopes et al., 2011 ) children.

In older children, perceived competence is more closely related to actual motor skills competence. Older, low-skilled children are aware of their skills level and are more likely to perceive physical activity as difficult and challenging. Older children who are not equipped with the necessary skills to engage in physical activity that requires high levels of motor skills competence may not want to display their low competence publicly. As children transition into adolescence and early adulthood, the relationship between motor skills competence and physical activity may strengthen ( Stodden et al., 2008 ). Investigators report moderate correlations between motor skills competence and physical activity in middle school–age children ( Reed et al., 2004 ; Jaakkola et al., 2009 ). Okely and colleagues (2001) found that motor skills competence was significantly associated with participation in organized physical activity (i.e., regular and structured experiences related to physical activity) as measured by self-reports. A strength of the model of Stodden and colleagues (2008) is the inclusion of factors related to psychosocial health and development that may influence the relationship between motor skills competence and physical activity, contributing to the development and maintenance of obesity. Other studies have found that perceived competence plays a role in engagement in physical activity ( Ferrer-Caja and Weiss, 2000 ; Sollerhed et al., 2008 ).

Motor skills competence is an important factor; however, it is only one of many factors that contribute to physical activity. For instance, three studies have reported negative correlations between girls' motor competence and physical activity ( Reed et al., 2004 ; Cliff et al., 2009 ; Ziviani et al., 2009 ), suggesting that sex may be another determining factor. A possible explanation for these findings is that since girls tend to be less active than boys, it may be more difficult to detect differences in physical activity levels between high- and low-skilled girls. It is also possible that out-of-school opportunities for physical activity are more likely to meet the interests of boys, which may at least partially explain sex differences in physical activity levels ( Le Masurier et al., 2005 ). Previous research suggests that in general boys are more motor competent than girls ( Graf et al., 2004 ; Barnett et al., 2009 ; Lopes et al., 2011 ) and that this trend, which is less apparent in early childhood, increases through adolescence ( Thomas and French, 1985 ; Thomas and Thomas, 1988 ; Thomas, 1994 ), although one study reports that girls are more motor competent than boys ( Cliff et al., 2009 ).

One component of motor competence is the performance of gross motor skills, which are typically classified into object control and locomotor skills. Consistent evidence suggests that boys are more competent in object control skills, while girls are more competent in locomotor skills ( McKenzie et al., 2004 ; Morgan et al., 2008 ; Barnett et al., 2009 ). In light of these sex differences, it is important to examine the relationships of object control and locomotor skills with physical activity separately for boys and girls. For boys, object control skills are more related to physical activity than are locomotor skills ( Hume et al., 2008 ; Morgan et al., 2008 ; Williams et al., 2008 ; Cliff et al., 2009 ), whereas evidence suggests that the reverse is true for girls ( McKenzie et al., 2002 ; Hume et al., 2008 ; Cliff et al., 2009 ; Jaakkola et al., 2009 ). Three studies report a significant relationship between balance and physical activity for girls but not boys ( Reed et al., 2004 ; Ziviani et al., 2009 ). Cliff and colleagues (2009) suggest that object control and locomotor skills may be more related to boys' and girls' physical activity, respectively, because of the activity type in which each sex typically engages.

The relationship between motor competence and physical activity clearly is complex. It is quite likely that the relationship is dynamic and that motor competence increases the likelihood of participating in physical activity while at the same time engaging in physical activity provides opportunities to develop motor competence ( Stodden et al., 2008 ). Despite some uncertainty, the literature does reinforce the important role of physical education in providing developmentally appropriate movement opportunities in the school environment. These opportunities are the only means of engaging a large population of children and youth and providing them with the tools and opportunities that foster health, development, and future physical activity.

Regular physical activity has no established effect on linear growth rate or ultimate height ( Malina, 1994 ). Although some studies suggest small differences, factors other than physical activity, especially maturity, often are not well controlled. It is important to note that regular physical activity does not have a negative effect on stature, as has sometimes been suggested. Differences in height among children and adolescents participating in various sports are more likely due to the requirements of the sport, selection criteria, and interindividual variation in biological maturity than the effects of participation per se ( Malina et al., 2004 ).

Body Weight

Although physical activity is inversely related to weight, correlations are generally low (~r–0.15), and differences in body weight between active and inactive boys and girls tend to be small ( Mirwald and Bailey, 1986 ; Saris et al., 1986 ; Beunen et al., 1992 ; Lohman et al., 2006 ;), except in very obese children and adolescents. Similarly, physique, as represented in somatotypes, does not appear to be significantly affected by physical activity during growth ( Malina et al., 2004 ). In contrast, components of weight can be influenced by regular physical activity, especially when the mode and intensity of the activity are tailored to the desired outcome. Much of the available data in children and adolescents is based on BMI, a surrogate for composition, and indirect methods based on the two-compartment model of body composition in which body weight is divided into its fat-free and fat components ( Going et al., 2012 ). While studies generally support that physical activity is associated with greater fat-free mass and lower body fat, distinguishing the effects of physical activity on fat-free mass from expected changes associated with growth and maturation is difficult, especially during adolescence, when both sexes have significant growth in fat-free mass. The application of methods based on the two-compartment model is fraught with errors, especially when the goal is to detect changes in fat-free mass, and no information is available from these methods regarding changes in the major tissue components of fat-free mass—muscle and skeletal tissue.

Skeletal muscle is the largest tissue mass in the body. It is the main energy-consuming tissue and provides the propulsive force for movement. Muscle represents about 23-25 percent of body weight at birth and about 40 percent in adults, although there is a wide range of “normal” ( Malina, 1986 , 1996 ). Postnatal muscle growth is explained largely by increases in cell size (hypertrophy) driving an increase in overall muscle mass. The increase in muscle mass with age is fairly linear from young childhood until puberty, with boys having a small but consistent advantage ( Malina, 1969 , 1986 ). The sex difference becomes magnified during and after puberty, driven primarily by gender-related differences in sex steroids. Muscle, as a percentage of body mass, increases from about 42 percent to 54 percent in boys between ages 5 and 11, whereas in girls it increases from about 40 percent to 45 percent between ages 5 and 13 and thereafter declines ( Malina et al., 2004 ). It should be noted that absolute mass does not decline; rather, the relative decline reflects the increase in the percentage of weight that is fat in girls. At least part of the sex difference is due to differences in muscle development for different body regions ( Tanner et al., 1981 ). The growth rate of arm muscle tissue during adolescence in males is approximately twice that in females, whereas the sex difference in the growth of muscle tissue in the leg is much smaller. The sex difference that develops during puberty persists into adulthood and is more apparent for the musculature of the upper extremities.

Sex-related differences in muscular development contribute to differences in physical performance. Muscle strength develops in proportion to the cross-sectional area of muscle, and growth curves for strength are essentially the same as those for muscle ( Malina and Roche, 1983 ). Thus the sex difference in muscle strength is explained largely by differences in skeletal muscle mass rather than muscle quality or composition. Aerobic (endurance) exercise has little effect on enhancing muscle mass but does result in significant improvement in oxygen extraction and aerobic metabolism ( Fournier et al., 1982 ). In contrast, numerous studies have shown that high-intensity resistance exercise induces muscle hypertrophy, with associated increases in muscle strength. In children and adolescents, strength training can increase muscle strength, power, and endurance. Multiple types of resistance training modalities have proven effective and safe ( Bernhardt et al., 2001 ), and resistance exercise is now recommended for enhancing physical health and function ( Behringer et al., 2010 ). These adaptations are due to muscle fiber hypertrophy and neural adaptations, with muscle hypertrophy playing a more important role in adolescents, especially in males. Prior to puberty, before the increase in anabolic sex steroid concentrations, neural adaptations explain much of the improvement in muscle function with exercise in both boys and girls.

The skeleton is the permanent supportive framework of the body. It provides protection for vital organs and is the main mineral reservoir. Bone tissue constitutes most of the skeleton, accounting for 14-17 percent of body weight across the life span ( Trotter and Peterson, 1970 ; Trotter and Hixon, 1974 ). Skeletal strength, which dictates fracture risk, is determined by both the material and structural properties of bone, both of which are dependent on mineral accrual. The relative mineral content of bone does not differ much among infants, children, adolescents, and adults, making up 63-65 percent of the dry, fat-free weight of the skeleton ( Malina, 1996 ). As a fraction of weight, bone mineral (the ash weight of bone) represents about 2 percent of body weight in infants and about 4-5 percent of body weight in adults ( Malina, 1996 ). Bone mineral content increases fairly linearly with age, with no sex difference during childhood. Girls have, on average, a slightly greater bone mineral content than boys in early adolescence, reflecting their earlier adolescent growth spurt. Boys have their growth spurt later than girls, and their bone mineral content continues to increase through late adolescence, ending with greater skeletal dimensions and bone mineral content ( Mølgaard et al., 1997 ). The increase in total body bone mineral is explained by both increases in skeletal length and width and a small increase in bone mineral density ( Malina et al., 2004 ).

Many studies have shown a positive effect of physical activity on intermediate markers of bone health, such as bone mineral content and density. Active children and adolescents have greater bone mineral content and density than their less active peers, even after controlling for differences in height and muscle mass ( Wang et al., 2004 ; Hind and Burrows, 2007 ; Tobias et al., 2007 ). Exercise interventions support the findings from observational studies showing beneficial effects on bone mineral content and density in exercise participants versus controls ( Petit et al., 2002 ; Specker and Binkley, 2003 ), although the benefit is less than is suggested by cross-sectional studies comparing active versus inactive individuals ( Bloomfield et al., 2004 ). The relationship between greater bone mineral density and bone strength is unclear, as bone strength cannot be measured directly in humans. Thus, whether the effects of physical activity on bone mineral density translate into similar benefits for fracture risk is uncertain ( Karlsson, 2007 ). Animal studies have shown that loading causes small changes in bone mineral content and bone mineral density that result in large increases in bone strength, supporting the notion that physical activity probably affects the skeleton in a way that results in important gains in bone strength ( Umemura et al., 1997 ). The relatively recent application of peripheral quantitative computed tomography for estimating bone strength in youth has also provided some results suggesting an increase in bone strength with greater than usual physical activity ( Sardinha et al., 2008 ; Farr et al., 2011 ).

The intensity of exercise appears to be a key determinant of the osteogenic response ( Turner and Robling, 2003 ). Bone tissue, like other tissues, accommodates to usual daily activities. Thus, activities such as walking have a modest effect at best, since even relatively inactive individuals take many steps (>1,000) per day. Activities generating greater muscle force on bone, such as resistance exercise, and “impact” activities with greater than ordinary ground reaction forces (e.g., hopping, skipping, jumping, gymnastics) promote increased mineralization and modeling ( Bloomfield et al., 2004 ; Farr et al., 2011 ). Far fewer randomized controlled trials (RCTs) examining this relationship have been conducted in children than in adults, and there is little evidence on dose response to show how the type of exercise interacts with frequency, intensity, and duration. Taken together, however, the available evidence supports beneficial effects of physical activity in promoting bone development ( Bailey et al., 1996 ; Modlesky and Lewis, 2002 ).

Physical activity may reduce osteoporosis-related fracture risk by increasing bone mineral accrual during development; by enhancing bone strength; and by reducing the risk of falls by improving muscle strength, flexibility, coordination, and balance ( Bloomfield et al., 2004 ). Early puberty is a key developmental period. Approximately 26 percent of the mineral content in the adult skeleton is accrued during the 2 years around the time of peak height velocity ( Bailey et al., 2000 ). This amount of mineral accrual represents approximately the same amount of bone mineral that most people will lose in their entire adult lives ( Arlot et al., 1997 ). The increase in mineral contributes to increased bone strength. Mineral is accrued on the periosteal surface of bone, such that the bone grows wider. Increased bone width, independent of the increased mineral mass, also contributes to greater bone strength. Indeed, an increase of as little as 1 mm in the outer surface of bone increases strength substantially. Adding bone to the endosteal surface also increases strength ( Parfitt, 1994 ; Wang et al., 2009 ). Increases in testosterone may be a greater stimulus of periosteal expansion than estrogen since testosterone contributes to wider and stronger bones in males compared with females. Retrospective studies in tennis players and gymnasts suggest structural adaptations may persist many years later in adulthood and are greatest when “impact” activity is initiated in childhood ( Kannus et al., 1995 ; Bass et al., 1998 ). RCTs on this issue are few, although the available data are promising ( McKay et al., 2000 ; Fuchs et al., 2001 ; MacKelvie et al., 2001 , 2003 ; Lindén et al., 2006 ). Thus, impact exercise begun in childhood may result in lasting structural changes that may contribute to increased bone strength and decreased fracture risk later in life ( Turner and Robling, 2003 ; Ferrari et al., 2006 ).

Adipose tissue

The adipose “organ” is composed of fat cells known as adipocytes ( Ailhaud and Hauner, 1998 ). Adipocytes are distributed throughout the body in various organs and tissues, although they are largely clustered anatomically in structures called fat depots, which include a large number of adipocytes held together by a scaffold-like structure of collagen and other structural molecules. In the traditional view of the adipocyte, the cell provides a storage structure for fatty acids in the form of triacylglycerol molecules, with fatty acids being released when metabolic fuel is needed ( Arner and Eckel, 1998 ). While adipocytes play this critical role, they are also involved in a number of endocrine, autocrine, and paracrine actions and play a key role in regulating other tissues and biological functions, for example, immunity and blood pressure, energy balance, glucose and lipid metabolism, and energy demands of exercise ( Ailhaud and Hauner, 1998 ; Frühbeck et al., 2001 ). The role of adipocytes in regulation of energy balance and in carbohydrate and lipid metabolism and the potential effects of physical activity on adipocyte function are of particular interest here, given growing concerns related to pediatric and adult obesity ( Ogden et al., 2012 ) and the associated risk of cardiometabolic disease ( Weiss et al., 2004 ; Eisenmann, 2007 a,b; Steele et al., 2008 ). Metabolic differences among various fat depots are now well known ( Frühbeck et al., 2001 ), and there is significant interest in the distribution of adipose tissue, the changes that occur during childhood and adolescence, and their clinical significance.

Adipocytes increase in size (hypertrophy) and number (hyperplasia) from birth through childhood and adolescence and into young adulthood to accommodate energy storage needs. The number of adipocytes has been estimated to increase from about 5 billion at birth to 30 billion to 50 billion in the nonobese adult, with an increase in average diameter from about 30-40 μm at birth to about 80-100 μm in the young adult ( Knittle et al., 1979 ; Bonnet and Rocour-Brumioul, 1981 ; Chumlea et al., 1982 ). In total the adipose organ contains about 0.5 kg of adipocytes at birth in both males and females, increasing to approximately 10 kg in average-weight-for-height males and 14 kg in females ( Malina et al., 2004 ). There is wide interindividual variation, however, and the difficulty of investigating changes in the number and size of adipocytes is obvious given the invasiveness of the required biopsy procedures; understandably, then, data on these topics are scarce in children and adolescents. Also, since only subcutaneous depots are accessible, results must be extrapolated from a few sites.

Based on such information, the average size of adipocytes has been reported to increase two- to threefold in the first year of life, with little increase in nonobese boys and girls until puberty ( Malina et al., 2004 ). A small increase in average adipocyte size at puberty is more obvious in girls than in boys. There is considerable variation in size across various subcutaneous sites and between subcutaneous and internal depots. The number of adipocytes is difficult to estimate. Available data suggest that the cellularity of adipose tissue does not increase significantly in early postnatal life ( Malina et al., 2004 ). Thus, gain in fat mass is the result of an increase in the size of existing adipocytes. From about 1-2 years of age and continuing through early and middle childhood, the number of adipocytes increases gradually two- to threefold. With puberty the number practically doubles, followed by a plateau in late adolescence and early adulthood. The number of adipocytes is similar in boys and girls until puberty, when girls experience a greater increase than boys.

The increases in the number of adipocytes during infancy and puberty are considered critical for enlargement of the adipose tissue organ and for the risk of obesity. Since size and number are linked, the number of adipocytes can potentially increase at any age if fat storage mechanisms are stimulated by chronic energy surfeit ( Hager, 1981 ; Chumlea et al., 1982 ). Energy expenditure through regular physical activity is a critical element in preventing energy surfeit and excess adiposity. While cellularity undoubtedly is strongly genetically determined, regular physical activity, through its contribution to energy expenditure, can contribute to less adipocyte hyperplasia by limiting hypertrophy.

Fat distribution

Fat distribution refers to the location of fat depots on the body. The metabolic activities of fat depots differ, and small variation can have a long-term impact on fat distribution. Differences in metabolic properties across depots also have clinical implications. Visceral adipose tissue in the abdominal cavity is more metabolically active (reflected by free fatty acid flux) than adipose tissue in other areas ( Arner and Eckel, 1998 ), and higher amounts of visceral adipose tissue are associated with greater risk of metabolic complications, such as type 2 diabetes and cardiovascular disease ( Daniels et al., 1999 ; He et al., 2007 ; Dencker et al., 2012 ). In contrast, subcutaneous fat, particularly in the gluteofemoral region, is generally associated with a lower risk of cardiometabolic disease. Age- and sex-associated variations in fat distribution contribute to age- and sex-associated differences in cardiometabolic disease prevalence. Girls have more subcutaneous fat than boys at all ages, although relative fat distribution is similar. After a rapid rise in subcutaneous fat in the first few months of life, both sexes experience a reduction through age 6 or 7 ( Malina and Roche, 1983 ; Malina and Bouchard, 1988 ; Malina, 1996 ). Girls then show a linear increase in subcutaneous fat, whereas boys show a small increase between ages 7 and 12 or 13 and then an overall reduction during puberty. The thickness of subcutaneous fat on the trunk is approximately one-half that of subcutaneous fat on the extremities in both boys and girls during childhood. The ratio increases with age in males during adolescence but changes only slightly in girls. In males the increasing ratio of trunk to extremity subcutaneous fat is a consequence of slowly increasing trunk subcutaneous fat and a decrease in subcutaneous fat on the extremities. In girls, trunk and extremity subcutaneous fat increase at a similar rate; thus the ratio is stable ( Malina and Bouchard, 1988 ). As a consequence, the sex difference in the distribution of body fat develops during adolescence. It is important to note that changes in subcutaneous fat pattern do not necessarily represent changes in abdominal visceral adipose tissue.

Tracking of subcutaneous fat has been investigated based on skinfold thicknesses and radiographs of fat widths in males and females across a broad age range ( Katzmarzyk et al., 1999 ; Campbell et al., 2012 ). Results indicate that subcutaneous fat is labile during early childhood. After age 7 to 8, correlations between subcutaneous fat in later childhood and adolescence and adult subcutaneous fat are significant and moderate. Longitudinal data on tracking of visceral adipose tissue are not available, but percent body fat does appear to track. Thus children and especially adolescents with higher levels of body fat have a higher risk of being overfat at subsequent examinations and in adulthood, although variation is considerable, with some individuals moving away from high fatness categories, while some lean children move into higher fatness categories.

In cross-sectional studies, active children and adolescents tend to have lower skinfold thicknesses and less overall body fat than their less active peers ( Loftin et al., 1998 ; Rowlands et al., 2000 ; Stevens et al., 2004 ; Lohman et al., 2006 ), although the correlations are modest, reflecting variation in body composition at different levels of physical activity, as well as the difficulty of measuring physical activity. Longitudinal studies indicate small differences in fatness between active and inactive boys and girls. Although some school-based studies of the effects of physical activity on body composition have reported changes in BMI or skinfolds in the desired direction ( Gortmaker et al., 1999 ; McMurray et al., 2002 ), most have not shown significant effects. High levels of physical activity are most likely needed to modify skinfold thicknesses and percent body fat. In adults, visceral adipose tissue declines with weight loss with exercise. In contrast, in a study of obese children aged 7-11, a 4-month physical activity program resulted in minimal change in abdominal visceral adipose tissue but a significant loss in abdominal subcutaneous adipose tissue ( Gutin and Owens, 1999 ). In adults, decreases in fatness with exercise are due to a reduction in fat cell size, not number ( You et al., 2006 ); whether this is true in children is not certain but appears likely. Given that adipocyte hypertrophy may trigger adipocyte hyperplasia ( Ballor et al., 1998 ), energy expenditure through regular physical activity may be important in preventing excess adipose tissue cellularity. Regular physical activity also affects adipose tissue metabolism so that trained individuals have an increased ability to mobilize and oxidize fat, which is associated with increased levels of lipolysis, an increased respiratory quotient, and a lower risk of obesity ( Depres and Lamarche, 2000 ).

Cardiorespiratory System

The ability to perform sustained activity under predominantly aerobic conditions depends on the capacity of the cardiovascular and pulmonary systems to deliver oxygenated blood to tissues and on the ability of tissues (primarily skeletal muscle) to extract oxygen and oxidize substrate. By age 2 the systems are fully functional, although young children lack the cardiorespiratory capacity of older children and adults because of their small size ( Malina et al., 2004 ). Children's aerobic capacity and consequently their ability to exercise for longer periods of time increase as they grow. Maximal aerobic power (liters per minute) increases fairly linearly in boys until about age 16, whereas it increases in girls until about age 13 and then plateaus during adolescence ( Malina et al., 2004 ; Eisenmann et al., 2011 ). Differences between boys and girls are small (~10 percent) during childhood and greater after the adolescent growth spurt, when girls have only about 70 percent of the mean value of boys. Changes with age and sex differences are explained largely by differences in the size of the relevant tissues. Dimensions of the heart and lungs enlarge with age in a manner consistent with the increase in body mass and stature ( Malina et al., 2004 ). The increase in the size of the heart is associated with increases in stroke volume (blood pumped per beat) and cardiac output (product of stroke volume and heart rate, liters per minute), despite a decline in heart rate during growth. Similarly, increase in lung size (proportional to growth in height) results in greater lung volume and ventilation despite an age-associated decline in breathing frequency. From about age 6 to adulthood, maximal voluntary ventilation approximately doubles (50–100 L/min) ( Malina et al., 2004 ). The general pattern of increase as a function of height is similar in boys and girls. In both, lung function tends to lag behind the increase in height during the adolescent growth spurt. As a result, peak gains in lung function occur about 2 years earlier in girls than in boys.

Blood volume is highly related to body mass and heart size in children and adolescents, and it is also well correlated with maximal oxygen uptake during childhood and adolescence ( Malina et al., 2004 ). Blood volume increases from birth through adolescence, following the general pattern for changes in body mass. Both red blood cells and hemoglobin have a central role in transport of oxygen to tissues. Hematocrit, the percentage of blood volume explained by blood cells, increases progressively throughout childhood and adolescence in boys, but only through childhood in girls. Hemoglobin content, which is related to maximal oxygen uptake, heart volume, and body mass, increases progressively with age into late adolescence. Males have greater hemoglobin concentrations than females, especially relative to blood volume, which has functional implications for oxygen transport during intense exercise.

Growth in maximal aerobic power is influenced by growth in body size, so controlling for changes in body size during growth is essential. Although absolute (liters per minute) aerobic power increases into adolescence relative to body weight, there is a slight decline in both boys and girls, suggesting that body weight increases at a faster rate than maximal oxygen consumption, particularly during and after the adolescent growth spurt ( Malina et al., 2004 ). Changes in maximal oxygen consumption during growth tend to be related more closely to fat-free mass than to body mass. Nevertheless, sex differences in maximal oxygen consumption per unit fat-free mass persist, and maximal oxygen consumption per unit fat-free mass declines with age.

Improvements in cardiorespiratory function—involving structural and functional adaptations in the lungs, heart, blood, and vascular system, as well as the oxidative capacity of skeletal muscle—occur with regular vigorous- and moderate-intensity physical activity ( Malina et al., 2004 ). Concern about the application of invasive techniques limits the available data on adaptations in the oxygen transport system in children. Nevertheless, it is clear that aerobic capacity in youth increases with activity of sufficient intensity and that maximal stroke volume, blood volume, and oxidative enzymes improve after exercise training ( Rowland, 1996 ). Training-induced changes in other components of the oxygen transport system remain to be determined.

Health- and Performance-Related Fitness

Physical fitness is a state of being that reflects a person's ability to perform specific exercises or functions and is related to present and future health outcomes. Historically, efforts to assess the physical fitness of youth focused on measures designed to evaluate the ability to carry out certain physical tasks or activities, often related to athletic performance. In more recent years, the focus has shifted to greater emphasis on evaluating health-related fitness ( IOM, 2012a ) and assessing concurrent or future health status. Health- and performance-related fitness, while overlapping, are different constructs. Age- and sex-related changes in the components of both are strongly linked to the developmental changes in tissues and systems that occur during childhood and adolescence. Although genetic factors ultimately limit capacity, environmental and behavioral factors, including physical activity, interact with genes to determine the degree to which an individual's full capacity is achieved.

Health-Related Fitness

Cardiorespiratory endurance, muscular strength and endurance, flexibility, and body composition are components of health-related fitness historically assessed in school-based fitness assessment programs ( IOM, 2012a ). These components of health-related fitness are considered important since they can be linked to the risk of cardiometabolic disease and musculoskeletal disability, chronic hypokinetic-related diseases.

Cardiorespiratory endurance

Cardiorespiratory (aerobic) endurance reflects the functioning of the pulmonary and cardiovascular systems to deliver oxygen and the ability of tissues (primarily skeletal muscle) to extract oxygen from the blood. Defined clinically as the maximum oxygen consumption during a maximal graded exercise test, in practice it is usually measured indirectly as performance on a field test of endurance, such as 1- or 2-mile run time ( IOM, 2012a ). During childhood, aerobic capacity approximately doubles in both boys and girls, although girls on average possess a lower capacity. Males continue to improve during adolescence, up to ages 17-18, while aerobic capacity plateaus around age 14 in females ( Malina et al., 2004 ), resulting in an approximately 20 percent difference between males and females ( Rowland, 2005 ).

Favorable associations have been found between aerobic endurance and high-density lipoproteins, systolic blood pressure, diastolic blood pressure, BMI, measures of fatness, arterial stiffness, and measures of insulin sensitivity ( Boreham et al., 2004 ; Imperatore et al., 2006 ; Hussey et al., 2007 ; Ondrak et al., 2007 ). Some evidence suggests a decline in aerobic endurance among U.S. youth in recent decades ( Eisenmann, 2003 ; Carnethon et al., 2005 ; Pate et al., 2006 ), coincident with increased sedentariness and obesity and a greater prevalence of metabolic syndrome in youth. Aerobic exercise has been shown to increase cardiorespiratory endurance by about 5-15 percent in youth ( Malina et al., 2004 ; HHS, 2008 ). The programs that produce this benefit involve continuous vigorous- or moderate-intensity aerobic activity of various types for 30-45 minutes per session at least 3 days per week over a period of at least 1-3 months ( Baquet et al., 2002 ); improvements are greater with more frequent exercise ( Baquet et al., 2003 ).

Muscle strength and endurance

Muscle strength is defined as the highest force generated during a single maximum voluntary contraction, whereas muscle endurance is the ability to perform repeated muscular contraction and force development over a period of time. Muscle strength and endurance are correlated, especially at higher levels of force production. Muscle strength is proportional to the cross-sectional area of skeletal muscle; consequently, strength growth curves parallel growth curves for body weight and skeletal muscle mass ( Malina et al., 2004 ).

Both males and females show impressive increases in muscle strength from childhood to adolescence. Strength in children increases linearly, with boys having a slight advantage over girls. However, these sex differences are magnified during the adolescent years as a result of maturation ( Malina and Roche, 1983 ). Differences in muscle strength between boys and girls become more apparent after puberty, primarily as a result of the production of sex steroid hormones. In boys the increase in strength during adolescence lags behind the growth spurt by at least a year (peak height velocity), which may explain why some boys experience a brief period of clumsiness or awkwardness during puberty, as they have not yet acquired the muscle strength necessary to handle the changes associated with their larger bodies. Muscle strength increases at its greatest rate approximately 1 year after peak height velocity in boys, whereas for girls the strength spurt generally occurs during the same year as peak height velocity ( Bar-Or, 1983 ).

A compelling body of evidence indicates that with resistance training children and adolescents can significantly increase their strength above that expected as a result of normal growth and maturation, provided that the training program is of sufficient intensity, volume, and duration ( Committee on Sports Medicine Fitness, 2001 ). Both boys and girls can benefit, and strength gains in children as young as 5-6 have been reported ( Faigenbaum et al., 2009 ), although most studies are of older children and adolescents. Gains in muscle strength of about 30 percent are typical, although considerably larger gains have been reported. Adolescents make greater gains than preadolescents in absolute strength, whereas reported relative (percent above initial strength) gains in strength during preadolescence and adolescence are similar. A variety of programs and modalities have proved efficacious ( Council on Sports Medicine Fitness, 2008 ), as long as load (~10-15 repetitions maximum) and duration (~8-20 weeks) are adequate. As in adults, training adaptations in youth are specific to the muscle action or muscle groups that are trained, and gains are transient if training is not maintained ( Faigenbaum et al., 2009 ).

Youth resistance training, as with most physical activities, does carry some degree of risk of musculoskeletal injury, yet the risk is no greater than that associated with other sports and activities in which children and adolescents participate ( Council on Sports Medicine Fitness, 2008 ; Faigenbaum et al., 2009 ) as long as age-appropriate training guidelines are followed. A traditional area of concern has been the potential for training-induced damage to growth cartilage, which could result in growth disturbances. However, a recent review found no reports of injury to growth cartilage in any prospective study of resistance training in youth and no evidence to suggest that resistance training negatively impacts growth and maturation during childhood and adolescence ( Faigenbaum et al., 2009 ). Injuries typically occur in unsupervised settings and when inappropriate loads and progressions are imposed.

In addition to the obvious goal of gaining strength, resistance training may be undertaken to improve sports performance and prevent injuries, rehabilitate injuries, and enhance health. Appropriately supervised programs emphasizing strengthening of trunk muscles in children theoretically benefit sport-specific skill acquisition and postural control, although these benefits are difficult to study and thus are supported by little empirical evidence ( Council on Sports Medicine Fitness, 2008 ). Similarly, results are inconsistent regarding the translation of increased strength to enhanced athletic performance in youth. Limited evidence suggests that strength-training programs that address common overuse injuries may help reduce injuries in adolescents, but whether the same is true in preadolescents is unclear ( Council on Sports Medicine Fitness, 2008 ). Increasing evidence suggests that strength training, like other forms of physical activity, has a beneficial effect on measurable health indices in youth, such as cardiovascular fitness, body composition, blood lipid profiles and insulin sensitivity ( Faigenbaum, 2007 ; Benson et al., 2008 ), bone mineral density and bone geometry ( Morris et al., 1997 ; MacKelvie et al., 2004 ), and mental health ( Holloway et al., 1988 ; Faigenbaum et al., 1997 ; Annesi et al., 2005 ; Faigenbaum, 2007 ). Some work has shown that muscle fitness, reflected in a composite index combining measures of muscle strength and endurance, and cardiorespiratory fitness are independently and negatively associated with clustered metabolic risk ( Steene-Johannessen et al., 2009 ). Moreover, children with low muscle strength may be at increased risk of fracture with exercise ( Clark et al., 2011 ). Finally, muscle hypertrophy, which adds to fat-free mass, contributes to resting metabolic rate and therefore total daily energy expenditure. Resistance training may be particularly useful for raising metabolic rate in overweight and obese children without the risk associated with higher-impact activities ( Watts et al., 2005 ; Benson et al., 2007 ).

Flexibility

Flexibility has been operationally defined as “the intrinsic property of body tissues, including muscle and connective tissues, that determines the range of motion achievable without injury at a joint or group of joints” ( IOM, 2012b , p. 190). At all ages, girls demonstrate greater flexibility than boys, and the difference is greatest during the adolescent growth spurt and sexual maturation. Perhaps the most common field measure of flexibility in children and youth is the sit-and-reach test ( IOM, 2012b ) of low-back flexibility. Low-back flexibility as measured by this test is stable in girls from age 5 to 11 and increases until late adolescence. In boys, low-back flexibility declines linearly starting at age 5, reaching its nadir at about age 12, and then increases into late adolescence. The unique pattern of age- and sex-associated variation is related to the growth of the lower extremities and the trunk during adolescence. In boys the nadir in low-back flexibility coincides with the adolescent growth spurt in leg length. In both boys and girls, the increase during adolescence coincides with the growth spurt in trunk length and arm length, which influences reach. Flexibility in both males and females tends to decline after age 17, in part as a result of a decline in physical activity and normal aging.

The principal health outcomes hypothesized to be associated with flexibility are prevention of and relief from low-back pain, prevention of musculoskeletal injury, and improved posture. These associations have been studied in adults, with equivocal results ( Plowman, 1992 ). Although flexibility has long been included in national youth fitness tests, it has proven difficult to establish a link between flexibility and health ( IOM, 2012a ). In contrast to other fitness components that are general or systemic in nature, flexibility is highly specific to each joint of the body. Although appropriate stretching may increase flexibility, establishing a link to improved functional capacity and fitness is difficult. A few studies suggest that improvements in flexibility as measured by the sit-and-reach test may be related to less low-back pain ( Jones et al., 2007 ; Ahlqwist et al., 2008 ), but the evidence is weak. Consequently, the Institute of Medicine (IOM) Committee on Fitness Measures and Health Outcomes in its recent report elected to forego recommending a flexibility test for a national youth fitness test battery pending further research to confirm the relationship between flexibility and health and to develop national normative data ( IOM, 2012a ).

Body composition

Body composition is the component of health-related fitness that relates to the relative amount of adipose tissue, muscle, bone, and other vital components (e.g., organs, connective tissues, fluid compartments) that make up body weight. Most feasible methods for assessing body composition are based on models that divide the body into fat and fat-free (all nonfat constituents) components ( Going et al., 2012 ). Although fat mass and adipose tissue are not equivalent components, fat mass is easier to estimate than adipose tissue, and it is correlated with performance and disease risk. In settings in which estimation of body fat is difficult, weight-for-height ratios often are used as surrogates for body composition. Indeed, definitions of pediatric overweight and obesity have been based on BMI, calculated as weight in kilograms divided by height squared. Child and adolescent obesity defined by BMI remains at all-time highs. Population surveys indicate that approximately 33 percent of all boys and girls are overweight, and nearly one in five are obese ( Ogden and Flegal, 2011 ). The tendency for excess fatness to persist from childhood and adolescence into adulthood ( Daniels et al., 2005 ), coupled with the strong association between obesity and chronic disease ( Weiss and Caprio, 2005 ; Barlow, 2007 ), has caused great concern for future obesity levels and the health of youth and adults alike ( IOM, 2005 , 2012b ).

The increase in prevalence of obesity is undoubtedly due to a mismatch between energy intake and expenditure. Population surveys have shown that few children and youth meet recommended levels of daily physical activity (see Chapter 2 ). Prospective studies have shown a significant and inverse relationship between habitual physical activity and weight gain ( Berkey et al., 2003 ), and in some studies physical activity is a better predictor of weight gain than estimates of calorie or fat intake ( Berkey et al., 2000 ; Janssen et al., 2005 ). These relationships are better established in adults than in children and youth, although even in preschool children, low levels of physical activity, estimated from doubly labeled water, were found to be indicative of higher body fat content ( Davies et al., 1995 ). While studies of exercise without caloric restriction generally show only small effects on body weight, significant albeit moderate reductions of body fat are generally reported ( Eisenmann, 2003 ). Moreover, even in the absence of significant weight loss, exercise has beneficial effects on risk factors for cardiometabolic disease ( Ross and Bradshaw, 2009 ; Gutin and Owens, 2011 ).

Body mass index

Changes in weight for height with growth and maturation for U.S. boys and girls are described in CDC growth curves ( Kuczmarski et al., 2000 ). Current growth curves were derived from U.S. population surveys conducted before the increase in weight for height that defines today's pediatric obesity epidemic. In boys and girls, BMI declines during early childhood, reaching its nadir at about ages 5-6, and then increases through adolescence. A gender difference emerges during puberty, with males gaining greater fat-free mass than females. Both the period of “adiposity rebound” (the increase in BMI in midchildhood following the decline in early childhood) and puberty are times of risk for excess fat gain that correlates with future adiposity ( Rolland-Cachera et al., 1984 ). Physical activity and BMI are inversely correlated in children and adolescents, although the correlations are modest ( Lohman et al., 2006 ), reflecting the difficulty of measuring physical activity, as well as variation in body composition and physical activity at a given weight ( Rowlands et al., 2000 ). Indeed, when studied separately, fat mass index (FMI, or fat mass divided by height squared) and fat-free mass index (FFMI, or fat-free mass divided by height squared) are both inversely related to physical activity. With FMI controlled, however, FFMI is positively related to physical activity, indicating that, for a given level of body fat, individuals with more fat-free mass are more active ( Lohman et al., 2006 ). BMI cut-points for defining overweight and obesity have historically been based on age- and gender-specific population distributions of BMI. Recent work has shown good correspondence between BMI standards and percent fat standards that are referenced to health criteria ( Laurson et al., 2011 ). These new standards should prove useful for identifying children and adolescents at risk for higher levels of cardiometabolic risk factors.

Percent body fat

Direct measures of body fat as a percent of weight provide a better index of adiposity and health risk than BMI ( Zeng et al., 2012 ), which is confounded by variation in lean tissue mass relative to height. Recently, percent fat growth curves were established for representative samples of U.S. boys and girls using National Health and Nutrition Examination Survey (NHANES) data ( Laurson et al., 2011 ; Ogden and Flegal, 2011 ). Median percent fat for boys aged 5-18 ranged from 14 to 19 percent and for girls across the same ages 15 to 28 percent. In both boys and girls, percent fat increases slowly during early childhood, with girls having a consistently greater relative fatness than boys after ages 5-6. In girls, percent fat increases gradually throughout adolescence in the same manner as fat mass. In boys, percent fat increases gradually until the adolescent growth spurt and thereafter gradually declines until about age 16-17, reflecting the rapid growth in fat-free mass relative to fat mass. After age 17, percent fat in males gradually increases again into adulthood.

The increased prevalence of child and adolescent obesity as defined by BMI presumably also reflects increased adiposity, although the degree is not certain as population-based estimates of percent fat have only recently been developed ( Laurson et al., 2011 ). Health-related percent fat standards recently were developed by determining levels of body fat associated with greater occurrence of chronic disease risk factors defined by metabolic syndrome ( Going et al., 2011 ). In boys and girls aged 12-18, body fat above 20-24 percent and above 27-31 percent, respectively, was predictive of metabolic syndrome.

Physical activity is inversely correlated with percent body fat ( Rowlands et al., 2000 ; Lohman et al., 2006 ), although the correlations are modest, and changes in overall fatness as well as subcutaneous adipose tissue with habitual physical activity are reasonably well documented in children and adolescents ( Gutin and Humphries, 1998 ; Gutin and Owens, 1999 ; Dionne et al., 2000 ). In youth, as in adults, the effects of exercise without caloric restriction are modest and are influenced by the initial level of body fat and the duration and regimen of exercise ( Going, 1999 ). Experimental studies have documented reductions in percent body fat with aerobic exercise, especially in children and adolescents who are overweight or obese at the initiation of an exercise program ( Davis et al., 2012 ). Regular physical activity also affects adipose tissue metabolism ( Gutin and Owens, 1999 ). Individuals who engage in aerobic endurance exercise training have an increased ability to mobilize and oxidize fat, which is associated with increased levels of lipolysis ( Depres and Lamarche, 2000 ). Similar information on adipose tissue metabolism in children and youth is lacking, although one can reasonably expect similar adaptations in older adolescents.

Metabolic syndrome

The tendency for risk factors for cardiometabolic disease to cluster, now called metabolic syndrome, is well recognized in adults ( Alberti and Zimmet, 1998 ). Similar clustering occurs in older children and especially adolescents ( Cook et al., 2003 ), and interest in metabolic syndrome has increased, driven by the increased prevalence of pediatric obesity and the increasing incidence and earlier onset of type 2 diabetes in youth. There is as yet no accepted definition of metabolic syndrome for use in pediatric populations ( Jolliffe and Janssen, 2007 ). Typically, adult definitions are extrapolated to children and adolescents, with appropriate adjustments of the thresholds for the defining variables. Perhaps the most common approach is to emulate the National Cholesterol Education Program (NCEP), which defines metabolic syndrome as exceeding thresholds on three of five components: waist circumference, blood pressure (systolic or diastolic), blood lipids (high-density lipoprotein [HDL] and triglycerides), and blood glucose levels ( NIH, 2001 ).

The concept of metabolic syndrome is useful as it provides an integrated index of risk, and it recently was used to derive health-related percent-body-fat standards ( Laurson et al., 2011 ). Based on NHANES data, the prevalence of metabolic syndrome varies with the degree of obesity, and it is estimated at 4-6 percent of children and adolescents ( Cook et al., 2003 ; Dubose et al., 2007 ); among obese youth it may be as high as 30-50 percent ( Weiss et al., 2004 ). Youth with metabolic syndrome have an increased risk of type 2 diabetes and cardiovascular disease. In adults a loss of 5-10 percent of body weight through calorie restriction and exercise has been shown to reduce the risk of cardiometabolic disease by improving risk factors ( Diabetes Prevention Program Research Group, 2002 ; Ross and Janiszewski, 2008 ). In particular, weight loss results in reduced visceral adipose tissue, a strong correlate of risk ( Knowler et al., 2002 ), as well as lower blood pressure and blood glucose levels due to improved insulin sensitivity. Even without significant weight loss, exercise can have significant effects in adults by improving glucose metabolism, improving lipid and lipoprotein profiles, and lowering blood pressure, particularly for those who are significantly overweight ( Ross and Bradshaw, 2009 ). Similar benefits have been observed in adolescents.

A growing body of literature addresses the associations of physical activity, physical fitness, and body fatness with the risk of metabolic syndrome and its components in children and especially adolescents ( Platat et al., 2006 ; McMurray et al., 2008 ; Rubin et al., 2008 ; Thomas and Williams, 2008 ; Christodoulos et al., 2012 ). Studies in adults have shown that higher levels of physical activity predict slower progression toward metabolic syndrome in apparently healthy men and women ( Laaksonen et al., 2002 ; Ekelund et al., 2005 ), an association that is independent of changes in body fatness and cardiorespiratory fitness ( Ekelund et al., 2007 ). Few population studies have focused on these relationships in children and adolescents, and the use of self-reported activity, which is imprecise in these populations, tends to obscure associations. In a large sample of U.S. adolescents aged 12-19 in the 1999–2002 NHANES, for example, there was a trend for metabolic syndrome to be more common in adolescents with low activity levels than in those with moderate or high activity levels, although the differences among groups were not statistically significant ( Pan and Pratt, 2008 ). Moreover, for each component of metabolic syndrome, prevalence was generally lower with higher physical activity levels, and adolescents with low physical activity levels had the highest rates of all metabolic syndrome components.

The association between cardiorespiratory fitness and metabolic syndrome also was examined in the 1999–2002 NHANES ( Lobelo et al., 2010 ). Cardiorespiratory fitness was measured as estimated peak oxygen consumption using a submaximal treadmill exercise protocol, and metabolic syndrome was represented as a “clustered score” derived from five established risk factors for cardiovascular disease, an adiposity index, insulin resistance, systolic blood pressure, triglycerides, and the ratio of total to HDL cholesterol. Mean clustered risk score decreased across increasing fifths (quintiles) of cardiorespiratory fitness in both males and females. The most significant decline in risk score was observed from the first (lowest) to the second quintile (53.6 percent and 37.5 percent in males and females, respectively), and the association remained significant in both overweight and normal-weight males and in normal-weight females. Other studies, using the approach of cross-tabulating subjects into distinct fitness and fatness categories, have examined associations of fitness and fatness with metabolic syndrome risk ( Eisenmann et al., 2005 , 2007a , b ; Dubose et al., 2007 ). Although different measures of fitness, fatness, and metabolic syndrome risk were used, the results taken together across a wide age range (7–18) show that fitness modifies the influence of fatness on metabolic syndrome risk. In both males and females, high-fit/low-fatness subjects have less metabolic syndrome risk than low-fit/high-fatness subjects ( Eisenmann, 2007 ).

That many adult chronic health conditions have their origins in childhood and adolescence is well supported ( Kannel and Dawber, 1972 ; Lauer et al., 1975 ; Berenson et al., 1998 ; IOM, 2004 ). Both biological (e.g., adiposity, lipids) and behavioral (e.g., physical activity) risk factors tend to track from childhood and especially adolescence into adulthood. Childhood BMI is related to adult BMI and adiposity ( Guo et al., 1994 , 2000 ; Freedman et al., 2005 ), and as many as 80 percent of obese adolescents become obese adults ( Daniels et al., 2005 ). Coexistence of cardiometabolic risk factors, even at young ages ( Dubose et al., 2007 ; Ramírez-Vélez et al., 2012 ), has been noted, and these components of metabolic syndrome also have been shown to track to adulthood ( Bao et al., 1994 ; Katzmarzyk et al., 2001 ; Huang et al., 2008 ). Landmark studies from the Bogalusa Heart Study ( Berenson et al., 1998 ; Li et al., 2003 ) and others ( Mahoney et al., 1996 ; Davis et al., 2001 ; Morrison et al., 2007 , 2008 ) have demonstrated that cardiometabolic risk factors present in childhood are predictive of adult disease.

The benefits of exercise for prevention and treatment of cardiometabolic disease in adults are well described ( Ross et al., 2000 ; Duncan et al., 2003 ; Gan et al., 2003 ; Irwin et al., 2003 ; Lee et al., 2005 ; Sigal et al., 2007 ; Ross et al., 2012 ). Prospective studies examining the effects of exercise on metabolic syndrome in children and adolescents remain limited, and it is important to refrain from extrapolating intervention effects observed in adults to youth, although one might reasonably assume the benefits in older adolescents to be similar to those in young adults. Indeed, based on the inverse associations of physical activity and physical fitness with metabolic syndrome ( Kim and Lee, 2009 ) and on the available intervention studies, some experts have recommended physical activity as the main therapeutic tool for prevention and treatment of metabolic syndrome in childhood ( Brambilla et al., 2010 ). Comparative studies in adults have shown that the effect of exercise on weight is limited and generally less than that of calorie restriction ( Brambilla et al., 2010 ). Moreover, the relative effectiveness of diet and exercise depends on the degree of excess fatness ( Brambilla et al., 2010 ). Comparative studies in children and youth are few, as behavioral interventions in overweight children and adolescents commonly combine exercise and dietary restriction, making it difficult to disentangle their independent effects. Nonetheless, diet and exercise have different effects on body composition: While both contribute to fat loss, only exercise increases muscle mass and thus has a direct effect on metabolic health. In children and youth, as in adults, the effect of exercise on cardiometabolic risk factors is greater in overweight/obese youth than in their normal-weight peers ( Kang et al., 2002 ; Lazaar et al., 2007 ).

Exercise also may have important benefits even without significant modification of body composition ( Bell et al., 2007 ). Experimental studies in overweight and obese youth have shown that exercise leads to reductions in visceral fat ( Owens et al., 1999 ; Gutin et al., 2002 ; Lee at al., 2005 ; Barbeau et al., 2007 ; Kim and Lee, 2009 ) without a significant change in BMI, as well as improvement in markers of metabolic syndrome, primarily fasting insulin and insulin resistance ( Treuth et al., 1998 ; Ferguson et al., 1999 ; Carrel et al., 2005 ; Nassis et al., 2005 ; Meyer et al., 2006 ; Shaibi et al., 2006 ; Bell et al., 2007 ). Results from experimental studies of the effects of exercise on lipids and lipoproteins ( Stoedefalke et al., 2000 ; Kelley and Kelley, 2008 ; Janssen and LeBlanc, 2010 ) are mixed. Although some studies have shown improved lipid and lipoprotein profiles, primarily a decrease in low-density lipoprotein (LDL) cholesterol and triglyceride concentrations and an increase in HDL cholesterol ( Ferguson et al., 1999 ), other studies have shown no improvement in these outcomes ( Kelley and Kelley, 2008 ). In part, such conflicting results are likely due to initial differences in body composition and severity of hyperlipidemia. Well-controlled exercise training studies in obese children ( Escalante et al., 2012 ) and children with adverse blood lipid and lipoprotein profiles have shown positive alterations in their profiles ( Stoedefalke et al., 2000 ), whereas results in normolipid-emic children and adolescents are equivocal. Similarly, exercise has little effect on resting blood pressure in normotensive children and adolescents ( Kelley and Kelley, 2008 ), whereas reductions in resting systolic and sometimes diastolic pressures have been reported in youth with high blood pressure ( Hagberg et al., 1983 , 1984 ; Danforth et al., 1990 ; Ewart et al., 1998 ; Farpour-Lambert et al., 2009 ; Janssen and LeBlanc, 2010 ).

In adults, physical activity is inversely associated with low-grade inflammation ( Wärnberg et al., 2010 ; Ertek and Cicero, 2012 ), which is now recognized as a significant feature of metabolic syndrome and an independent predictor of cardiometabolic disease ( Malina, 2002 ). In obese children and adolescents, as in their adult counterparts, elevation of inflammatory markers is evident, and observational studies have shown significant relationships among physical activity, physical fitness, and inflammation ( Isasi et al., 2003 ; Platat et al., 2006 ; Ruiz et al., 2007 ; Wärnberg et al., 2007 ; Wärnberg and Marcos, 2008 ). These relationships are better studied and stronger in adolescents than in children. In one study of boys and girls aged 10-15, those who were obese and unfit had the highest levels of systemic inflammation, whereas those who were obese yet fit had levels as low as those who were lean and fit ( Halle et al., 2004 ). In another study, low-grade inflammation was negatively associated with muscle strength in overweight adolescents after controlling for cardiorespiratory fitness, suggesting that high levels of muscle strength may counteract some of the negative consequences of higher levels of body fat ( Ruiz et al., 2008 ). Experimental studies of the effects of exercise and markers of low-grade inflammation in children and adolescents are lacking. Improved cardiorespiratory fitness in adults ( Church et al., 2002 ), however, has been shown to be inversely related to concentration of C-reactive protein (CRP), a marker of low-grade inflammation. In a small study of a lifestyle intervention entailing 45 minutes of physical activity 3 times per week for 3 months, a small reduction in body fat and an overall decrease in inflammatory factors (CRP, interleukin [IL]-6) were seen in obese adolescents ( Balagopal et al., 2005 ).

Performance-Related Fitness

Speed, muscle power, agility, and balance (static and dynamic) are aspects of performance-related fitness that change during body development in predictable ways associated with the development of tissues and systems discussed above ( Malina et al., 2004 ). Running speed and muscle power are related, and both depend on full development of the neuromuscular system. Running speed and muscle power are similar for boys and girls during childhood ( Haubenstricker and Seefeldt, 1986 ). After puberty, largely because of differences in muscle mass and muscle strength, males continue to make significant annual gains, while females tend to plateau during the adolescent years. Sociocultural factors and increasing inactivity among girls relative to boys, along with changes in body proportion and a lowering of the center of gravity, may also contribute to gender differences ( Malina et al., 2004 ).

Balance—the ability to maintain equilibrium—generally improves from ages 3 to 18 ( Williams, 1983 ). Research suggests that females outperform males on tests of static and dynamic balance during childhood and that this advantage persists through puberty ( Malina et al., 2004 ).

Motor performance is related in part to muscle strength. Increases in muscle strength as a result of resistance exercise were described above. A question of interest is whether gains in strength transfer to other performance tasks. Available results are variable, giving some indication that gains in strength are associated with improvement in some performance tasks, such as sprinting and vertical jump, although the improvements are generally small, highlighting the difficulty of distinguishing the effects of training from changes expected with normal growth. Changes in body size, physique, and body composition associated with growth and maturation are important factors that affect strength and motor performance. The relationships vary among performance measures and with age, and these factors often are inadequately controlled in studies of components of performance-related fitness and performance tasks.

PSYCHOSOCIAL HEALTH

Research supports the positive impact of physical activity on the overall psychological health and social engagement of every student. A well-designed physical education curriculum provides students with social and emotional benefits ( NASPE, 2001 ). Simultaneously, exposure to failure experiences, emphasis on competitive sports, and elitism for naturally inclined athletes, along with bullying and teasing of unfit, uncoordinated, and overweight youth, may be important factors discouraging participation in current and future physical activity ( Kohl and Hobbs, 1998 ; Sallis et al., 2000 ; Allender et al., 2006 ). School-based physical activity, including physical education and sports, is designed to increase physical activity while also improving motor skills and development, self-efficacy, and general feelings of competency and engaging children socially ( Bailey, 2006 ). The hoped-for psychosocial outcomes of physical education and other physical activity programs in the school setting have been found to be critical for continued physical activity across the life span and are themselves powerful long-term determinants of physical activity ( Bauman et al., 2012 ). Unfortunately, significant gaps exist between the intent and reality of school-based physical education and other activity programs ( HHS, 2013 ).

A large number of psychological and social outcomes have been examined. Specific aspects of psychosocial health showing a beneficial relationship to physical activity include, among others, self-efficacy, self-concept, self-worth ( Haugen et al., 2011 ), social behaviors ( Cradock et al., 2009 ), pro-school attitudes, motivation and goal orientation ( Digelidis et al., 2003 ), relatedness, friendships ( de la Haye et al., 2011 ; Macdonald-Wallis et al., 2011 ), task orientation, team building, bullying, and racial prejudice ( Byrd and Ross, 1991 ). Most studies are descriptive, finding bidirectional associations between psychosocial outcomes and physical activity. Reviews and meta-analyses confirm a positive association between physical activity and self-esteem, especially for aerobic activities ( McAuley, 1994 ).

Among psychosocial factors, self-efficacy (confidence in one's ability to be physically active in specific situations) has emerged as an important correlate of physical activity from a large body of work based on the durable and practically useful social learning theory ( Bandura and McClelland, 1977 ; Bandura, 1995 ). Bandura's theory compels consideration of the psychosocial and physical environments, the individual, and in this case the behavior of physical activity. Using this framework, physical activity itself has been shown to be a consistent positive correlate as well as a determinant of physical activity in children and adolescents. A large amount of reviewed research has found that physical education and physical activity experiences can increase children's confidence in being active and lead to continued participation in physical activity ( Bauman et al., 2012 ). RCTs have shown that both self-efficacy and social interactions leading to perceived social support influence changes in physical activity ( Dishman et al., 2009 ). Skill mastery, confidence building, and group support are well-known strategies for advancing student learning and well-being in many educational domains in the school setting and apply equally to school physical education and other physical activity. Early observational studies of physical, social, and environmental determinants of physical activity at home, school, and recess indicated that prompts to be active (or not) from peers and adults accounted for a significant amount of the variance in directly observed physical activity ( Elder et al., 1998 ). One longitudinal study following the variability and tracking of physical activity in young children showed that most of the variability in both home and recess activity was accounted for by short-term social and physical environmental factors, such as prompts from others and being outdoors ( Sallis et al., 1995 ). Another study, examining activity among preschool children, found that, contrary to common belief, most of the time spent in preschool was sedentary, and correlates of activity were different for preschool boys and girls ( Byun et al., 2011 ). In addition, significant variation in activity by preschool site was noted, indicating that local environmental conditions, including physical environment and equipment, policies, and teacher and administrative quality characteristics, play an important role in promoting physical activity ( Brown et al., 2009 ).

Studies in middle and high school populations have strengthened the evidence base on relationships among self-efficacy, physical activity, and social support (from adults and peers). This research has highlighted the central contribution of self-efficacy and social support in protecting against a decline in activity levels among adolescent girls ( Dishman et al., 2009 , 2010 ). Evidence indicates further that these impacts spread to activities outside the school setting ( Lytle et al., 2009 ). Findings of a related study suggest that leisure-time physical activity among middle school students was linked to motivation-related experiences in physical education ( Cox et al., 2008 ).

A recent review of reviews ( Bauman et al., 2012 ) found that population levels of physical activity are low and that consistent individual-level correlates of physical activity are age, sex, health status, self-efficacy, and previous physical activity. Physical activity declines dramatically as children progress from elementary through high school ( Nader et al., 2008 ). Boys are consistently found to be more active than girls from ages 4 to 9. For other age groups of children and adolescents, sex is correlated with but not a determinant of activity ( Bauman et al., 2012 ). These findings suggest the need to tailor physical education and physical activity programs for youth specifically to increase self-efficacy and enjoyment of physical activity among girls ( Dishman et al., 2005 ; Barr-Anderson et al., 2008 ; Butt et al., 2011 ).

In summary, a broad range of beneficial psychosocial health outcomes have been associated with physical activity. The promotion of more physical activity and quality physical education in the school setting is likely to result in psychosocially healthier children who are more likely to engage in physical activity as adults. Schools can play an important role in ensuring opportunities for physical activity for a segment of the youth population that otherwise may not have the resources to engage in such activity. It makes sense to assume that, if physical activity experiences and environments were once again structured into the daily school environment of children and adolescents, individuals' feelings of self-efficacy regarding physical activity would increase in the U.S. population.

MENTAL HEALTH

Mental illness is a serious public health issue. It has been estimated that by 2010 mental illness will account for 15 percent of the global burden of disease ( Biddle and Mutrie, 2008 ; Biddle and Asare, 2011 ). Young people are disproportionately affected by depression, anxiety, and other mental health disorders ( Viner and Booy, 2005 ; Biddle and Asare, 2011 ). Approximately 20 percent of school-age children have a diagnosable mental health disorder ( U.S. Public Health Service, 2000 ), and overweight children are at particular risk ( Ahn and Fedewa, 2011 ). Mental health naturally affects academic performance on many levels ( Charvat, 2012 ). Students suffering from depression, anxiety, mood disorders, and emotional disturbances perform more poorly in school, exhibit more behavioral and disciplinary problems, and have poorer attendance relative to mentally healthy children. Thus it is in schools' interest to take measures to support mental health among the student population. In addition to other benefits, providing adequate amounts of physical activity in a way that is inviting and safe for children of all ability levels is one simple way in which schools can contribute to students' mental health.

Impact of Physical Activity on Mental Health

Several recent reviews have concluded that physical activity has a positive effect on mental health and emotional well-being for both adults and children ( Peluso and Guerra de Andrade, 2005 ; Penedo and Dahn, 2005 ; Strong et al., 2005 ; Hallal et al., 2006 ; Ahn and Fedewa, 2011 ; Biddle and Asare, 2011 ). Numerous observational studies have established the association between physical activity and mental health but are inadequate to clarify the direction of that association ( Strong et al., 2005 ). It may be that physical activity improves mental health, or it may be that people are more physically active when they are mentally healthy. Most likely the relationship is bidirectional.

Several longitudinal and intervention studies have clarified that physical activity positively impacts mental health ( Penedo and Dahn, 2005 ; Strong et al., 2005 ). Physical activity has most often been shown to reduce symptoms of depression and anxiety and improve mood ( Penedo and Dahn, 2005 ; Dishman et al., 2006 ; Biddle and Asare, 2011 ). In addition to reducing symptoms of depression and anxiety, studies indicate that regular physical activity may help prevent the onset of these conditions ( Penedo and Dahn, 2005 ). Reductions in depression and anxiety are the commonly measured outcomes ( Strong et al., 2005 ; Ahn and Fedewa, 2011 ). However, reductions in states of confusion, anger, tension, stress, anxiety sensitivity (a precursor to panic attacks and panic disorders), posttraumatic stress disorder/psychological distress, emotional disturbance, and negative affect have been observed, as well as increases in positive expectations; fewer emotional barriers; general well-being; satisfaction with personal appearance; and improved life satisfaction, self-worth, and quality of life ( Heller et al., 2004 ; Peluso and Guerra de Andrade, 2005 ; Penedo and Dahn, 2005 ; Dishman et al., 2006 ; Hallal et al., 2006 ; Ahn and Fedewa, 2011 ; Biddle and Asare, 2011 ). Among adolescents and young adult females, exercise has been found to be more effective than cognitive-behavioral therapy in reducing the pursuit of thinness and the frequency of bingeing, purging, and laxative abuse ( Sundgot-Borgen et al., 2002 ; Hallal et al., 2006 ). The favorable effects of physical activity on sleep may also contribute to mental health ( Dishman et al., 2006 ).

The impact of physical activity on these measures of mental health is moderate, with effect sizes generally ranging from 0.4 to 0.7 ( Biddle and Asare, 2011 ). In one meta-analysis of intervention trials, the RCTs had an effect size of 0.3, whereas other trials had an effect size of 0.57.

Ideal Type, Length, and Duration of Physical Activity

Intervention trials that examine the relationship between physical activity and mental health often fail to specify the exact nature of the intervention, making it difficult to determine the ideal frequency, intensity, duration, and type of physical activity involved ( Penedo and Dahn, 2005 ; Ahn and Fedewa, 2011 ; Biddle and Asare, 2011 ).

Many different types of physical activity—including aerobic activity, resistance training, yoga, dance, flexibility training, walking programs, and body building—have been shown to improve mood and other mental health indicators. The evidence is strongest for aerobic physical activity, particularly for reduction of anxiety symptoms and stress ( Peluso and Guerra de Andrade, 2005 ; Dishman et al., 2006 ; Martikainen et al., 2013 ), because more of these studies have been conducted ( Peluso and Guerra de Andrade, 2005 ). One meta-analysis of RCTs concluded that physical activity interventions focused exclusively on circuit training had the greatest effect on mental health indicators, followed closely by interventions that included various types of physical activity ( Ahn and Fedewa, 2011 ). Among studies other than RCTs, only participation in sports had a significant impact on mental health ( Ahn and Fedewa, 2011 ). The few studies that investigated the impact of vigorous- versus lower-intensity physical activity ( Larun et al., 2006 ; Biddle and Asare, 2011 ) found no difference, suggesting that perhaps all levels of physical activity may be helpful. Among adults, studies have consistently shown beneficial effects of both aerobic exercise and resistance training. Ahn and Fedewa (2011) concluded that both moderate and intense physical activity have a significant impact on mental health, although when just RCTs were considered, only intense physical activity was significant ( Ahn and Fedewa, 2011 ). While physical activity carries few risks for mental health, it is important to note that excessive physical activity or specialization too early in certain types of competitive physical activity has been associated with negative mental health outcomes and therefore should be avoided ( Peluso and Guerra de Andrade, 2005 ; Hallal et al., 2006 ). Furthermore, to reach all children, including those that may be at highest risk for inactivity, obesity, and mental health problems, physical activity programming needs to be nonthreatening and geared toward creating a positive experience for children of all skill and fitness levels ( Amis et al., 2012 ).

Various types of physical activity programming have been shown to have a positive influence on mental health outcomes. Higher levels of attendance and participation in physical education are inversely associated with feelings of sadness and risk of considering suicide ( Brosnahan et al., 2004 ). Classroom physical activity is associated with reduced use of medication for attention deficit hyperactivity disorder ( Katz et al., 2010 ). And participation in recess is associated with better student classroom behavior, better focus, and less fidgeting ( Pellegrini et al., 1995 ; Jarrett et al., 1998 ; Barros et al., 2009 ).

Strong evidence supports the short-term benefits of physical activity for mental health. Acute effects can be observed after just one episode and can last from a few hours to up to 1 day after. Body building may have a similar effect, which begins a few hours after the end of the exercise. The ideal length and duration of physical activity for improving mental health remain unclear, however. Regular exercise is associated with improved mood, but results are inconsistent for the association between mood and medium- or long-term exercise ( Dua and Hargreaves, 1992 ; Slaven and Lee, 1997 ; Dimeo et al., 2001 ; Dunn et al., 2001 ; Kritz-Silverstein et al., 2001 ; Sexton et al., 2001 ; Leppamaki et al., 2002 ; Peluso and Guerra de Andrade, 2005 ). Studies often do not specify the frequency and duration of physical activity episodes; among those that do, interventions ranged from 6 weeks to 2 years in duration. In their meta-analysis, Ahn and Fedewa (2011) found that, comparing interventions entailing a total of more than 33 hours, 20-33 hours, and less than 20 hours, the longer programs were more effective. Overall, the lack of reporting and the variable length and duration of reported interventions make it difficult to draw conclusions regarding dose ( Ahn and Fedewa, 2011 ).

In addition to more structured opportunities, naturally occurring physical activity outside of school time is associated with fewer depressive symptoms among adolescents ( Penedo and Dahn, 2005 ). RCTs have demonstrated that physical activity involving entire classrooms of students is effective in alleviating negative mental health outcomes ( Ahn and Fedewa, 2011 ). Non-RCT studies have shown individualized approaches to be most effective and small-group approaches to be effective to a more limited extent ( Ahn and Fedewa, 2011 ). Interventions have been shown to be effective in improving mental health when delivered by classroom teachers, physical education specialists, or researchers but may be most effective when conducted with a physical education specialist ( Ahn and Fedewa, 2011 ). Many physical activity interventions include elements of social interaction and support; however, studies to date have been unable to distinguish whether the physical activity itself or these other factors account for the observed effects on mental health ( Hasselstrom et al., 2002 ; Hallal et al., 2006 ). Finally, a few trials ( Larun et al., 2006 ; Biddle and Asare, 2011 ) have compared the effects of physical activity and psychosocial interventions, finding that physical activity may be equally effective but may not provide any added benefit.

Subgroup Effects

Although studies frequently fail to report the age of participants, data on the effects of physical activity on mental health are strongest for adults participating in high-intensity physical activity ( Ahn and Fedewa, 2011 ). However, evidence relating physical activity to various measures of mental health has shown consistent, significant effects on individuals aged 11-20. A large prospective study found that physical activity was inversely associated with depression in early adolescence ( Hasselstrom et al., 2002 ; Hallal et al., 2006 ); fewer studies have been conducted among younger children. Correlation studies have shown that the association of physical activity with depression is not affected by age ( Ahn and Fedewa, 2011 ).

Few studies have examined the influence of other sociodemographic characteristics of participants on the relationship between physical activity and mental health ( Ahn and Fedewa, 2011 ), but studies have been conducted in populations with diverse characteristics. One study of low-income Hispanic children randomized to an aerobic intensity program found that the intervention group was less likely to present with depression but did not report reduced anxiety ( Crews et al., 2004 ; Hallal et al., 2006 ). A study that included black and white children (aged 7-11) found that a 40-minute daily dose of aerobic exercise significantly reduced depressive symptoms and increased physical appearance self-worth in both black and white children and increased global self-worth in white children compared with controls ( Petty et al., 2009 ). Physical activity also has been positively associated with mental health regardless of weight status (normal versus overweight) or gender (male versus female) ( Petty et al., 2009 ; Ahn and Fedewa, 2011 ); however, results are stronger for males ( Ahn and Fedewa, 2011 ).

Improvements in mental health as a result of physical activity may be more pronounced among clinically diagnosed populations, especially those with cognitive impairment or posttraumatic stress disorder ( Craft and Landers, 1998 ; Ahn and Fedewa, 2011 ; Biddle and Asare, 2011 ). Evidence is less clear for youth with clinical depression ( Craft and Landers, 1998 ; Larun et al., 2006 ; Biddle and Asare, 2011 ). Individuals diagnosed with major depression undergoing an intervention entailing aerobic exercise have shown significant improvement in depression and lower relapse rates, comparable to results seen in participants receiving psychotropic treatment ( Babyak et al., 2000 ; Penedo and Dahn, 2005 ). One program for adults with Down syndrome providing three sessions of exercise and health education per week for 12 weeks resulted in more positive expectations, fewer emotional barriers, and improved life satisfaction ( Heller et al., 2004 ; Penedo and Dahn, 2005 ). Ahn and Fedewa (2011) found that, compared with nondiagnosed individuals, physical activity had a fivefold greater impact on those diagnosed with cognitive impairment and a twofold greater effect on those diagnosed with emotional disturbance, suggesting that physical activity has the potential to improve the mental health of those most in need.

Sedentary Behavior

Sedentary behavior also influences mental health. Screen viewing in particular and sitting in general are consistently associated with poorer mental health ( Biddle and Asare, 2011 ). Children who watch more television have higher rates of anxiety, depression, and posttraumatic stress and are at higher risk for sleep disturbances and attention problems ( Kappos, 2007 ). Given the cross-sectional nature of these studies, however, the direction of these associations cannot be determined. A single longitudinal study found that television viewing, but not playing computer games, increased the odds of depression after 7-year follow-up ( Primack et al., 2009 ; Biddle and Asare, 2011 ), suggesting that television viewing may contribute to depression. Because of design limitations of the available studies, it is unclear whether this effect is mediated by physical activity.

Television viewing also is associated with violence, aggressive behaviors, early sexual activity, and substance abuse ( Kappos, 2007 ). These relationships are likely due to the content of the programming and advertising as opposed to the sedentary nature of the activity. Television viewing may affect creativity and involvement in community activities as well; however, the evidence here is very limited ( Kappos, 2007 ). Studies with experimental designs are needed to establish a causal relationship between sedentary behavior and mental health outcomes ( Kappos, 2007 ).

Although the available evidence is not definitive, it does suggest that sedentary activity and television viewing in particular can increase the risk for depression, anxiety, aggression, and other risky behaviors and may also affect cognition and creativity ( Kappos, 2007 ), all of which can affect academic performance. It would therefore appear prudent for schools to reduce these sedentary behaviors during school hours and provide programming that has been shown to be effective in reducing television viewing outside of school ( Robinson, 1999 ; Robinson and Borzekowski, 2006 ).

It is not surprising that physical activity improves mental health. Both physiological and psychological mechanisms explain the observed associations. Physiologically, physical activity is known to increase the synaptic transmission of monoamines, an effect similar to that of anti-depressive drugs. Physical activity also stimulates the release of endorphins (endogenous opoids) ( Peluso and Guerra de Andrade, 2005 ), which have an inhibitory effect on the central nervous system, creating a sense of calm and improved mood ( Peluso and Guerra de Andrade, 2005 ; Ahn and Fedewa, 2011 ). Withdrawal of physical activity may result in irritability, restlessness, nervousness, and frustration as a result of a drop in endorphin levels. Although more studies are needed to specify the exact neurological pathways that mediate this relationship, it appears that the favorable impact of physical activity on the prevention and treatment of depression may be the result of adaptations in the central nervous system mediated in part by neurotropic factors that facilitate neurogenerative, neuroadaptive, and neuroprotective processes ( Dishman et al., 2006 ). It has been observed, for example, that chronic wheel running in rats results in immunological, neural, and cellular responses that mitigate several harmful consequences of acute exposure to stress ( Dishman et al., 2006 ). A recent study found that children who were more physically active produced less cortisol in response to stress, suggesting that physical activity promotes mental health by regulating the hormonal responses to stress ( Martikainen et al., 2013 ).

Psychological mechanisms that may explain why physical activity improves mental health include (1) distraction from unfavorable stimuli, (2) increase in self-efficacy, and (3) positive social interactions that can result from quality physical activity programming ( Peluso and de Andrade, 2005 ) (see also the discussion of psychosocial health above). The relative contribution of physiological and psychological mechanisms is unknown, but they likely interact. Poor physical health also can impair mood and mental function. Health-related quality of life improves with physical activity that increases physical functioning, thereby enhancing the sense of well-being ( McAuley and Rudolph, 1995 ; HHS, 2008 ).

Physical activity during childhood and adolescence may not only be important for its immediate benefits for mental health but also have implications for long-term mental health. Studies have shown a consistent effect of physical activity during adolescence on adult physical activity ( Hallal et al., 2006 ). Physical activity habits established in children may persist into adulthood, thereby continuing to confer mental health benefits throughout the life cycle. Furthermore, physical activity in childhood may impact adult mental health regardless of the activity's persistence ( Hallal et al., 2006 ).

Physical activity can improve mental health by decreasing and preventing conditions such as anxiety and depression, as well as improving mood and other aspects of well-being. Evidence suggests that the mental health benefits of physical activity can be experienced by all age groups, genders, and ethnicities. Moderate effect sizes have been observed among both youth and adults. Youth with the highest risk of mental illness may experience the most benefit. Although evidence is not adequate to determine the ideal regimen, aerobic and high-intensity physical activity are likely to confer the most benefit. It appears, moreover, that a variety of types of physical activity are effective in improving different aspects of mental health; therefore, a varied regimen including both aerobic activities and strength training may be the most effective. Frequent episodes of physical activity are optimal given the well-substantiated short-term effects of physical activity on mental health status. Although there are well-substantiated physiological bases for the impact of physical activity on mental health, physical activity programming that effectively enhances social interactions and self-efficacy also may improve mental health through these mechanisms. Quality physical activity programming also is critical to attract and engage youth of all skills level and to effectively reach those at highest risk.

In conclusion, frequently scheduled and well-designed opportunities for varied physical activity during the school day and a reduction in sedentary activity have the potential to improve students' mental health in ways that could improve their academic performance and behaviors in school.

Children's exercise capacity and the activities in which they can successfully engage change in a predictable way across developmental periods. For example, young children are active in short bursts, and their capacity for continuous activity increases as they grow and mature (see Figure 3-2 ). In adults and likely also adolescents, intermittent exercise has much the same benefit as continuous exercise when mode and energy expenditure are held constant. The health benefits of sporadic physical activity at younger ages are not well established. However, the well-documented short-term benefits of physical activity for some aspects of mental and cognitive health suggest that maximum benefit may be attained through frequent bouts of exercise throughout the day.

Changes in physical activity needs with increasing age of children and adolescents. SOURCE: Adapted from Malina, 1991. Reprinted with permission from Human Kinetics Publishers.

Children require frequent opportunities for practice to develop the skills and confidence that promote ongoing engagement in physical activity. Physical education curricula are structured to provide developmentally appropriate experiences that build the motor skills and self-efficacy that underlie lifelong participation in health-enhancing physical activity, and trained physical education specialists are uniquely qualified to deliver them (see Chapter 5 ). However, physical education usually is offered during a single session. Therefore, other opportunities for physical activity can supplement physical education by addressing the need for more frequent exercise during the day (see Chapter 6 ). In addition to the immediate benefits of short bouts of physical activity for learning and for mental health, developmentally appropriate physical activity during those times, along with the recommended time in physical education, can contribute to daily energy expenditure and help lessen the risk of excess weight gain and its comorbidities. Specific types of activities address specific health concerns. For example, vertical jumping activities contribute to energy expenditure for obesity prevention and also promote bone development (via the resulting ground reaction forces), potentially contributing to lower fracture risk. Other activities contribute to prevention of chronic disease. Since different types of physical activity contribute to distinct aspects of physical, mental, and psychosocial health, a varied regimen is likely to be most beneficial overall.

In sum, a comprehensive physical activity plan with physical education at the core, supplemented by other varied opportunities for and an environment supportive of physical activity throughout the day, would make an important contribution to children's health and development, thereby enhancing their readiness to learn.

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Cite this Page Committee on Physical Activity and Physical Education in the School Environment; Food and Nutrition Board; Institute of Medicine; Kohl HW III, Cook HD, editors. Educating the Student Body: Taking Physical Activity and Physical Education to School. Washington (DC): National Academies Press (US); 2013 Oct 30. 3, Physical Activity and Physical Education: Relationship to Growth, Development, and Health.
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What Is The Importance Of Physical Education?

June 30, 2022

Table of Content

Children can enjoy and be successful in a variety of physical activities with the help of a high-quality physical education curriculum. They gain a variety of abilities, including the capacity to successfully employ tactics, strategies, and compositional ideas. Teachers and students both should know the importance of physical education . While they are acting, they consider what they are doing, consider the circumstances, and come to decisions.

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Additionally, they evaluate their own and others’ performances and look for ways to make them better. As a result, students have the self-assurance to engage in a variety of physical activities and understand the importance of physical education comprehend the significance of leading healthy, active lifestyles.

Some of the importance of physical education is to improve your daily life

1. improve academic performance.

Studies have demonstrated that physical activity, including team sports, biking, swimming at the beach, and playground games, has positive effects on the brain and academic achievement. Children learn how to be motivated and productive, fit and healthy for life, as well as how to think creatively through physical education.

It has been demonstrated that participation in sports, physical education, and physical activity increases students’ sense of connection to their school and its objectives. The degree to which kids act socially responsible at school. A busy mind makes it easier to focus for longer periods of time and may also be beneficial for learning.

2. Develop Social Skills

Physical education teaches children the concept of teamwork, and being a team member provides them a feeling of identity. Children learn skills that open the door for positive interactions and relationships throughout life when physical education teachers exhibit prosocial behavior. They learn vital social and communication skills from this. It enables students to support others, collaborate with a variety of team members, and develop as team players.

3. Reduce Stress

They must finish their homework at home after spending several hours at school, which leaves them with little time for other activities. Students are also put under a lot of mental and physical stress because they spend so much time on their studies. Some of that stress and anxiety can be reduced by engaging in physical activity. Additionally, it supports emotional stability and toughness and also helps in health and physical education .

4. Self-improvement and character development

Team sports in a structured environment helps develop leadership and sportsmanship. Students are encouraged to respect themselves and their peers by taking on different responsibilities on a team and learning new talents. Additionally, it teaches kids to empathize with others and helps them get through tough times.

Earning praise from coaches or other players also helps to increase self-esteem. Teammate gestures like handshakes, pats on the back, and high-fives help to foster confidence and togetherness. As a result, kids become more confident in their skills and are motivated to advance in their chosen sport.

5. Increases focus and retention

Students who are entirely engaged in their studies will need more than one break each day. Physical education plays a role in this. When students engage in physical exercise in the classroom, they can break up the monotony and expend the surplus energy that is feeding their boredom and preventing them from paying attention in class.

6. Complete sleep

Planning the amount and timing of regular exercise is crucial rather than attempting to start a daily exercise routine all at once. Studies have looked into how a few weeks of moderate exercise can improve teens’ poor sleep quality and duration. However, it has been demonstrated that some teenagers’ sleep duration is reduced by intense activity during the same period.

Adults in good health who frequently exercise can sleep better. Regular, gentle exercise can improve sleep length, quality, and sleep onset time, while severe exercise can only slightly affect these factors.

7. Bring leadership quality and better communication

Every child has a propensity to influence others in some way. Members have a variety of backgrounds, attitudes, and experiences; some are outgoing and gregarious, while others are quiet and unassuming. Numerous effective leaders have been encouraged by mentors to hone their leadership skills .

While some people are born with leadership qualities, research indicates that anyone, including children, can acquire them given the right instruction and access to decision-making power. If you adhere to constructivism, you might assume that young people can develop their leadership abilities by applying what they already know to novel perspectives on the world.

The Final Thought

Students are more likely to engage in physical activities outside of school when they have better skills, stronger muscles, more bone density, and also a will to participate. Additionally, it enables kids to comprehend the positive effects of exercise and how good it may make them feel.

Classplus is one of the best teaching platforms where you can also be a physical education teacher and teach the Importance of Physical Education in the modern era . Classplus helps you in making your own app and helps you to grow. You can get more flexibility here to take your classes and get more recognized via online apps. Get your app in 60 sec and start educating the students. You can also sell your courses here. Take a chance.

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Why is Physical Education Important? Benefits of PE (Latest)

Education Important

Physical Education is Important for several reasons, as it has a wide range of benefits for individuals of all ages. Here are some of the key reasons why physical education is important:

Physical Health: Regular physical activity helps improve physical health by increasing cardiovascular fitness, building muscle strength and endurance, and maintaining a healthy weight. It also reduces the risk of various chronic diseases such as heart disease, diabetes, and obesity.
Mental Health: Physical education has a positive impact on mental health by reducing symptoms of anxiety and depression. It releases endorphins, which are natural mood lifters and help individuals cope with stress.
Motor Skills: Physical education programs help develop and refine motor skills such as coordination, balance, and agility. These skills are not only important for sports but also for daily activities and tasks.
Teamwork and Cooperation: Many physical education activities involve teamwork and cooperation, which teach important social skills like communication, problem-solving, and conflict resolution. Learning to work together in a physical context can translate to better collaboration in other areas of life.
Discipline and Goal Setting: Physical education encourages discipline and goal setting. Students learn the importance of setting goals, working toward them, and achieving success through effort and dedication.
Lifelong Fitness Habits: Physical education programs aim to instill a love for physical activity and fitness that lasts a lifetime. Exposing individuals to a variety of sports and activities helps them find activities they enjoy and are more likely to continue as adults.

More importance of PE…

Improved Academic Performance: Research has shown that regular physical activity can have a positive impact on academic performance. It can improve concentration, memory, and cognitive function.
Healthy Lifestyle Choices: Physical education can educate individuals about the importance of a healthy lifestyle, including nutrition and the dangers of substance abuse. It helps promote informed decision-making regarding health-related behaviors.
Prevention of Obesity: With the rising rates of childhood obesity, physical education plays a crucial role in preventing and addressing this issue. It promotes physical fitness and encourages healthy eating habits.
Socialization and Inclusivity: Physical education classes provide opportunities for socialization and inclusivity. Students interact with peers from diverse backgrounds and abilities, promoting tolerance and understanding.
Stress Relief: Physical activity is an effective way to relieve stress and improve mental well-being. Engaging in physical education can help students manage the pressures of school and life.
Overall Well-Being: Physical education contributes to an individual’s overall well-being by promoting a balanced and healthy lifestyle. It enhances the quality of life by keeping individuals physically and mentally fit.

In summary, physical education is important because it contributes to both physical and mental well-being, teaches essential life skills, and promotes a healthy, active lifestyle that can lead to a longer, happier, and more fulfilling life. It is an integral part of a comprehensive education that prepares individuals for a healthy and successful future.

Benefits Of Physical Education

Physical education (PE) offers a wide range of benefits for individuals of all ages. Here are some of the key benefits of physical education:

Physical Fitness: PE helps individuals improve their physical fitness by promoting regular physical activity. It enhances cardiovascular health, muscular strength, endurance, and flexibility.
Health Promotion: Regular participation in PE can reduce the risk of chronic diseases such as heart disease, diabetes, obesity, and certain types of cancer. It encourages a healthy lifestyle and promotes overall well-being.
Motor Skill Development: PE programs focus on developing and refining motor skills, including coordination, balance, agility, and fine motor skills. These skills are essential for various physical activities and daily tasks.
Mental Health: Physical activity in PE classes has a positive impact on mental health. It releases endorphins, which can improve mood and reduce symptoms of anxiety and depression.
Stress Reduction: Engaging in physical activity can help students and individuals manage stress more effectively. It provides a healthy outlet for pent-up energy and tension.
Improved Academic Performance: Research has shown that regular physical activity can lead to improved academic performance. It enhances cognitive function, concentration, and memory.
Social Skills: PE often involves team sports and cooperative activities, fostering the development of social skills such as communication, teamwork, leadership, and conflict resolution.
Discipline and Goal Setting: PE encourages discipline and goal setting. Students learn the importance of setting fitness goals, working toward them, and tracking progress.

Extra Benefits of PE…

Inclusivity: Good PE programs promote inclusivity by accommodating individuals with various abilities and skill levels. This helps create an inclusive and supportive learning environment.
Lifelong Fitness Habits: PE aims to instill a love for physical activity and fitness that lasts a lifetime. It exposes individuals to a variety of sports and activities, helping them find activities they enjoy and are more likely to continue as adults.
Body Confidence: Engaging in PE can improve body confidence and self-esteem. As individuals develop physical skills and fitness, they may gain a more positive self-image.
Healthy Lifestyle Education: PE can educate individuals about the importance of a healthy lifestyle, including nutrition, the dangers of substance abuse, and making informed decisions about their health.
Time Management: Participation in PE classes helps individuals learn how to manage their time effectively, as they must balance academic studies with physical activity.
Physical Literacy: PE teaches individuals the fundamentals of movement and physical literacy, ensuring they have the skills and knowledge needed to participate in a wide range of physical activities.
Fun and Enjoyment: PE classes can be enjoyable, encouraging students to view physical activity as a source of pleasure rather than a chore.
Community and School Spirit: Participation in team sports and group activities can foster a sense of community and school spirit, promoting a positive school culture.

Overall, Physical Education plays a crucial role in promoting physical and mental well-being, developing essential life skills, and encouraging a healthy and active lifestyle. It contributes to the holistic development of individuals and prepares them for a healthier and more successful future.

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What School Subjects Do You Need in High School?

The subjects you study in high school should allow you to graduate, but you’ll also want classes that will prepare you for college and for life as an adult.

Subjects Offered in High School
Subjects Needed to Graduate
Subjects for College Preparation

Picking high school courses is an exciting process. Core high school subjects like math, science, and language arts are required, but a range of others can be selected. Finally being given more of a choice in what a student studies can be freeing, but also may feel overwhelming, confusing, or stressful.

What courses are best? There's no one right path. First, consider what is needed to graduate. Then, take a look at your options.

Parents and teens can work together to choose school subjects that not only engage their interests but also have their future plans and goals in mind.

For example, students who want to go to college may be required to take more years of a foreign language or other classes required by the schools they are interested in. A student who is interested in pursuing a career in construction may want to take an industrial arts class.

Read on to learn more about selecting courses in high school.

Parents / Nusha Ashjaee

What School Subjects Are Offered in High School?

Most high schools offer the same basic school subjects: Math, language arts, foreign language, science, social studies, health, and physical education (PE).

However, the exact courses may vary dramatically from school to school. Different high schools—even within the same district—often have different course offerings or special programs. If possible, choose the local high school that provides the programs and classes that best suit your needs and passions.

Below is a list of the most common school subjects. However, individual schools may offer a range of specialized classes, such as mindfulness or engineering.

High School Subjects

Literature or Language Arts
Speech and Debate
Writing or Composition
Trigonometry or Calculus
Biology (typically has advanced class options)
Chemistry (typically has advanced class options)
Earth or Space Sciences
Physics (typically has advanced class options)
US Government
World History
Foreign Language, such as Spanish, French, Japanese, Chinese, Arabic, and German
Physical Education and Health
Arts, such as Music, Photography, Drawing, or Ceramics
Computer Applications, Graphic Design, or Web Design
Cooking and other life skills
Physical Education
Trade field studies such as Auto Mechanics, Woodworking, or Nursing
Personal Finance

School Subjects You Need to Graduate

Ideally, teens should start high school with a basic plan of the classes they will need to take to graduate. Every state has different requirements for obtaining a high school diploma, and each school varies greatly in what it offers to give kids a chance to fulfill them. Different schools also vary in the number of classes students take each year.

The school's guidance department can help students understand the graduation requirements and how their coursework aligns with them.

English language arts

Studying the English language and literature is an important part of high school for every student, regardless of their post-school plans. In addition to studying important pieces of literature, English classes teach teens about writing, reading, and speaking.

Most states require four years of English or language arts classes. Colleges require four years of English for admission. The main English classes in high school include:

Mathematics

In high school, students dig into several different types of math . Algebra and geometry are required at most high schools, and students may choose to take advanced math classes if they are offered.

Most states require three or four years of math coursework in high school. The main math classes in high school include:

Basic life sciences (biology) and physical sciences (chemistry and physics) are required at most high schools. These classes often include lab components that allow students to perform hands-on experiments.

Most states require two to three years of science coursework in high school. These may include:

Biology (typically has advanced class options)
Chemistry (typically has advanced class options)
Earth or Space sciences

Social studies and history

Understanding the past and how the world works is important for young adults. In high school, students will study history and government and learn about how social studies affects their lives.

Most states require three to four years of social studies coursework in high school, including:

Foreign languages

Learning a second language is important in today's global world. While many high schools offer foreign language courses, only 11 states require students to take a foreign language course.

High school students can fill these requirements by learning the basics of at least one foreign language. They may also be able to choose to take advanced classes to learn more.

Common languages offered in high school include:

Mandarin Chinese

Other possible language offerings include Russian, Latin, American Sign Language, Arabic, and German.

Physical education and health

Physical education and health classes can teach high schoolers how to care for their bodies' fitness, health, and nutritional needs. These courses often touch on the following:

Mental health
Sexual health
Making healthy choices about drugs, alcohol, and nicotine.

Many states require at least one unit of PE and health to graduate. Other states offer these subjects as electives.

School Subjects for College Preparation

Students planning to go to college should consider how colleges will look at their courses during the application process. Grade point average (GPA) is important, but coursework should also demonstrate academic rigor.

When planning, it can be helpful to balance standard high school courses with some that are more challenging. Additionally, students can do this—and even get a head start on college—by taking advanced placement (AP) or college-level classes.

AP classes are more rigorous courses that teach subjects at an introductory college level. Some of the most common AP courses that are available include:

Calculus AB
English Literature
African American Studies

Students who take AP classes have the option to take an AP test in the spring. If they get a certain score, they can get credit for the course at many colleges.

College credit courses

Many high schools offer opportunities to gain college credit through various programs. Your child's academic advisor, teachers, or counseling department can inform them about such offerings.

These may be online or in-person classes through programs offered by colleges and universities, and a professor or a high school teacher may teach them. Dual-credit programs allow students to fulfill their high school requirements while obtaining some college credits free of charge.

School Subject Electives

In addition to the basic classes, there are usually plenty of opportunities to take electives in various areas of study. These can not only broaden a student's academic knowledge but also teach them valuable life skills and inspire their career aspirations .

In some cases, a student may be given the freedom to choose one class from a select group of options required in the school's curriculum. In others, a student may have room in their schedule to choose to study something simply based on their interests and goals.

Examples of elective classes may include:

Arts, such as music, photography, fashion design, painting, theater, dance, or ceramics
Computer applications, graphic design, or web design
Student government
Forensic science
Physical education
Sports medicine
Trade field studies such as auto mechanics, welding, or nursing
Personal finance or business

Students on a vocational track may be able to gain some hands-on learning in fields such as metalworks and woodworking. Many schools even offer the opportunity to gain certificates or licenses that will help them in their future careers .

Key Takeaways

Choosing high school classes requires planning both as a student enters school and throughout their high school experience. The right classes are challenging and engaging but not unrealistically rigorous or overwhelming.

An ideal schedule can help a student succeed, enjoy learning, and have a good academic experience while preparing them for their future plans , whatever they may be. Have your teen set up a meeting with their school counselor if they need any help.

The association between neighbourhoods and educational achievement, a systematic review and meta-analysis . J Hous Built Environ . 2016.

50-state comparison . Education Commission of the States . 2019.

High school classes required for college admission . National Association for College Admission Counseling . n.d.

The national K-16 foreign language enrollment survey report . American Councils for International Education . 2017.

Program summary report . College Board. 2019.

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The Benefits of Interprofessional Education in Physical Therapy

group of people sit around an older woman in a PT gym

Interprofessional education (IPE) is increasingly recognized as a critical component of comprehensive healthcare education, including the field of physical therapy. Interprofessional education involves learning from, with, and about other healthcare disciplines to cultivate collaborative practice and enhance patient care. By bringing together students from various healthcare professions, interprofessional education fosters a team-based approach to healthcare, preparing students to become part of an interprofessional team.

Enhancing Collaborative Skills

One of the primary benefits of interprofessional education is its role in enhancing collaborative skills among future healthcare providers. Through IPE, physical therapy students learn to:

Communicate Effectively : Develop and refine communication skills essential for clear, concise information exchange among team members.
Understand Roles: Gain an understanding of the roles, responsibilities, and expertise of various healthcare professionals.
Resolve Conflicts : Learn strategies for resolving conflicts constructively, a necessary skill in high-stakes healthcare environments.
Foster a team approach : Learn a patient-centered approach working as a team rather than in silos towards a common goal of helping patients.

Improving Patient Care

Interprofessional education directly contributes to improved patient care outcomes. By learning to work effectively as part of a team, physical therapy students are better equipped to contribute to:

Holistic Patient Assessment : Collaborate with professionals from different disciplines to assess patients' needs comprehensively.
Coordinated Care Plans : Participate in the creation of coordinated, interdisciplinary care plans that address the complex needs of patients.
Enhanced Patient Safety : Reduce errors through improved communication and a shared understanding of treatment goals.

Promoting Professional Development

Interprofessional education also plays a significant role in the professional development of physical therapy students, fostering:

A Broader Perspective : Exposure to the viewpoints and expertise of other healthcare disciplines enriches students’ understanding of healthcare.
Lifelong Learning : Cultivate a commitment to continued learning and collaboration beyond formal education.
Adaptability : Prepare students for the dynamic nature of healthcare settings, where teamwork and flexibility are paramount.

Fostering a Culture of Respect

An important outcome of interprofessional education is the fostering of mutual respect among future healthcare professionals. IPE helps physical therapy students:

Appreciate Diverse Expertise : Recognize and value the unique contributions of various healthcare disciplines.
Build Professional Relationships : Establish a network of professional contacts across different healthcare fields.
Promote Inclusivity : Encourage an inclusive approach to patient care that leverages the strengths of each team member.

Meeting the Demands of Modern Healthcare

Interprofessional education aligns with the evolving demands of the healthcare industry by:

Addressing Complexity : Preparing students to navigate the complexities of modern healthcare systems and patient needs.
Emphasizing Prevention : Highlighting the importance of collaborative efforts in preventive care and public health initiatives.
Adapting to Policy Changes : Educating students about the implications of healthcare policies and the importance of interdisciplinary advocacy.

MGH Institute of Health Professions: Leading in Interprofessional Education

The MGH Institute of Health Professions, a graduate school affiliate of Mass General Brigham, exemplifies excellence in interprofessional education within its physical therapy program . By integrating IPE throughout its curriculum, the Institute ensures that its graduates are not only proficient in their discipline but also adept at working within interprofessional teams. Highlights of the MGH IHP's PT program include:

Interprofessional Courses : Dedicated coursework in interprofessional collaborative practice where DPT students collaborate with students from other disciplines to learn various aspects of working in an interprofessional team.
Clinical Rotations : Participating in clinical experiences embedded within the Mass General Brigham hospitals where students observe and engage in interdisciplinary interactions that emphasize interprofessional collaboration.
Simulation Learning : Utilizing state-of-the-art simulation labs to practice interprofessional patient care scenarios.

Interprofessional education represents a shift in healthcare education, one that is especially beneficial in the field of physical therapy. By fostering collaboration, communication, and mutual respect among future healthcare providers, IPE ensures that physical therapy graduates are well-prepared to meet the demands of modern healthcare environments.

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Write a Letter to Your Friend Making Aware of the Importance of Sports in One’s Life: Check Samples

Updated on
May 22, 2024

Write a Letter to Your Friend Making Aware of the Importance of Sports in One's Life

Sports are very important in life. They not only make us physically fit but also promote a healthy mindset. Not only us, but we should motivate our friends to do it. Hence, in this blog, we are providing samples of how to write a letter to your friend, making them aware of the importance of sports in one’s life. After the samples, you will also find the format of the letter. You can also enhance the art of writing letters with these 199+ Letter Writing topics for everyone . Let us explore this blog.

Table of Contents

1 Sample 1: Write a Letter to Your Friend Making Aware of the Importance of Sports in One’s Life
2 Sample 2: Write a Letter to Your Friend Making Aware of the Importance of Sports in One’s Life
3 Format of How to Write a Letter to Your Friend Making Aware of the Importance of Sports in One’s Life
4 FAQs

Sample 1: Write a Letter to Your Friend Making Aware of the Importance of Sports in One’s Life

Also Read: Write a Letter to Your Friend Telling Him About Your School: Download Samples

Sample 2: Write a Letter to Your Friend Making Aware of the Importance of Sports in One’s Life

Also Read : Write a Letter to Your Pen Friend Living in Another Country: Check Samples and Format

Format of How to Write a Letter to Your Friend Making Aware of the Importance of Sports in One’s Life

Download the Format of Informal Letter from Here!!

Also Read : Write a Letter to Your Friend Who Has Failed in Examination: Check Samples and Format

Ans: Start the letter with a polite tone. Then mention the importance of sports. Include instances from your own life if possible. Mention how sports improve physical and mental health. Then conclude the letter on a polite note.

Ans: A letter to a friend can be in a polite and warm tone. Start by asking how they are, and then by telling them how you are. Keep the letter conversational. Cover what you want to entirely in the letter, then conclude it with a “take care,” etc.

Ans: You can end the letter to your friend with “talk to you soon,” “see you soon,” etc.

Check out more letter-writing topics here:

We hope the above-listed sample letters will improve your letter-writing skills. For more such interesting topics, visit our Letter Writing page and follow Leverage Edu.

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About Adverse Childhood Experiences
Risk and Protective Factors
Program: Essentials for Childhood: Preventing Adverse Childhood Experiences through Data to Action
Adverse childhood experiences can have long-term impacts on health, opportunity and well-being.
Adverse childhood experiences are common and some groups experience them more than others.

diverse group of children lying on each other in a park

What are adverse childhood experiences?

Adverse childhood experiences, or ACEs, are potentially traumatic events that occur in childhood (0-17 years). Examples include: 1

Experiencing violence, abuse, or neglect.
Witnessing violence in the home or community.
Having a family member attempt or die by suicide.

Also included are aspects of the child’s environment that can undermine their sense of safety, stability, and bonding. Examples can include growing up in a household with: 1

Substance use problems.
Mental health problems.
Instability due to parental separation.
Instability due to household members being in jail or prison.

The examples above are not a complete list of adverse experiences. Many other traumatic experiences could impact health and well-being. This can include not having enough food to eat, experiencing homelessness or unstable housing, or experiencing discrimination. 2 3 4 5 6

Quick facts and stats

ACEs are common. About 64% of adults in the United States reported they had experienced at least one type of ACE before age 18. Nearly one in six (17.3%) adults reported they had experienced four or more types of ACEs. 7

Preventing ACEs could potentially reduce many health conditions. Estimates show up to 1.9 million heart disease cases and 21 million depression cases potentially could have been avoided by preventing ACEs. 1

Some people are at greater risk of experiencing one or more ACEs than others. While all children are at risk of ACEs, numerous studies show inequities in such experiences. These inequalities are linked to the historical, social, and economic environments in which some families live. 5 6 ACEs were highest among females, non-Hispanic American Indian or Alaska Native adults, and adults who are unemployed or unable to work. 7

ACEs are costly. ACEs-related health consequences cost an estimated economic burden of $748 billion annually in Bermuda, Canada, and the United States. 8

ACEs can have lasting effects on health and well-being in childhood and life opportunities well into adulthood. 9 Life opportunities include things like education and job potential. These experiences can increase the risks of injury, sexually transmitted infections, and involvement in sex trafficking. They can also increase risks for maternal and child health problems including teen pregnancy, pregnancy complications, and fetal death. Also included are a range of chronic diseases and leading causes of death, such as cancer, diabetes, heart disease, and suicide. 1 10 11 12 13 14 15 16 17

ACEs and associated social determinants of health, such as living in under-resourced or racially segregated neighborhoods, can cause toxic stress. Toxic stress, or extended or prolonged stress, from ACEs can negatively affect children’s brain development, immune systems, and stress-response systems. These changes can affect children’s attention, decision-making, and learning. 18

Children growing up with toxic stress may have difficulty forming healthy and stable relationships. They may also have unstable work histories as adults and struggle with finances, jobs, and depression throughout life. 18 These effects can also be passed on to their own children. 19 20 21 Some children may face further exposure to toxic stress from historical and ongoing traumas. These historical and ongoing traumas refer to experiences of racial discrimination or the impacts of poverty resulting from limited educational and economic opportunities. 1 6

Adverse childhood experiences can be prevented. Certain factors may increase or decrease the risk of experiencing adverse childhood experiences.

Preventing adverse childhood experiences requires understanding and addressing the factors that put people at risk for or protect them from violence.

Creating safe, stable, nurturing relationships and environments for all children can prevent ACEs and help all children reach their full potential. We all have a role to play.

Merrick MT, Ford DC, Ports KA, et al. Vital Signs: Estimated Proportion of Adult Health Problems Attributable to Adverse Childhood Experiences and Implications for Prevention — 25 States, 2015–2017. MMWR Morb Mortal Wkly Rep 2019;68:999-1005. DOI: http://dx.doi.org/10.15585/mmwr.mm6844e1 .
Cain KS, Meyer SC, Cummer E, Patel KK, Casacchia NJ, Montez K, Palakshappa D, Brown CL. Association of Food Insecurity with Mental Health Outcomes in Parents and Children. Science Direct. 2022; 22:7; 1105-1114. DOI: https://doi.org/10.1016/j.acap.2022.04.010 .
Smith-Grant J, Kilmer G, Brener N, Robin L, Underwood M. Risk Behaviors and Experiences Among Youth Experiencing Homelessness—Youth Risk Behavior Survey, 23 U.S. States and 11 Local School Districts. Journal of Community Health. 2022; 47: 324-333.
Experiencing discrimination: Early Childhood Adversity, Toxic Stress, and the Impacts of Racism on the Foundations of Health | Annual Review of Public Health https://doi.org/10.1146/annurev-publhealth-090419-101940 .
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Adverse Childhood Experiences (ACEs)

ACEs can have a tremendous impact on lifelong health and opportunity. CDC works to understand ACEs and prevent them.

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PE Poster: Why Physical Education?

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ADAPTED PHYSICAL EDUCATION AND ITS IMPORTANCE
Health: Why is Physical Activity & Fitness Important?

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Physical education for healthier, happier, longer and more ...
Physical education for healthier, happier, longer and more productive living. The time children and adults all over the world spend engaging in physical activity is decreasing with dire consequences on their health, life expectancy, and ability to perform in the classroom, in society and at work. In a new publication, Quality Physical Education ...
Physical Education
Physical education is the foundation of a Comprehensive School Physical Activity Program. 1, 2 It is an academic subject characterized by a planned, sequential K-12 curriculum (course of study) that is based on the national standards for physical education. 2-4 Physical education provides cognitive content and instruction designed to develop motor skills, knowledge, and behaviors for ...
PDF What is physical education? What's happening currently?
Students that attend physical education are: Approximately 2 - 3 times more likely to be active outside of school.5. Almost twice as likely to continue to be active to a healthy level in adulthood.5. *Doing any kind of physical activity that increased their heart rate and made them breathe hard some of the time during the 7 days before the survey.
Physical Activity and Physical Education: Relationship to Growth
The behaviors and traits of today's children, along with their genetics, are determinants of their growth and development; their physical, mental, and psychosocial health; and their physical, cognitive, and academic performance.Technological advances of modern society have contributed to a sedentary lifestyle that has changed the phenotype of children from that of 20 years ago.
Why Physical Education Is Important
You already know that physical activity is an important part of your child's health. But the benefits of physical education in schools go beyond the advantages of physical activity. Read on for some of the ways that physical education can improve your child's health, happiness and overall well-being. Physical Education Explained Physical education, or PE, […]
PE can do much more than keep children fit
Physical Education (PE) is ideally placed to support children's all-round development. As well as developing physical skills, PE teaches children intellectual skills, helps them navigate complex ...
Why PE matters for student academics and wellness right now
Physical education as a discipline has long fought to be taken as seriously as its academic counterparts. Even before the pandemic, fewer than half the states set any minimum amount of time for students to participate in physical education, according to the Society of Health and Physical Educators (SHAPE), which represents PE and health ...
Why is Physical Education So Important?
The benefits of physical education in schools are far-reaching, including both increased student physical health and better academic performance. Physical education is more than just running around a track or kicking a ball. It teaches children key life skills alongside improving their health and wellbeing. Obesity continues to rocket across ...
Physical Health and Education: A Life-Long Journey
Physical health and education are foundational to well-being across all stages of life. From early childhood through to the later years, the benefits of maintaining an active lifestyle and continual learning about health are vast and well-documented. Despite this, many view physical education as a priority only during school years, neglecting ...
Why is physical activity so important for health and well-being?
Here are some other benefits you may get with regular physical activity: Helps you quit smoking and stay tobacco-free. Boosts your energy level so you can get more done. Helps you manage stress and tension. Promotes a positive attitude and outlook. Helps you fall asleep faster and sleep more soundly.
What is the impact of physical education on students? Facts on Education
The term quality physical education is used to describe programs that are catered to a student's age, skill level, culture and unique needs. They include 90 minutes of physical activity per week, fostering students' well-being and improving their academic success. However, instructional time for quality phys-ed programs around the world are ...
Physical Education is just as important as any other school subject
Physical activity is vitally important for health, but PE at school can run the risk of putting children off exercise for life. shutterstock. Physical Education (PE) is often viewed as a marginal ...
What are the 10 Importance of Physical Education?
In this article, we will discuss the 10 most important benefits of physical education, including improved physical health, increased focus and concentration, better social skills, enhanced coordination and balance, improved mental health, and more. Read on to learn why physical education is so important! Table of Contents show. 1.
Real-Life Benefits of Exercise and Physical Activity
Physical activity can help: Reduce feelings of depression and stress, while improving your mood and overall emotional well-being. Increase your energy level. Improve sleep. Empower you to feel more in control. In addition, exercise and physical activity may possibly improve or maintain some aspects of cognitive function, such as your ability to ...
Physical Education and Physical Activity
Physical Education and Physical Activity. Schools are in a unique position to help students attain the nationally recommended 60 minutes or more of moderate-to-vigorous physical activity daily. 1 Regular physical activity in childhood and adolescence is important for promoting lifelong health and well-being and preventing various health ...
10 Reasons Why Physical Education is Important
5. Improves Attention Span, Self-Esteem, and Body Image. One of the most important reasons for physical education is that it has been proven to improve a whole range of skills, from increasing attention span to improving self-esteem, and from enhancing body image to helping develop social skills.
PDF Need and importance of physical education for school students
Builds self-esteem; and The purpose of physical education is to instill in students, at an early age, the value of self-preservation and choosing a lifestyle that is good for both the mind and body. Most physical education programs are holistic. This paper primarily aims to ―give an insight into the health benefits of physical education ...
Exercise: 7 benefits of regular physical activity
Check out these seven ways that exercise can lead to a happier, healthier you. 1. Exercise controls weight. Exercise can help prevent excess weight gain or help you keep off lost weight. When you take part in physical activity, you burn calories. The more intense the activity, the more calories you burn. Regular trips to the gym are great, but ...
Physical Activity and Physical Education: Relationship to Growth
Evidence for both direct and indirect health effects of physical activity has been reported (Hallal et al., 2006), and the need for ongoing participation in physical activity to stimulate and maintain the chronic adaptations that underlie those benefits is well documented.To understand the relationship of physical activity and aerobic fitness to health during childhood, it is important first ...
The Importance of Physical Education in Schools
Importance of Physical Education Classes. Physical education is an important part of a student's education because it helps them to stay healthy and learn teamwork skills. In addition, physical education can help students maintain a healthy weight and develop lifelong physical activity habits. Schools need to provide physical education ...
What Is The Importance Of Physical Education?
Some of the importance of physical education is to improve your daily life. 1. Improve academic performance. Studies have demonstrated that physical activity, including team sports, biking, swimming at the beach, and playground games, has positive effects on the brain and academic achievement. Children learn how to be motivated and productive ...
Why is Physical Education Important? Benefits of PE (Latest)
Stress Relief: Physical activity is an effective way to relieve stress and improve mental well-being. Engaging in physical education can help students manage the pressures of school and life. Overall Well-Being: Physical education contributes to an individual's overall well-being by promoting a balanced and healthy lifestyle. It enhances the ...
PDF What is physical education? What's happening currently?
Physical education defined: • • • A K-12 academic subject that provides standards-based curricula and instruction. Part of a well-rounded education. Designed to develop the knowledge and behaviors for physical activity, physical fitness, and motor skills in students. Physically active students:
Developmentally Appropriate Physical Activities in the Classroom to
Physical activity programs during the school day prevent students from being sedentary. One of the environments where students spend the most time during the school day is the classroom. The purpose of this article is to provide suggestions for how students can participate in physical activity during the school day in the classroom environment.
What School Subjects Do Teens Need in High School?
Electives. Picking high school courses is an exciting process. Core high school subjects like math, science, and language arts are required, but a range of others can be selected. Finally being ...
The Benefits of Interprofessional Education in Physical Therapy
An important outcome of interprofessional education is the fostering of mutual respect among future healthcare professionals. IPE helps physical therapy students: Appreciate Diverse Expertise: Recognize and value the unique contributions of various healthcare disciplines. Build Professional Relationships: Establish a network of professional ...
School-Based Physical Activity Improves Healthy and Supportive School
School leaders can. Recognize the value of physical education and physical activity for health, enjoyment, challenge, self-expression, and social interaction. 4 Support physical activity integration in the classroom to reinforce what is taught in physical education and give students a chance to practice their new knowledge and skills.
Write a Letter to Your Friend Making Aware of the Importance of Sports
Sports are very important in life. They not only make us physically fit but also promote a healthy mindset. Not only us, but we should motivate our friends to do it.
About Physical Activity
Key points. Physical activity is one of the best things people can do to improve their health. Physical activity is vital for healthy aging. It can help reduce the chances of getting some chronic diseases and prevent early deaths. CDC works with state and local organizations to increase physical activity.
About Adverse Childhood Experiences
Outcomes. ACEs can have lasting effects on health and well-being in childhood and life opportunities well into adulthood. 9 Life opportunities include things like education and job potential. These experiences can increase the risks of injury, sexually transmitted infections, and involvement in sex trafficking.