for incidental physical activity also have declined for children and adolescents, as they have for adults, as the result of such factors as increased reliance on nonactive transportation, automation of activities of daily living, and greater opportunities for sedentary behavior. In addition, significant disparities in physical activity exist across racial/ethnic and socioeconomic lines (see Chapter 2).
The prevalence and health impacts of physical inactivity, together with evidence indicating its susceptibility to change, have resulted in calls for action aimed at increasing physical activity across the life span. A common belief is that, the earlier in life this important health behavior can be ingrained, the greater the impact will be on lifelong health. The question becomes, then, how physical activity among children and adolescents can be increased feasibly, effectively, and sustainably to improve their health, both acutely and throughout life. A recent report of the Institute of Medicine (IOM), Accelerating Progress in Obesity Prevention: Solving the Weight of the Nation, singles out schools as “a focal point for obesity prevention among children and adolescents,” stating: “Children spend up to half their waking hours in school. In an increasingly sedentary world, schools therefore provide the best opportunity for a population-based approach for increasing physical activity among the nation’s youth” (IOM, 2012, p. 333).
Given the importance of physical activity to health in youth and increasing attention to its role in educational performance, coupled with the potential of schools to provide opportunities to be physically active, a 14-member ad hoc committee of the IOM was convened and charged to review the current status of physical activity and physical education in the school environment. The committee was also tasked with reviewing influences of physical activity and physical education on the short- and long-term physical health, cognition and brain health, and psychosocial health and development of children and adolescents. The committee was asked to make recommendations, as appropriate, regarding approaches for strengthening and improving programs and policies for physical activity and physical education in the school environment, including before, during, and after school. In doing so, the committee was expected to review the current status of physical activity and physical education in the school environment; review evidence on the relationship between physical activity, physical education, or physical fitness and physical, cognitive and brain, and psychosocial health and development; within a life-stage framework, consider the role of physical activity– and physical education–related programs and policies in the school environment in contributing to short- and