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Educating the Student Body
for incidental physical activity also have declined for children and adoles-
cents, as they have for adults, as the result of such factors as increased reli-
ance 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 com-
mon belief is that, the earlier in life this important health behavior can 
be ingrained, the greater the impact will be on lifelong health. The ques-
tion 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).