Physical inactivity is a key determinant of health outcomes across the life span. A lack of activity increases the risk of heart disease, colon and breast cancer, diabetes mellitus, hypertension, osteoporosis, anxiety and depression, and other diseases. Recent studies have found that in terms of mortality, the global population health burden of physical inactivity approaches that of cigarette smoking and obesity. Indeed, the prevalence of physical inactivity, along with this substantial associated disease risk, has been described as a pandemic.
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. Clearly, the earlier in life this important health behavior can be ingrained, the greater the impact will be on life-long 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. The evidence base summarized supports the need to place greater emphasis on physical activity and physical education for children and adolescents, particularly on the role schools can play in helping youth meet physical activity guidelines.