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Educating the Student Body
Cardiovascular mortality by hours per week of vigorous- or moderate-
intensity physical activity and hours per day of television viewing.
SOURCE: Matthews et al., 2012. Reprinted with permission.
The health impact of sedentary-intensity physical activity among chil-
dren and adolescents is likely the same. A qualitative review of 232 
studies found a dose-response relationship between more sedentary 
behavior and unfavorable health outcomes, including unfavorable body 
composition, decreased fitness, lower scores for self-esteem and pro-
social behavior, and decreased academic achievement (Tremblay et al.,