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Educating the Student Body
The purpose of this chapter is to describe the evidence supporting these 
general statements about the status and trends of the physical activity behav-
iors of school-age children and adolescents, as well as the school- related 
policies and practices that help determine those behaviors. Description of 
the status and trends of physical activity behaviors of youth requires, along 
the way, some discussion about the behaviors themselves, how they are mea-
sured, and how the current recommendations came into being.