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Subgroup Effects
Although studies frequently fail to report the age of participants, data 
on the effects of physical activity on mental health are strongest for adults 
participating in high-intensity physical activity (Ahn and Fedewa, 2011). 
However, evidence relating physical activity to various measures of mental 
health has shown consistent, significant effects on individuals aged 11-20. 
A large prospective study found that physical activity was inversely associ-
ated with depression in early adolescence (Hasselstrom et al., 2002; Hallal 

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Educating the Student Body: Taking Physical Activity and Physical Education to School
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