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Educating the Student Body
for short-term training response in young adults (Simons-Morton et al., 
1988), assumed that benefits were derived only from vigorous physical 
activity. By the mid-1990s, consensus had been reached that health ben-
efits accrued from moderate-intensity physical activity as well, and the 
recommended dose was expanded to include either the dose of vigorous 
physical activity previously recommended or a dose of 30 min or more 
per day of moderate-intensity physical activity on 5 or more days per 
week (Pate et al., 1995; HHS, 1996). The dose of vigorous-intensity activ-
ity and the dose of moderate-intensity activity could be accumulated in 
segments as short as 8-10 min in length.
In 2005 a panel convened by the Centers for Disease Control and 
Prevention specifically to consider the physical activity needs of children 
and adolescents (aged 6-18) recommended that “school-aged youth 
should participate daily in 60 minutes or more of vigorous- or moderate-
intensity physical activity that is developmentally appropriate, enjoyable, 
and involves a variety of activities” (Strong et al., 2005, p. 736). The 2008 
report of the Physical Activity Guidelines Advisory Committee, noting a 
direct relationship between the volume of physical activity in youth and 
cardiorespiratory fitness, muscular strength, less adiposity among youth 
of normal weight, cardiovascular and metabolic health, bone mineral 
content and density, and several mental health outcomes, reiterated the 
value of 60 minutes or more of vigorous- or moderate-intensity physi-
cal activity per day for important health benefits (PAGAC, 2008). The 
committee further commented that weekly activity should include some 
vigorous activity on at least 3 days and some activities to strengthen 
muscles and bones.