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Educating the Student Body
for adults in the workplace, for example, and many schools are seeking 
creative ways to integrate light physical activity into traditionally sedentary 
schoolwork. Such efforts are important given the amount of sedentary time 
entailed in schoolwork. In Australia, for example, 42 percent of nonscreen 
sedentary time is school related (Olds et al., 2010). 
Such efforts to address nonrecreational sedentarism are just emerging, 
and much research and innovation are needed to move these efforts for-
ward. On the other hand, significant research already exists on decreasing 
recreational sedentarism, especially among children, to treat or prevent 
obesity. Today, 46 percent of U.S. children aged 6-11 fail to meet the recom-
mendation of less than 2 hours of recreational sedentarism (screen time) per 
day (Fakhouri et al., 2013). In addition to the nonrecreational sedentarism 
that occurs while children sit to perform schoolwork, significant recre-
ational sedentarism takes place on the way to school and in school during 
breaks, recess, lunch, and after-school programs. Data are not available on 
the extent to which recreational sedentarism occurs on school grounds and 
on whether recreational sedentarism in school should be an important pub-
lic health target as it already is outside of school. What is known, however, 
is that “eight- to eighteen-year-olds spend more time with media than in any 
other activity besides (maybe) sleeping—an average of more than 7½ hours 
a day, seven days a week” (Rideout et al., 2010, p. 1).
One of the lessons of pediatric obesity research is that behavioral 
approaches designed to increase physical activity are different from those 
designed to decrease recreational sedentarism and have different effects 
on behavior and health. Using behavioral economic theory, Epstein and 
colleagues (1995) demonstrated that monitoring children and encouraging 
them to decrease recreational sedentarism was more successful in treating 
obesity than either promoting physical activity or targeting both physi-
cal activity and sedentarism at the same time. Furthermore, the children 
randomized to the intervention targeting only sedentarism increased their 
enjoyment of vigorous- or moderate-intensity physical activity, while enjoy-
ment of moderate-intensity physical activity decreased among those ran-
domized to physical activity promotion; changes in enjoyment among those 
in the combined intervention group were between those in the other two 
groups. The importance of targeting a decrease in sedentarism was further 
highlighted when Robinson (1999) published the first successful school-
based obesity prevention intervention that targeted only sedentarism, 
with no behavioral intervention focused on physical activity promotion 
or dietary changes. Since then, several randomized trials have confirmed 
the causal link between recreational sedentarism and childhood obesity 
(Tremblay et al., 2011). Despite this evidence, however, the approach of 
specifically targeting sedentarism has received only limited attention. While 
academic research has focused on using school as a setting in which to teach 

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Educating the Student Body: Taking Physical Activity and Physical Education to School
Approaches to Physical Activity in Schools
 
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students how to decrease sedentarism outside of school, this approach has 
not translated into widespread policies or curricula. Such efforts may be