A study of sixth-graders found that vigorous physical activity improved their grades.
While children in regular physical education classes didn't do any better than sedentary children, those who skateboarded or played organized soccer or football at least three times a week had grades 10 percent higher in math, science, English and social studies.
"Considering all the factors that go into what determines students' grades in school, a 10 percent increase by the most physically active kids is huge," said researcher Jim Pivarnik of Michigan State University.
The study monitored 200 students over a full academic year. For one semester half of the students took the general physical education class offered by the school, while the other half took part in a non-physical education course. Halfway through the school year they switched.
"We were expecting to find that students enrolled in PE would have better grades because of the opportunity to be active during the school day. But enrollment in PE alone did not influence grades," said study leader Dawn Podulka Coe of Grand Valley State University.
Is there a message here for schools?
"If kids have PE every day, is it going to hurt grades? The answer is no," Pivarnik said. "But, maybe if we pump up the volume a little bit, if they are a little more vigorously active, it might make a difference."
The research is published in the August issue of Medicine & Science in Sports & Exercise, the journal of the American College of Sports Medicine.
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