Exercise leads to better school performance: Review

By Dr. Ananya Mandal, MDJan 4 2012

A review of earlier studies has shown that academic excellence in children could be linked to how physically active they are. Writing in Archives of Pediatrics & Adolescent Medicine, researchers said they found strong evidence of a link between exercise and academic performance. The review looked at 14 studies involving more than 12,000 children.

Dr Amika Singh and colleagues from VU University Medical Center in Amsterdam, were prompted to look at the relationship between physical activity and academic performance because of concerns that pressure to improve children's school marks could mean they spend more time in the classroom and less time doing physical activity. So the authors identified 10 observational and four interventional studies for review. Twelve of the studies were conducted in the United States, one in Canada and one in South Africa. Sample sizes ranged from 53 to about 12,000 participants between the ages of six and 18 years. The period of follow-up varied between eight weeks and more than five years. Two of the studies reviewed were rated as being of high quality, the study says.

Researchers said they found strong evidence of a “significant positive relationship” between physical activity and academic performance using those two studies as evidence. The study said this could be because exercise helps cognition by increasing blood and oxygen flow to the brain. Physical activity could also reduce stress and improve mood, making children more likely to behave in the classroom.

Dr Singh said, “Children who learn to participate in sport also learn to obey rules. This may mean they are more disciplined and able to concentrate better during lessons.” The authors add that more studies examining the exact relationship between physical activity and academic performance were needed.

“People always ask, 'How much exercise do I need to do to get an A?' We don't know that but we would like to find out,” said Dr Singh. “Children should be active for at least one hour a day, for health reasons. But we also need to look at other things, like what kind of activities they should do, when they should do them and for how long.”

According to the Centers for Disease Control, students should have about one hour of physical activity every day to remain healthy; only 18% of high school students met this requirement in the week prior to a 2009 survey and 23% had not exercised at all during that period. The argument for reducing the amount of school time devoted to physical education is based on the fact that standardized test scores for US children have been dropping in recent years, and some administrators believe gym time can be better used to boost academic performance. Many experts however suggest that the physical activity doesn’t have to occur in a single bout of hour-long exercise. Shorter periods of activity that break up the hours-long school day may be just as effective as a single session, and may make it easier to work in physical education into school curricula.

One limitation of the analysis, however, is the fact that Singh deemed only two of the 14 studies as being high quality, meaning that the studies were set up in such as way that the both physical activity levels and academic performance were measured in a reliably objective way. Some of the studies depended on either the students or parents and teachers recalling how much exercise the children got over a certain period, and these surveys are always subject to bias.