A Link Between Good Grades and Exercise?The more physical activity a child engages in, the better their performance at school. At least, that’s the suggestion from a new review of previously published research looking at the relationship between academic performance and exercise in children.

All of the 14 studies the researchers identified for review were conducted in the U.S. or Canada, except for one done in South Africa.

Sample sizes ranged from 53 to about 12,000 participants between the ages of 6 years and 18 years. Follow-up varied from eight weeks to more than five years.

The research was conducted by Amika Singh, Ph.D., of the Vrije Universiteit University Medical Center, Amsterdam, the Netherlands, and his colleagues. They were interested in reviewing the data between physical activity and academic performance because of concerns that pressure to improve test scores may often mean more instructional time for classroom subjects with less time for physical activity.

“According to the best-evidence synthesis, we found strong evidence of a significant positive relationship between physical activity and academic performance,” wrote the researchers.

“The findings of one high-quality intervention study and one high-quality observational study suggest that being more physically active is positively related to improved academic performance in children.”

Exercise may help children’s thinking by increasing blood and oxygen flow to the brain. It may also help by increasing levels of norepinephrine and endorphins to decrease stress and improve mood, and increasing growth factors that help create new nerve cells and support synaptic plasticity.

Still, “relatively few studies of high methodological quality have explored the relationship between physical activity and academic performance,” the authors conclude. No study in their systematic review used an objective measure of physical activity.

“More high-quality studies are needed on the dose-response relationship between physical activity and academic performance and on the explanatory mechanisms, using reliable and valid measurement instruments to assess this relationship accurately,” the authors conclude.

The new research appears in the January2012 issue of the journal Archives of Pediatrics & Adolescent Medicine.

Source: JAMA