A few minutes of exercise can help children with attention deficit hyperactivity disorder perform better academically, according to a new study led by a Michigan State University (MSU) researcher.

The study, published in the current issue of the Journal of Pediatrics shows for the first time that kids with ADHD can better drown out distractions and focus on a task after a single bout of exercise. Scientists say such 'inhibitory control' is the main challenge faced by people with the disorder.

While drugs have proven largely effective in treating many of the 2.5 million school-aged American children with ADHD, a growing number of parents and physicians worry about the side effects and costs of medication.

Matthew Pontifex, MSU assistant professor of kinesiology, who led the study, said: "This provides some very early evidence that exercise might be a tool in our nonpharmaceutical treatment of ADHD.

"Maybe our first course of action that we would recommend to developmental psychologists would be to increase children's physical activity."

In the study, Pontifex and colleagues asked 40 children aged eight to 10, half of whom had ADHD, to spend 20 minutes either walking briskly on a treadmill or reading while seated.

The children then took a brief reading comprehension and math exam similar to longer standardized tests. They also played a simple computer game in which they had to ignore visual stimuli to quickly determine in which direction a cartoon fish was swimming.

The results showed all of the children performed better on both tests after exercising. In the computer game, those with ADHD also were better able to slow down after making an error to avoid repeat mistakes - a particular challenge for those with the disorder.

Pontifex said the findings support calls for more physical activity during the school day. Other researchers have found that children with ADHD are less likely to be physically active or play organized sports.

Meanwhile, many schools have cut recess and physical education programs in response to shrinking budgets.

To order a copy of the full report, click here for Journal of Pediatrics.