Regular Exercise Keeps Brain Young

Nov. 14, 2005 -- Regular walks in the park may keep your mind young as well as your body in shape.

A new study shows that a lifetime of moderate exercise, such as walking 30 minutes or a light 1-mile run per day, can fight the effects of aging in the brain.

Researchers found rats that had access to exercise, in the form of a running wheel, throughout their lifetime had healthier DNA and less evidence of damaged brain cells than rats that were sedentary all their lives.

"For this study animals were not forced to run; they did it because it was entertaining, the same as a pet hamster on a running wheel," says researcher Thomas Foster, PhD, of the McKnight Brain Institute of the University of Florida, in a news release. "The results show that regular mild exercise can prevent oxidative damage. In people, that translates to a daily 30-minute walk or a light 1-mile run.

"It would be wonderful if we had a pill that contained all the benefits of exercise, but we don't," says Foster.

Exercising for Fun Keeps Brain Young

Researchers say oxidative damage in the brain is a natural consequence of aging and is thought to contribute to memory loss and other forms of age-related mental decline.

In the study, presented this week at the Society for Neuroscience's annual meeting in Washington, researchers compared the effects of moderate exercise on oxidative damage in the brains of rats that had lived to old age.

One group of rats had access to an exercise wheel throughout their lives, and the other group did not and led more sedentary lives.

After their death, researchers measured markers of oxidative damage in the animals' brains and found the more active rats had experienced less damage than the sedentary ones.

"The DNA for these animals after two years looked as if it were from their younger counterparts of only about 6 months of age," says Foster. "It shows a little bit of exercise may stimulate the body to fight stress that's normally occurring in the brain."

But experts say translating those results to humans may not be as simple.

"The difference between humans and rats is that it isn't as easy to get humans to exercise," Eric Klann, PhD, professor of molecular physiology and biophysics at the Baylor College of Medicine, says in the news release. "Put an exercise wheel in a rat cage and a rat will zoom around on that thing all the time, unless it's sleeping. But putting an exercise machine in your family room doesn't mean you're going to use it."