Remaining physically active as you age, a new study shows, may help protect parts of your brain from shrinking, a process that has been linked to declines in thinking and memory skills. Physical exercise not only protected against such age-related brain changes, but also had more of an effect than mentally and socially stimulating activities.
In the new report, published in the journal Neurology, a team at the University of Edinburgh followed more than 600 people, starting at age 70. The subjects provided details on their daily physical, mental and social activities.
Three years later, using imaging scans, the scientists found that the subjects who engaged in the most physical exercise, including walking several times a week, had less shrinkage and damage in the brain’s white matter, which is considered the “wiring” of the brain’s communication system. The relationship remained even after the researchers controlled for things like age, health status, social class and I.Q.
As far as mental exercise, “we can only say we found no benefit in our sample,” said Dr. Alan J. Gow, an author of the study and a senior research fellow at Edinburgh. He added: “There might be associations earlier in the life course. Such activities also have important associations with well-being and quality of life, so we would certainly agree it is important for older adults to continue to pursue them.”
Because the findings showed only an association, not a causal relationship, the authors could not rule out the possibility that people with less deterioration in their brains were simply more likely to be physically active. But they said that based on their findings, they would advise that people take up physical exercise “whatever their age.”
A version of this article appeared in print on 10/30/2012, on page D6 of the NewYork edition with the headline: Regimens: Exercise May Protect Brain’s Size.