Physical activity good for the body and mind

By Megan Rauscher

NEW YORK (Reuters Health) - In a cross-sectional study on health and aging, older women who were more active during the day did better on tests of their cognitive function.

"This was especially true for tests that involved something called executive function, which is basically your ability to plan and execute daily tasks," Dr. Deborah E. Barnes, who led the study, told Reuters Health. "No matter how old you are, it is important to stay active."

The study involved 2,736 elderly women without evidence of dementia. After removing the influence of age, race, and education, Barnes of the University of California at San Francisco and colleagues found that women who were the most active, compared with those who were the least active, posted better average scores on several standard cognitive tests and were less likely to be cognitively impaired.

"All of these women were quite elderly; the average age was 83," Barnes noted, "so this seems to suggest that being active continues to be important even in very late life."

She also noted that most prior studies that have looked at the relationship between cognitive function and activity levels have relied on self-reports, or asking people questions about their activity levels. "We used an objective measure called actigraphy. An actigraph is something you wear on your wrist, and it measures all of your wrist movements. This includes things like swinging your arms while walking, playing bridge with friends and doing chores around the house. So it provides an objective measure of total daily activity," Barnes explained.

The study findings appear in a report in the Journal of the American Geriatrics Society.

According to Barnes, one limitation of this study is that all of the information was collected at a single point in time. "Therefore, based on this study alone, we don't really know whether more activity leads to better cognitive function, or whether better cognitive function leads to more activity," she said.

"But when you look at all of the studies together, you start to see a pretty compelling picture suggesting that being active is good for your brain as well as your body," she added.

SOURCE: Journal of the American Geriatrics Society, September 2008.