The benefits of exercise for physical health are well known, but a new report suggests that staying active can help the elderly keep their minds in shape as well.
In a study of women aged 65 and older, those who were the most physically active at the start of the study were least likely to experience a decline in their mental abilities during the next 6 to 8 years.
"Exercise seems to be good for the brain/mind as well as for the body," the study's lead author, Dr Kristine Yaffe, of the University of California, told Reuters Health. "This does not have to be strenuous activity. Even moderate activity is beneficial."
After turning 65, at least 10% of people begin to experience a decline in their intellectual abilities. After age 85, this percentage jumps to at least 50%. Some research has suggested that physical activity may help prevent this mental decline, but the evidence is not conclusive.
The research study
To investigate the link between physical activity and mental health, Yaffe and her team enrolled nearly 6 000 elderly women, most of whom were white. The researchers tested the women's mental abilities at the start of the study and 6 to 8 years later. At the beginning of the study, they asked women how far they walked each day and calculated how many calories the women burned each week walking, climbing stairs and performing other types of physical activity.
The women who were most active at the start of the study were least likely to decline mentally during the study, Yaffe and her colleagues report in an issue of the journal Archives of Internal Medicine.
Twenty-four percent of the women who walked the least each week experienced a decline in their mental abilities, compared with 17% of the women who walked the most, about 17 miles a week. Yaffe and her colleagues estimate that for every mile a woman walked per day, her risk of mental decline dropped 13%.
The reduction in mental decline was similar when calculated using the number of calories the women burned each week.
Physical activity still significantly reduced the risk of mental decline even after the investigators took into account several factors that might have affected the results, including age, educational level, smoking, use of hormone replacement therapy and physical health.
Future study necessary
"We need to determine if these results are applicable to men and other groups, especially diverse ethnic groups," Yaffe said. It will also be important, according to the California researcher, to try to find out how physical activity keeps the brain fit.
The researchers are not certain how physical activity prevents intellectual decline, but they suggest that the apparent benefits may be related to a healthy lifestyle, a reduced risk of heart disease or direct benefit to brain cells.
It will also be important, according to Yaffe's team, to see whether a program to increase physical activity in the elderly can prevent declines in mental abilities. - (HealthScout)