October 20, 2008
Aerobic Exercise May Slow, Reverse Age-Related Brain Decline
A new British study finds that consistent aerobic exercise can prevent age-related decline in brain function, and may even help reverse aging of the brain.
The study, conducted by two field experts from the University of Illinois Beckman Institute, was based on a review of previously published research.
Age-related deterioration in the brain's crucial white and gray matter makes a number of advanced "executive function" tasks more problematic, wrote Drs. Arthur F. Kramer and Kirk I. Erickson in a report about their work. Yet a significant body of research shows that these are the very processes that respond most to physical exercise, they said.
Moderate physical exercise, at a level that would make a person breathless, has been shown to increase both the speed and sharpness of thought in people with or without signs of Alzheimer's disease or dementia. Furthermore, exercise has also been shown to improve the volume of brain tissue and the way in which the brain functions, the experts said.
For example, Kramer and colleagues conducted a 6-month study with adults aged 60 to 75 who walked briskly for 45 minutes a day three days a week. They found that both the aerobic fitness and mental ability of the participants improved when compared with a control group who performed only in non-aerobic toning and stretching exercises. In particular, the group who performed aerobic exercise saw significant improvements in their ability to perform executive function tasks.
These results suggest that regular aerobic exercise can "reliably reverse age-related cognitive decline," wrote Kramer and Erickson, and that the aging brain maintains its capacity to grow and develop.
Previous research has found that adults who are more physically fit have less evidence of gray matter deterioration than their less-fit peers. Such gray matter is critical to a person's thinking abilities.
Other studies have shown that physically fit women going through menopause, which typically comes with declining estrogen levels and memory problems, have more gray brain matter and better executive control than their less physically fit counterparts, regardless of whether they took hormone replacement therapy, which can improve cognitive function.
Kramer and Erickson acknowledged that "many questions remain unanswered" about the effect of exercise on the brain. However, "we can safely argue that an active lifestyle with moderate amounts of aerobic activity will likely improve cognitive and brain function, and reverse the neural decay frequently observed in older adults," they wrote.
On The Net:
British Journal of Sports Medicine