Research has shown that aerobic exercise, the kind that enhances cardiovascular fitness, can help older people stay sharp and improve problem-solving skills and other mental abilities.
A few years ago scientists at the University of Illinois at Urbana-Champaign showed, for the first time, that people over 60 who started an aerobic exercise program actually increased their brain volume, as seen on MRI scans. Lower brain volume is linked to increased cognitive impairment and dementia.
The best evidence yet of physical brain gains from aerobic exercise came this year from a study funded by the National Institute on Aging, published in the Proceedings of the National Academy of Sciences. In it, 120 sedentary older people without dementia either walked briskly for 40 minutes three days a week, or else did stretching and toning exercises.
After a year, MRIs revealed that the aerobic group had increased volume of the hippocampus, the part of the brain involved in memory formation, while the stretching group had normal age-related decreases in brain volume. In a spatial memory test, only the aerobic group showed improvements.
It used to be thought that brain shrinkage is almost inevitable in later life, and that the aging brain does not grow new cells. But this research has shown that even moderate exercise can not only keep the brain from shrinking, but even increase its size. It suggests that exercisers can develop new brain cells and, presumably, connections between them. Such changes would result in a brain that is more efficient and adaptive and less impaired by age-related changes.
Don’t forget strength training
Strength training helps build muscle mass, of course, but it can also benefit your brain, even when done just once a week, according to researchers from the University of British Columbia in Vancouver.
One of their studies, published in the Archives of Internal Medicine in 2010, involved 155 women age 65 to 75. They did strength training—40 minutes once or twice a week, for upper and lower body—for a year.
This resulted in improvements in tests of certain “executive cognitive functions,” which tend to decline with age. A follow-up study, in the same journal, found that some of the cognitive benefits were sustained a year after the formal exercise program ended, at least among the women who remained physically active.
This confirms earlier research, including a 2007 Brazilian study of men age 65 to 75, which found that six months of strength training provided cognitive benefits as seen in a variety of neuropsychological tests. Those investigators noted that, like aerobic exercise, strength training may improve blood flow to the brain, as well as other factors linked to cognitive improvements.