After compiling all of the studies, the researchers found that exercise did seem to reduce the risk of dementia later in life. For example, in one study (which looked only at men and women over 65) those who exercised from 15 to 30 minutes three times a week were significantly less likely to develop Alzheimer’s disease that those who didn’t exercise at all. Moreover, it seems that the cognitive benefits of exercise don’t wear off quickly, but instead last for several decades.
And staying active by doing aerobic activities, like walking or running, seems to help more than simple stretching or building muscle. One study found that older adults who walked on a set schedule for six months were more focused during tasks than those who did stretching and toning exercises.
But how does exercise keep one’s brain young?
To answer this question, researchers looked at brain function and physical activity in 62 to70 year olds. “Those who continued to work and retirees who exercised showed sustained levels of cerebral blood flow and superior performance on measures of cognition as compared to the group of inactive retirees,” said Kramer.
More research needs to be done to determine which exercises are best for keeping the brain fit, the authors write, but it does seem that the increased blood supply to the brain as a result of aerobic exercise plays an important role in keeping senior’s minds sharp.
