For a recently published study in the journal Neurology, Clinton Wright of the University of Miami in Florida and colleagues looked at 876 seniors in northern Manhattan starting at an average age of 71 and measured their cognitive abilities at the beginning and end of a five-year period. Participants who had exercised regularly during that time were found to exhibit less of a mental decline than those who barely exercised at all. Overall, MRI scans showed that the brains of people who exercised moderately looked 10 years younger than those who didn't.
The physically active individuals also had a leg up on the other group when it came to vascular health. Researchers believe there's a connection between these two factors: regular exercise means lower blood pressure, which in turn can reduce the risk of stroke.
While these results are good news for older folk looking to keep their memories sharp, developing an exercise habit doesn't necessarily impact every brain equally. Individuals who displayed declining cognitive function at the beginning of the experiment weren't able to slow its progress with exercise, suggesting that physical activity only helps in this area before symptoms of memory loss have already started to show.
Recent research indicates that exercise can also have brain-boosting benefits at any age. When rats were subjected to a seven-week workout regimen, their hippocampus displayed significant neuron growth, but only if they were running and not lifting weights.
[h/t New Scientist]