Exercise is more effective at preventing age-related cognitive decline than doing crossword puzzles or other mentally or socially stimulating activities, says a new study from the University of Edinburgh. Researchers performed brain scans on more than 600 people in their early seventies and found that those who exercised didn't suffer nearly as much age-related brain shrinkage and other mental decay as those who did little or no physical activity. On the other hand, engaging in reputedly brain-boosting activities like completing a puzzle, learning a language, meeting friends, or doing other mental and social activities did nothing to prevent brain shrinkage, which is associated with dementia, memory loss, poor thinking, and increased risk of Alzheimer's disease.
Researchers also found that exercisers had more gray matter – the area of the brain primarily responsible for muscle control, memory, and emotions. "Exercise seems to have widespread effects on our brains," says Kirk Erickson, a psychology professor at the University of Pittsburgh, who was not involved in the study. "And it doesn't seem like we need much to reap the benefits – moderate-intensity exercise several days a week is sufficient for improving and maintaining brain health."