“Some people work up quite a sweat when they are doing household chores,” said Dr. Sandra Weintraub, a neurologist at Northwestern University’s Feinberg School of Medicine, who was not associated with this study. “It might be that if you do three hours of household chores, you are as good as if you did 30 minutes of aerobic exercise.”
For Dr. Salinas, who recommends that people aim for 150 minutes of moderate- to high-intensity exercise a week, the results strengthen the idea that regular moderate to vigorous exercise can promote brain health. Cultivating this habit of exercise “is likely to have a very profound synergistic effect,” he said. “You get a lot more bang for your buck in terms of helping to promote your own health through physical activity.”
Perhaps most encouragingly, the association between physical activity and a reduced risk of dementia extended to participants who had a family history of dementia.
“It’s very important to know that if you have a family history of dementia, you can use physical activity to reduce your risk,” Dr. Song said.
Start by doing what you like best.
The second paper, published last week in Neurology, compiled 38 studies to see which leisure activities were associated with a reduced risk of dementia. Altogether, the studies followed more than two million participants without dementia over at least three years, during which time 74,700 developed dementia.
After controlling for age, education and gender, the researchers found that participants who exercised regularly — defined as engaging in activities such as walking, running, swimming, dancing, participating in sports or working out at the gym — had a 17 percent lower risk of developing dementia compared with those who did not.
This meta-analysis shows that dementia prevention is not limited to one activity, or even one type of activity. Given the diversity of physical activities that participants engaged in, “we recommend to people to do the exercise that you like,” said Le Shi, a researcher at Peking University and one of the study’s authors.