Exercise is as good for the mind as it is for the body—considering the overwhelming evidence that keeping active keeps blood flowing to the brain and lowers the risk of dementia later in life, getting your 10,000 steps in is a no-brainer. But is 10,000 enough to have an impact on your dementia risk? And exactly how vigorous should the exercise be to reap the blood-pumping benefits?
A new study suggests that the threshold to make a difference in dementia risk is 52 hours per six-month period. When compared to a group that exercised 34 hours over a six-month period, researchers found that the group who exercised for 52 hours showed improvement in thinking skills, while the group that exercised less did not. To find that number, scientists at University of Miami Miller School of Medicine looked at over 100 studies involving 11,061 people with an average age of 73. On average, those in the group that improved exercised for about an hour, three times per week. And these improvements were seen in those with mild cognitive impairment and those with normal cognitive function.
The most significant finding from the study was that it didn’t seem to matter how often a person exercised, or how intensely—what mattered most was the overall time a person spent exercising. Scientists say that this supports the idea that brain health is affected by the accumulation of your exercise habits.
All of the studies the researchers used to compile the results were randomized controlled trials, the gold standard for clinical trials used to figure out a cause-and-effect relationship.
“These results suggest that a longer-term exercise program may be necessary to gain the benefits in thinking skills,” said study author Joyce Gomes-Osman, Ph.D., of the University of Miami Miller School of Medicine. “We were excited to see that even people who participated in lower intensity exercise programs showed a benefit to their thinking skills. Not everyone has the endurance or motivation to start a moderately intense exercise program, but everyone can benefit even from a less intense plan.”
And as for the type of exercise, that didn’t make a difference, either. Participants engaged in everything from aerobic exercise to tai chi, and researchers did not find an association between improved memory and a certain type of exercise. The overall message? Get moving regularly.
“Only the total length of time exercising could be linked to improved thinking skills,” said Gomes-Osman. “But our results may also provide further insight. With a majority of participants being sedentary when they first enrolled in a study, our research suggests that using exercise to combat sedentary behavior may be a reason why thinking skills improved.”
This study was published in the journal Neurology.