Jennifer Lovejoy, Arivale Chief Science Officer, PhD
[Arivale Hot Topics address health stories currently in the news. The Arivale Clinical Team’s commentary on these news articles is not a review of the scientific evidence, nor an endorsement of a specific study, and is not meant as official medical opinion.]
Exercise is good for our bodies. That’s no surprise. A broad range of benefits to our physical health may be achieved through at least 150 minutes of moderate intensity exercise or 75 minutes of vigorous exercise per week, according to the U.S. Department of Health and Human Services, American Heart Association, and American College of Sports Medicine.
But, what about our minds? It hadn’t been previously determined how much exercise is necessary to support cognitive health.
Age-related cognitive impairment and Alzheimer’s disease are on the rise, and interventions to reduce risk are very important, as reducing risk is a key component in prevention.
A systemic review published last month in Neurology: Clinical Practice and covered by Time included 98 studies associating cognition with exercise. Cognitive function was assessed via 122 various tests of brain function across all studies.
The review, which was led by an assistant professor of physical therapy and neurology at the University of Miami, included over 11,000 individuals with a mean age of 73. Participants included individuals with no cognitive deficits and those with mild cognitive impairment and dementia. Their level of exercise ranged from sedentary to regular, and the average duration among exercisers was 60 minutes three times per week.
Based on the data reviewed, it was found that people who exercised at least 52 hours over the course of six months showed the greatest improvement in their ability to process information and solve problems through a variety of thinking and speed tests. The beneficial effects were seen both in individuals with and without noted cognitive impairment or dementia.
The most frequently reported exercise mode was aerobic, followed by combined aerobic and resistance training, resistance training in isolation, and mind-body exercises.
The results of the systematic review are consistent with current exercise recommendations for overall health – about 150 minutes per week of exercise. This level of exercise may, in fact, be a key factor in improving brain health, even in those with current cognitive impairment.
There were, however, some limitations to the review.
First, it wasn’t able to stratify for session time, exercise frequency, intensity, and weekly minutes. It found only a strong correlation between brain function and overall time of exercise – not any of those other factors.
Nearly 60 percent of participants were sedentary, suggesting that combating sedentary behavior is a contributing factor to the results observed. It’s unclear whether similar cognitive effects can be seen in response to exercise in physically active individuals.
Only seven of the 98 studies assessed demonstrated maintenance of effects at follow-up. Future studies should assess short-term and long-term follow-up of effects of exercise on cognitive functioning.
Finally, the median age of the study participant was 73. It’s unclear whether younger individuals would see the same benefits. A prospective study of 10,000 adults with a mean follow-up time of 27 years found that midlife physical activity – 10 to 28 years before diagnosis – didn’t prevent a dementia diagnosis later in life, suggesting a lack of neuroprotective effects.
Overall, research suggests exercise is one of the most important things you can do to improve your brain health and delay cognitive aging. Aim to find an exercise routine that you enjoy and that you’ll be able to perform on most days of the week.