Regular Aerobic Exercise May Help Your Brain Age Better

Getting in your daily workout may not only keep your body healthy but your brain thriving too. New research finds that one year of regular moderate-to-vigorous aerobic exercise may be able to improve your memory and mental skills.

The small study examined 37 people between ages 55 and 80 years who had mild cognitive impairment. They found that aerobic exercise improved:

• Cardiorespiratory fitness
• Cerebral blood flow regulation
• Memory and executive function

These findings suggest that aerobic exercise training that improves blood flow in the brain may help treat or slow forms of dementia, including Alzheimer’s disease.

Dysfunction of the regulatory system of blood flow in the brain is one of the possible mechanisms behind the condition, according to Tsubasa Tomoto, PhD, lead study author and postdoctoral fellow in the Department of Neurology at the University of Texas Southwestern Medical Center.

The July study was published in the Journal of Applied Physiology.

How Aerobic Exercise Helps

For the study, Tomoto and his colleagues assigned half of the participants to a program of aerobic exercise training that was designed to increase cardiorespiratory fitness. The other half engaged in stretching and toning exercises.

All participants in the study had previously been sedentary. Half were assigned to a program of brisk walking three times a week, starting with one month of training and then continuing on their own.

They could walk outside or indoors on a treadmill and were taught to monitor their heart rate and keep it between 85% and 90% of their maximum heart rate.

The rest of the participants were taught stretching and toning exercises, which they did three times a week. This group was asked to keep their heart rates below 50% of their maximum heart rate.  

The researchers were testing to see if changes in cerebral vasomotor reactivity are associated with cognitive performance. Vasomotor reactivity is how the velocity of blood flow changes in response to changes in CO2 levels.

They measured CO2 levels at their lowest and highest in the participants. Researchers also ran tests for memory and executive function, which are the mental skills needed to plan, focus attention, remember instructions, and perform multiple tasks.

The team found that there were mild improvements in cognitive performance in those participants who exercised aerobically for a year. The exercise appeared to decrease high CO2 cerebral vasomotor reactivity. This decrease was associated with improved scores in cognitive performance tests.

Improving cardiorespiratory fitness shows a lot of promise in improving cognitive function in people with mild impairment, Tomoto tells Verywell. The cause of Alzheimer’s disease is still not completely understood, he notes, but blood circulation in the brain may be a factor.

“The important thing is the exercise, trying to improve the cerebral blood flow regulation,” he says.

More Research Is Needed

The study itself is limited. It was conducted on a small set of participants and, since forms of dementia including Alzheimer’s usually have a gradual onset, the one-year term of the study may be too short to show the real significance of these results, Tomoto says.

He and his colleagues have begun a similar study that will run over a longer period of time.

Studying whether moderate-to-vigorous aerobic exercise earlier in life can prevent loss of cognitive function or slow down its onset would also be important, he says. “Prevention of Alzheimer’s is a key right now. The most important thing is prevention” Tomoto adds.

"While this is a small study, the findings are in line with what has been shown in similar studies examining aerobic exercise and the brain," Claire Sexton, DPhil, director of scientific programs and outreach with the Alzheimer’s Association, tells Verywell via email. “In particular, this study shines a advisory-grouplight on the impact of aerobic exercise on cerebrovascular function but is too small to provide new insights regarding cognition," Sexton says.

Regular aerobic exercise is a valuable part of a healthy lifestyle and has already been shown to be associated with a reduced risk of cognitive decline, Sexton adds. “Getting the blood pumping through regular physical exercise is good for cardiovascular health, and we know what's good for the heart is good for the brain,” she says.

A two-year clinical study of changes in lifestyle, called U.S. POINTER, is also underway, she notes. It is evaluating whether lifestyle interventions that simultaneously target multiple risk factors protect cognitive function in older adults who are at increased risk for cognitive decline.

“It's never too early or too late to start adopting healthy habits that may decrease your risk for cognitive decline," she says.