Exercise May Protect Brain Volume by Keeping BMI, Insulin Levels Low, Study Results Show

Exercise can play a role in maintaining body mass index (BMI) and insulin levels and protect brain volume, which may help prevent dementia, according to the results of a new study published in Neurology, the medical journal of the American Academy of Neurology.

“These results may help us to understand how physical activity affects brain health, which may guide us in developing strategies to prevent or delay age-related decline in memory and thinking skills,” Géraldine Poisnel, PhD, of Inserm Research Center in Caen, France, said in a statement. “Older adults who are physically active gain cardiovascular benefits, which may result in greater structural brain integrity.”.

Previous studies have also shown that exercise helps protect brain cells.

Investigators also found that the relation between exercise and the metabolism of glucose in the brain were not affected by BMI or insulin levels. The reduced glucose metabolism in the brain was only seen in individuals with dementia.

Investigators included 134 individuals, averaging aged 69 years, who did not have memory issues. The individuals filled out surveys about their physical activity for the previous year. They also received brain scans that measured glucose metabolism and volume.

Additionally, investigators gathered information about blood pressure, BMI, cholesterol, insulin levels, and other factors.

Investigators found that individuals with the most physical activity had higher total volumes of grey matter in their brains than individuals with the least amount of physical activity, which averaged to about 550,000 mm3 compared with about 540,000 mm3.

Furthermore, when investigators examined areas of the brain affected by Alzheimer disease (AD), they found similar results.

Additionally, those with the most activity also had higher average rates of glucose metabolism in the brain than those with the least amount of activity.

Higher physical activity did not show an association with how much amyloid plaque, a maker of Alzheimer disease (AD), individuals had in their brains.

Investigators said more research is needed to understand the mechanisms behind these relations.

“Maintaining a lower BMI through physical activity could help prevent disturbed insulin metabolism that is often seen in aging, thus promoting brain health,” Poisnel said.

The study did not prove that exercise protects brain volume, but an association was seen by investigators.

A limitation of the study was that individuals reported their own physical activity, so the activity could have been recorded incorrectly or incorrectly remembered, investigators said.

The study was supported by the European Union's Horizon 2020 Research and Innovation Program, Region Normandy, and MMA Foundation of Entrepreneurs of the Future.

Reference

Exercise may protect brain volume by keeping insulin and BMI levels low. ScienceDaily. News release. April 13, 2022. Accessed April 20, 2022. https://www.sciencedaily.com/releases/2022/04/220413161810.htm