Exercise (2015) & Brain Volume & Aging

Learn more about Alzheimer's disease and cognitive impairment. Also see more information on exercise and the brain.

Researchers have been developing an understanding that exercise improves mental functioning, known as cognitive functioning. But what is less understood is the relationship between cognitive capacity and the size of the brain. In many cognitive disabling conditions it has been observed that the physical size of the brain shrinks.

Researchers devised research to examine this relationship. They selected 110 people who were over 65 and who were healthy. Most of them were enrolled into an exercise group and they used home-based exercise regimens as well.

The study lasted for 2 years, and for an additional 6 months the researchers monitored the subjects after they had stopped the exercise programs.

The researchers used techniques such as MRI to produce images of the participants' brains during the course of the study. They found that while brain volume normally decreases with age, in these subjects prefrontal (both sides) volume was preserved but the benefit faded after the participants ceased the exercise program. The prefrontal part of the brain, the front of the brain, is needed for planning, cognitive behavior, decision making, and how the personality expresses itself. This is the part of the brain whose failure is most immediately noticeable in patients with cognitive impairment.

The scientists also monitored the participants' cognitive functioning in areas such as attentional shift. Attentional shift simply means the ability to shift the vision and thus attention from one point to another and to maintain that attention. Normally as we age it is increasingly difficult to maintain attention to one point. These patients saw improvement in this regard. This improvement persisted during the 6 months following the 2 year exercise period.

Researchers: M. Tamura, K. Nemoto, et al
Published: Long-term mild-intensity exercise regimen preserves prefrontal cortical volume against aging, International Journal of Geriatric Psychiatry, July, 2015.