In people at high risk of Alzheimer’s disease, a half hour of aerobic exercise 4 to 5 times a week may delay brain deterioration, according to a proof-of-concept study published online in the Journal of Alzheimer’s Disease.
The study involved 70 sedentary adults age 55 or older with amnestic mild cognitive impairment. Participants were randomized to 12 months of regular aerobic exercise or a stretching-and-toning intervention.
Over the year-long trial, both groups maintained similar memory and executive function—and experienced the spread of amyloid plaques. However, participants in the aerobic exercise group who had amyloid buildup experienced slightly less volume reduction in the hippocampus, compared with peers in the stretching and toning group, according to the study.
“It’s interesting that the brains of participants with amyloid responded more to the aerobic exercise than the others,” said researcher Rong Zhang, PhD, a professor at UT Southwestern Medical Center, Dallas, Texas. “Although the interventions didn’t stop the hippocampus from getting smaller, even slowing down the rate of atrophy through exercise could be an exciting revelation.”
While noting the trial was a proof-of-concept investigation and that definitive conclusions can’t be drawn at this point, further research is warranted, Dr. Zhang said.
“What are you supposed to do if you have amyloid clumping together in the brain? Right now, doctors can’t prescribe anything,” he said. “If these findings can be replicated in a larger trial, then maybe one day doctors will be telling high-risk patients to start an exercise plan. In fact, there’s no harm in doing so now.”
Tarumi T, Rossetti H, Thomas BP, et al. Exercise training in amnestic mild cognitive impairment: a one-year randomized controlled trial. Journal of Alzheimer’s Disease. 2019 August 8;[Epub ahead of print].