Doing this activity just twice a week is a ‘strong ally against dementia’ — even if you’re high-risk

Pumping it up may pump the brakes on cognitive decline.

Alzheimer’s cases are expected to nearly double by 2050, reaching a staggering 13 million cases. And while genetics certainly come into play, there are some lifestyle factors that can raise — or lower — your risk.

Now, researchers in Brazil have pinpointed a change that seniors can make just two times a week to protect themselves against dementia.

The researchers from the State University of Campinas (UNICAMP) in São Paulo studied 44 elderly participants with mild cognitive decline, a condition that indicates a higher risk of dementia.

Published in the journal GeroScience, the team discovered that strength training not only improved cognitive function but changed the anatomy of the brain itself.

Participants were divided into two groups; the first engaged in twice-weekly, moderate to high-intensity weight training sessions, and the second group did not exercise at all during the study period.

After six months, the weight-training participants showed improved memory recall and neuron quality, or white matter integrity.

Further, areas of the brain related to Alzheimer’s disease — the hippocampus and precuneus — were protected from atrophy.

Meanwhile, the sedentary participants showed a worsening of brain parameters.

“We already knew that there would be a physical improvement. Cognitive improvement was also imagined, but we wanted to see the effect of weight training on the brains of older people with mild cognitive impairment,” said Isadora Ribeiro, a FAPESP doctoral fellowship recipient at UNICAMP’s School of Medical Sciences (FCM) and first author of the article.

“The study showed that, fortunately, weight training is a strong ally against dementia, even for people who are already at high risk of developing it.”

The benefits of weight training are well established: It supports and builds muscle mass, eases symptoms of menopause, and lowers the risk for a wide range of medical disorders, including cardiovascular disease and diabetes, by improving the brain’s ability to access and process glucose.

Experts agree that adults should aim for 150 minutes of moderate-intensity physical activity and two days of muscle strengthening a week for general health. 

A 2024 study found that people who participated in moderate to vigorous activity — exercise that increases their pulse rate and respiration for a minimum of 10 minutes — had more brain mass in multiple regions, such as the hippocampus, which is responsible for memory; gray matter, which helps process information; and the occipital, frontal and parietal lobes.

“A characteristic of people with mild cognitive impairment is that they have volume loss in some brain regions associated with the development of Alzheimer’s,” said Ribeiro.

“However, in the group that did strength training, the right side of the hippocampus and precuneus were protected from atrophy. This result justifies the importance of regular weight training, especially for older people.”

According to the team, weight training provides a two-pronged approach to fighting dementia.

It stimulates the production of neural growth factor — which promotes and supports healthy neurons) — and reduces inflammation in the body.

“Any physical exercise, whether weight training or aerobic activity, is known to increase levels of a chemical involved in brain cell growth. It can also mobilize anti-inflammatory T-cells. This is key,” said sturdy supervisor Marcio Balthazar.

“After all, the more pro-inflammatory protein that is released in the body, the greater the chance of developing dementia, accelerating the neurodegenerative process and forming dysfunctional proteins that eventually kill neurons.”

Even more promising is the team’s hypothesis that more extended periods of strength training could result in even more significant gains, both physical and mental.

Ribeiro notes that while all bodybuilding participants showed improvement in memory function and brain anatomy, five participants reversed their diagnosis of mild cognitive impairment.

“This leads us to imagine that longer training sessions, lasting three years, for example, could reverse this diagnosis or delay any kind of dementia progression. It’s certainly something to be hopeful about and something that needs to be studied in the future,” said Ribeiro.

Researchers are hopeful these findings will encourage patients and providers to explore these effective, accessible, and non-pharmacological measures for preventing dementia and improving mild cognitive impairment.