New research suggests even a simple exercise routine could help older Americans with mild memory problems.
Doctors have long recommended physical activity to keep a healthy brain fit. But the government-funded study represents the longest-running test of whether exercise makes a difference once memory begins to decline — research conducted amid a pandemic that added isolation to the list of risks to participants’ brain health.
Researchers recruited about 300 sedentary older adults with hard-to-detect memory changes called mild cognitive impairment, or MCI — a condition that is sometimes, but not always, a precursor to Alzheimer’s. Half were assigned aerobic exercise and the rest were assigned stretching and balance exercises, which only slightly increased their heart rate.
Another key component: Participants in both groups were showered with attention from trainers who had worked with them at YMCAs across the country — and when COVID-19 closed gyms, video calls helped them move on at home.
After a year, cognitive testing showed that no group had deteriorated overall, said lead researcher Laura Baker, a neuroscientist at Wake Forest School of Medicine. Nor did brain scans show the shrinkage that accompanies worsening memory problems, she said.
In comparison, in another long-term brain health study, similar MCI patients experienced significant cognitive decline — but without exercise — over a year.
These early findings are surprising, and the National Institute on Aging warned that tracking non-exercisers in the same study would have provided better evidence.
But the results suggest that “this is doable for anyone” — not just seniors who are healthy enough to sweat profusely, said Baker, who presented the data Tuesday at the Alzheimer’s Association International Conference. “Exercise must be part of prevention strategies” for vulnerable seniors.
Previous research has found that regular physical activity of any kind can reduce harmful inflammation and increase blood flow to the brain, said Maria Carrillo, chief scientific officer of the Alzheimer’s Association.
But the new study is particularly intriguing because the pandemic hit midway, leaving already vulnerable seniors socially isolated — something that has long been known to increase the risk of memory problems, Carrillo said.
It’s a frustrating time for dementia research. Doctors are reluctant to prescribe a high-priced new drug called Aduhelm, which initially aims to slow the progression of Alzheimer’s – but it’s not yet clear if it’s actually helping patients. Researchers reported last month that another drug that works similarly – by targeting amyloid plaques, which is a hallmark of Alzheimer’s – failed in a pivotal study.
While amyloid clearly plays a role, it’s important that drugmakers increasingly target many other factors that can lead to dementia, Carrillo said, since effective treatment or prevention likely requires a combination of tailored strategies.
An example of a new approach: Sometimes in dementia, the brain has trouble processing blood sugar and fats for the energy it needs, T3D Therapeutics’ John Didsbury said at the Alzheimer’s meeting. His company is testing a pill aimed at boosting that metabolism, with results expected next year.
In the meantime, there’s growing urgency to clarify whether actions people might be taking today — like exercise — could offer at least some protection.
How much and what kind of exercise? In Baker’s study, seniors were asked to exercise for 30 to 45 minutes four times a week, whether it was a vigorous treadmill spin or stretching. That’s a big question for anyone who’s sedentary, but Baker said MCI’s effects on the brain make it even harder for people to plan and maintain the new activity.
Hence the social stimulation — which she attributed to every participant who completed over 100 hours of exercise. Baker suspects the sheer volume might explain why even simple stretching resulted in an obvious benefit. Participants were scheduled to continue training for another six months without formal support, data Baker has yet to analyze.
“We wouldn’t have done the exercise on our own,” said retired agricultural researcher Doug Maxwell of Verona, Wisconsin, who participated in the study with his wife.
The duo, both 81 years old, were both assigned to stretching classes. They felt so good afterwards that they bought electric bikes after completing the study in hopes of even more activity — efforts Maxwell acknowledged are difficult to sustain.
Next up: Baker is leading an even larger study in older adults to see if adding exercise to other steps that can’t hurt, like a heart-healthy diet, mind games and social stimulation, can reduce the risk of dementia.
The Associated Press Health and Science Department receives support from the Howard Hughes Medical Institute’s Department of Science Education. The AP is solely responsible for all content.