High school students run at sunset as they practice track and field season on February 28, in Shawnee, Cannes. New research suggests that even simple exercise may help avoid memory problems. While physical activity helps maintain healthy minds, it’s not clear how much it helps once the memory starts to slip. (Charlie Riddle, The Associated Press)
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WASHINGTON — New research suggests that even simple exercise may help older Americans with mild memory problems.
Doctors have long recommended physical activity to help keep the brain healthy. But the government-funded study represents the longest-running test of whether exercise makes any difference once memory starts to slip — research being conducted amid a pandemic that has added isolation to the list of risks to participants’ brain health.
The researchers recruited about 300 sedentary older adults with hard-to-identify memory changes called mild cognitive impairment, or MCI — a condition that is sometimes, but not always, a precursor to Alzheimer’s disease. Half were assigned to aerobic exercises and the rest to stretching and balancing movements that only raised the heart rate modestly.
Another key component: Participants in both groups were inundated with the attention of coaches who worked with them at YMCAs across the country — and when COVID-19 closed gyms, he helped them keep moving around the house via video calls.
After a year, cognitive testing showed neither group had worsened, said lead researcher Laura Becker, a neuroscientist at the Wake Forest School of Medicine. She said brain scans did not show the shrinkage associated with worsening memory problems.
By comparison, similar MCI patients in another long-term study of brain health—but without exercise—experienced significant cognitive decline over a year.
These early results were surprising, and the National Institute on Aging cautioned that tracking non-exercisers in the same study would have provided better evidence.
But the findings suggest that “it’s possible for everyone” — not just older adults who are healthy enough to work up a sweat, said Baker, who presented the data Tuesday at the Alzheimer’s Association International Conference. “Exercise should be part of prevention strategies” for older people at risk.
Previous research has found that regular physical activity of any kind may reduce harmful inflammation and increase blood flow to the brain, said Maria Carrillo, scientific director of the Alzheimer’s Association.
But the new study is particularly interesting because the epidemic has spread midway through, leaving already vulnerable older adults socially isolated — something that has long been known to increase people’s risk of memory problems, Carrillo said.
It’s a frustrating time for dementia research. Doctors are reluctant to prescribe an expensive new drug called Aduhelm that was supposed to be the first to slow the progression of Alzheimer’s disease — but it’s not yet clear if it really helps patients. Researchers reported last month that another drug that works similarly — by targeting amyloid plaques that are a hallmark of Alzheimer’s disease — failed in a major study.
While amyloid plays an obvious role, it’s important that drugmakers increasingly target the many other factors that can lead to dementia, Carrillo said, because effective treatment or prevention likely requires a range of customized strategies.
One example of a new approach: Sometimes in dementia, the brain has trouble processing blood sugar and fats to get the energy it needs, John Didsbury of T3D Therapeutics told the Alzheimer’s Meeting. His company is testing a pill that aims to increase the metabolic rate, with results expected next year.
Meanwhile, there is an urgent need to iron out whether steps people can take today – such as exercise – may offer at least some protection.
How much and what type of exercise? In Becker’s study, older adults were required to move for 30 to 45 minutes four times a week, whether it was vigorous spins on the treadmill or stretching exercises. That’s a big request for anyone who’s sedentary, but Baker said MCI’s effects on the brain make it difficult for people to plan and stick to the new activity.
Hence the social stimulation — which she said resulted in each participant completing more than 100 hours of exercise per year. Becker suspects that the sheer size may explain why even simple stretching adds to a clear benefit.
“We wouldn’t have done this exercise alone,” said retired agricultural researcher Doug Maxwell of Verona, Wisconsin, who joined the study with his wife.
The duo, both 81, are set to take stretching classes. They felt so good afterward that when the study ended, they bought electric bikes hoping for more activity—Maxwell admitted it was hard to keep up.
Next up: Becker is leading a larger study of older adults to see if adding exercise to other harmless steps like a heart-healthy diet, brain games and social stimulation together might reduce the risk of dementia.