March 25, 2026
Older adults who regularly engaged in exercise sessions lasting at least 10 minutes at a leisurely pace had healthier brains than their sedentary peers, according to a new report. The findings add to growing evidence that even short periods of low-intensity exercise can help to keep the brain in good working order as we age.
For the study, researchers at the University of California, San Francisco, looked at 279 older men and women who were part of the Brain Aging Network for Cognitive Health (BrANCH) study, an ongoing investigation of aging and brain health. Their mean age was 72. All were free of serious memory problems, including Alzheimer’s disease or other forms of dementia, and lived at home in the San Francisco area.
Study participants wore FitBit activity monitors on their wrists continuously for 30 days, so that the researchers could record their typical, minute-to-minute physical activity patterns. The volunteers also underwent regular tests of memory and thinking skills, as well as MRI brain scans to assess the health of their brains.
About four out of five of the group got some kind of regular exercise, which the researchers defined as at least 10 minutes moving at a step cadence of at least 40 steps per minute. This level of exercise is generally considered low-intensity exercise, such as taking a leisurely walk, compared to moderate or vigorous exercise, such as jogging or running. Average exercise sessions lasted about 25 minutes, and participants averaged about four such sessions a week.
The researchers found that older adults who got at least 10 minutes of regular exercise had healthier brains than their sedentary peers. MRI scans revealed fewer abnormal areas, or lesions, in the brain’s white matter, which are regions that support and connect neurons. These lesions, known as white matter hyperintensities, are linked to cognitive decline and a higher risk of Alzheimer’s disease.
Those who got regular exercise also scored better on tests of executive function, or the ability to carry out high-level brain skills such as planning, organizing and making decisions. Executive function is typically impaired early in the course of Alzheimer’s disease.
Both the exercisers and those who didn’t engage in regular exercise sessions took, on average, about 6,000 steps a day. But exercising for at least 10 minutes at a time, even at low intensity, seemed to be key for better brain health. More frequent and more vigorous exercise was tied to better brain health markers, though none of the adults in the study were high-intensity athletes.
The study did not distinguish between aerobic activities like walking and non-aerobic resistance training like lifting weights, but both forms of exercise have been shown to be important for healthy aging in separate studies. The authors note that regular physical activity has been shown to promote blood vessel health and improve circulation throughout the body, including in the brain. Regular exercise can also lower levels of body-wide inflammation and reduce the risk of metabolic disorders like diabetes, which may reduce your risk of developing Alzheimer’s disease.
“Any physical activity may be better than no activity, but engagement in some physical activity sessions of at least 10 minutes and at least low intensity is associated with lower white matter injury in older adults without dementia,” the authors concluded. “Regardless of increasing age, engaging in shorter sessions of at least 10 minutes but at higher frequency and intensity may be optimal.” The findings were published in the journal Alzheimer’s Research and Therapy.
By ALZinfo.org, The Alzheimer’s Information Site. Reviewed by Eric Schmidt, Ph.D., Fisher Center for Alzheimer’s Research Foundation at The Rockefeller University.
Source: Cadwallader, C.J.; Pinheiro-Chagas, P.; Saloner, R; et al: “The active ingredients: physical activity features linked to healthy brain aging.” Alzheimer’s Research and Therapy, March 5, 2026
