Exercise & Brain Health: Lower Alzheimer’s Risk & Boost Memory
Researchers have identified a specific subtype of brain cells, astrocytes, that appear to be strengthened by exercise and may protect against the cellular damage associated with Alzheimer’s disease, according to a study published in Nature Neuroscience on June 12, 2025. The findings, based on research using a mouse model, offer modern insights into the mechanisms by which physical activity benefits brain health and could inform future treatment strategies.
The research team, led by Dr. Christiane Wrann at Massachusetts General Hospital, utilized a technique called single-nucleus RNA sequencing (snRNA-seq) to analyze gene activity at the single-cell level in the hippocampus – a brain region critical for memory and learning – of both exercised and sedentary mice with Alzheimer’s-like symptoms. The study focused on the dentate gyrus, an area within the hippocampus particularly vulnerable to changes during both exercise and the progression of Alzheimer’s disease.
Mice allowed free access to a running wheel for 60 days demonstrated improved cognitive function compared to their sedentary counterparts. Gene activity changes were observed in both groups, but differed significantly between healthy mice and those modeling Alzheimer’s. In the Alzheimer’s model, exercise appeared to bolster the protective capabilities of the identified astrocyte subtype, cells which become less abundant as the disease progresses.
The findings align with broader observations linking exercise to reduced Alzheimer’s risk, improved cognitive function, and slower cognitive decline in individuals with the disease. A study published in February 2026, and reported by NPR, found that modest “mental exercise” could reduce dementia risk for decades, with participants in a cognitive speed training program in the 1990s showing a 25% lower likelihood of dementia diagnosis over the following 20 years.
Further research, published in April 2025 by Wake Forest University School of Medicine and University of California San Diego, indicated that even low-intensity exercise may sluggish cognitive decline in individuals at risk of Alzheimer’s. The EXERT study, a clinical trial involving sedentary older adults with mild cognitive impairment, found that both low and moderate-high intensity exercise groups exhibited stable cognitive function over 12 months, and less brain volume loss in key regions affected by Alzheimer’s, including the prefrontal cortex, compared to a control group.
A report from the Washington Post, published March 24, 2026, suggests exercise may strengthen a leaky blood-brain barrier, potentially improving brain health and fighting dementia. The National Institutes of Health reported in July 2025 that the research provides hints at possible future treatment strategies.