New Delhi, November 2025: Staying physically active could be one of the most effective ways to protect the brain from age-related decline, especially for older adults at risk of Alzheimer’s disease, suggests a new study published in Nature Medicine on November 3.

Researchers from Mass General Brigham, Boston, led by Dr. Wai-Ying Wendy Yau, have found that older adults with elevated levels of amyloid—a key marker linked to Alzheimer’s disease—experienced slower cognitive and functional decline when they maintained higher levels of physical activity. The findings highlight the potential of exercise as a simple, non-drug strategy to help delay the progression of early Alzheimer’s changes in the brain.

The study measured physical activity using pedometers, tracking daily step counts in cognitively unimpaired older adults. Results showed that those who walked more had slower buildup of tau proteins in brain regions associated with memory and cognition, which in turn was linked to better cognitive outcomes over time. Interestingly, the benefits appeared to level off at moderate activity levels of about 5,000 to 7,500 steps per day—suggesting that one doesn’t need to engage in extreme exercise to reap cognitive benefits.

“Our findings support targeting physical inactivity as a strategy in future clinical trials to modify the trajectory of tau and cognition in preclinical Alzheimer’s,” the researchers noted. “This could also provide an easily attainable goal for older sedentary individuals at high risk of cognitive decline.”

While the study underscores a promising link between movement and mental resilience, the authors acknowledged that further randomized clinical trials are needed to confirm causation. Some of the researchers disclosed ties to the biopharmaceutical industry.

The study reinforces a growing body of evidence that even moderate physical activity—like brisk walking—can help preserve brain function and delay the onset of dementia-related symptoms in older adults.