Walking over 3,000 steps a day may delay Alzheimer’s by years

Researchers from Harvard Medical School report that taking between 3,000 and 5,000 steps per day can delay the onset of memory and thinking problems by around three years, while walking 5,000 to 7,500 steps daily may extend that delay to as much as seven years.

The study followed 296 participants in the Harvard Aging Brain Study, a long-term project focused on the early biological signs of Alzheimer’s. All participants were between 50 and 90 years old and showed no signs of cognitive impairment when the study began. Over the course of up to 14 years, researchers conducted brain scans, memory tests, and step counts using pedometers to monitor their activity levels.

Participants who walked at least 3,000 steps per day (roughly equivalent to a 30-minute stroll) showed significantly slower cognitive decline than those who were mostly sedentary.

According to co-author Wai-Ying Wendy Yau, a physician-scientist specializing in memory disorders, the results challenge the popular notion that people need to take 10,000 steps daily to see health benefits.

“The very encouraging takeaway is that even a little bit of exercise seems to help,” Yau said.

How it works

Alzheimer’s disease is associated with the accumulation of two proteins (amyloid-β and tau) that disrupt brain function. Amyloid-β tends to build up first, followed by tau, which is more closely linked to cognitive decline.

The study found that regular walking specifically slowed the build-up of tau protein, even though it did not affect the increase of amyloid-β. This finding points to a possible mechanism by which exercise helps delay Alzheimer’s progression.

Interestingly, the protective effect of walking was observed only among participants who already had high levels of amyloid-β, indicating early biological signs of Alzheimer’s, but had not yet developed symptoms. Those with lower amyloid-β levels, and therefore a lower risk of developing the disease, did not see a measurable difference in cognitive outcomes based on their activity levels.

The researchers stress that while exercise alone cannot prevent Alzheimer’s, it appears to delay its clinical symptoms in those already showing early biological changes.

Earlier, Kazinform News Agency reported that men’s brains age faster, but women still face higher Alzheimer’s risk.