Overview
- The peer‑reviewed study, published November 3 in Nature Medicine, analyzed a Harvard/Mass General Brigham cohort of 296 older adults followed for up to 14 years, including 88 with preclinical Alzheimer‑type brain changes.
- Baseline seven‑day pedometer readings were linked to slower tau accumulation on PET scans and to less cognitive decline on annual testing.
- Approximately 3,000 steps per day—about 30 minutes of walking—was associated with delaying disease progression by up to three years.
- Associations were stronger between roughly 5,000 and 7,500 steps per day, with little additional benefit observed beyond that range.
- Authors and independent experts caution the findings are observational, note step counts were measured only once, and call for replication before drawing causal conclusions.