Physical inactivity, a modifiable risk factor for Alzheimer’s disease (AD), has been implicated in influencing disease progression; however, its direct relationship with AD pathology in humans remains insufficiently understood. To address this gap, a study examined the association between pedometer-measured physical activity and cognitive outcomes involving 296 cognitively unimpaired participants aged 50–90 years. The study found that higher physical activity was linked to slower amyloid-related inferior temporal tau accumulation, which mediated slower cognitive decline. Importantly, this effect was independent of baseline or longitudinal amyloid burden.
Dose–response analyses revealed a plateau in benefits at moderate activity levels, i.e. 5,001–7,500 steps/day, suggesting an attainable target for older sedentary adults. These findings suggest that targeting sedentary individuals with…
