Objective: To examine whether engagement in physical activity might favorably alter the agedependent evolution of Alzheimer disease (AD)-related brain and cognitive changes in a cohort of at-risk, late-middle-aged adults. Methods: Three hundred seventeen enrollees in the Wisconsin Registry for Alzheimer’s Prevention underwent T1 MRI; a subset also underwent ¹¹C-Pittsburgh compound B–PET (n = 186) and […]