O4‐13‐02: MID‐ AND LATE‐LIFE PHYSICAL ACTIVITY AND BRAIN AMYLOID DEPOSITION: THE ATHEROSCLEROSIS RISK IN COMMUNITIES (ARIC)‐PET STUDY. (1st July 2019) - Palta, Priya; Heiss, Gerardo; Walker, Keenan A.; Evenson, Kelly; Gabriel, Kelley Pettee; Mosley, Thomas H.; Gottesman, Rebecca F.