Objective: Chronic stress has well-documented negative effects on hipocampal structure and function, and has been suggested to contribute to age-related declines. In contrast, there is evidence that exercise has beneficial effects in older adults. The current investigation examined effects of lifetime stress on hipocampal volume and memory, the moderating role of stress on age effects, and the moderating role of exercise on stress-related effects. Method:Measures of lifetime stress, exercise engagement, magnetic-resonance-imaging-based volumes, and cognitive performace were obtained in a sample of healtly middle-aged and older adults. Results: There was a significant negative influence of stress on hippocamal volume. In adition, exerciseengagement moderated effects of lifetime stress on buth hippocamal volume and memory. Specifically, lower exercise engagement individuals evidenced greater stress-related declines compared with high exercise in later adulthood may extend to minimizing detrimental effects os setress on the hippocampus and memory.
