Aerobic exercise improves episodic memory in late adulthood: a systematic review and meta-analysis

Background: Aerobic exercise remains one of the most promising approaches for enhancing cognitive function in late adulthood, yet its potential positive effects on episodic memory remain poorly understood and a matter of intense debate. Prior meta-analyses have reported minimal improvements in episodic memory following aerobic exercise but have been limited by restrictive inclusion criteria and infrequent examination of exercise parameters. Methods: We conducted a meta-analysis of randomized controlled trials to determine if aerobic exercise influences episodic memory in late adulthood (M = 70.82 years) and examine possible moderators. Thirty-six studies met inclusion criteria, representing data from 2750 participants. Results: Aerobic exercise interventions are effective at improving episodic memory (Hedges’ g = 0.28; p = 0.002). Subgroup analyses revealed a moderating effect of age (p = 0.027), with a significant effect for studies with a mean age between 55–68 but not 69–85. Mixed-effects analyses demonstrated a positive effect on episodic memory among studies with a high percentage of females (65–100%), participants with normal cognition, studies reporting intensity, studies with a no-contact or nonaerobic physical activity control group, and studies prescribing >3900 total minutes of activity (range 540–8190 min). Conclusions: Aerobic exercise positively influences episodic memory among adults ≥55 years without dementia, with larger effects observed among various sample and intervention characteristics—the clearest moderator being age. These results could have far-reaching clinical and public health relevance, highlighting aerobic exercise as an accessible, non-pharmaceutical intervention to improve episodic memory in late adulthood.

Sarah L. Aghjayan, Themistokles Bournias, Chaeryon Kang, Xueping Zhou, Chelsea M. Stillman, Shannon D. Donofry, Thomas W. Kamarck, Anna L. Marsland, Michelle W. Voss, Scott H. Fraundorf, Kirk I. Erickson