Exercise, Sleep, and Cognitive Performance in Older Adults: A Structured Review of Mechanisms and Clinical...

Background: Age-related cognitive decline is a major public health challenge, and modifiable lifestyle factors such as physical exercise and sleep have emerged as promising targets for preserving cognitive health. Our review aimed to synthesize evidence on the relationships between physical exercise, sleep, and cognitive performance in adults aged ≥60 years, with particular emphasis on the potential mediating or moderating role of sleep. Methods: Electronic searches were conducted in PubMed/MEDLINE, EMBASE, the Cochrane Library, Scopus, Web of Science, and Google Scholar to identify studies published between 2015 and 2025. Eligible studies evaluated structured exercise interventions or habitual physical activity and reported at least one sleep outcome alongside at least one cognitive outcome. Results: Twelve studies met the inclusion criteria, comprising randomized controlled trials, non-randomized intervention studies, and observational studies. Moderate-intensity aerobic exercise, multicomponent training, and mind-body interventions were the most frequently investigated exercise modalities. Across studies, exercise was generally associated with improved sleep quality and maintenance or enhancement of cognitive performance. Several studies identified sleep quality or sleep efficiency as potential mediators or moderators of exercise-related cognitive benefits; however, heterogeneity in study designs, interventions, sleep assessments, and cognitive outcomes precluded conclusions regarding causality. Conclusions: Current evidence suggests that sleep may represent an important behavioral pathway through which exercise contributes to cognitive health in older adults. Further well-designed randomized controlled trials incorporating objective sleep measures and mechanistic biomarkers are warranted to clarify these relationships.