HIIT, Sleep and Cognition in Older Adults

Abstract Background Sleep disturbances have been linked to cognitive and physical decline in older adults. High-intensity interval training (HIIT) may resynchronize disrupted sleep-wake cycles, improve sleep quality, and potentially delay detrimental impacts of aging on cognition and physical performance. Methods A systematic review using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) approach to evaluate the impacts of HIIT upon sleep and cognition. Results Data from 158 participants with median age of 69.5 years from four randomized controlled trials were analyzed, including comparison groups. HIIT improved sleep quality, reduced sleep onset latency, and lowered wake after sleep onset compared to sedentary and regular physical activity. However, HIIT outcomes on sleep quality were not significantly different from the benefits of stretching exercise and moderate-intensity physical activity. In addition, only one study (two publications) looked into the impacts of HIIT on both sleep and cognition, indicating improvement in cognitive performance and memory. Conclusion Despite the potential for HIIT to improve sleep quality, more studies are warranted, particularly those that include diverse populations and larger sample sizes prior to forming recommendations for use in clinical settings and communities. However, separate studies have identified that HIIT improves memory and cognitive function and future studies could also elucidate biomarkers for sleep and cognition.