Effects of Aerobic Exercise on Brain Age and Health in Older Adults: A Single-Arm Clinical Trial

BackgroundsExercise is an attractive, widely accessible intervention to promote cardiovascular health; however, evidence that exercise improves brain health is sparse. Here, we hypothesized that aerobic exercise would improve brain health of sedentary older adults, as reflected by cognition health, sleep macro- and micro-architecture, and brain age index (BAI), a biomarker of brain health derived from the overnight sleep electroencephalogram (EEG). MethodsSedentary older adults were recruited to complete a 12-week aerobic exercise. Home wearable devices were used to monitor heart rate and overnight sleep EEG over the period. NIH Toolbox Cognition Battery, in-lab overnight polysomnography, cardiopulmonary exercise testing and multiplex cytokine assay were employed to determine pre- and post-exercise brain health, exercise capacity and plasma proteins. Results26 participants completed the initial assessment and exercise program, and 24 completed all procedures. Participants significantly increased maximal oxygen consumption (VO2max) and decreased resting and sleeping heart rate after the exercise regimen. Cognition performances were significantly improved following the exercise program while no significant differences were seen in BAI and sleep macro- and micro-architecture. Plasma IL-4 was elevated while IL-8 was reduced after the exercise regimen. Home sleep data revealed a 3.59% increase in the percentage of N3 sleep over a 12-week. ConclusionsWe conclude that cognitive function and N3 sleep were improved by a 12-week moderate-intensity exercise program in sedentary older adults, associated with improvements in VO2max and plasma cytokine profiles. Our data show the value of integrating multi-modal assessments to study the effect of brain health targeted approaches. FundingDr. Westover received support during this work from the McCance Center for Brain Health, the Glenn Foundation for Medical Research and the American Federation for Aging Research through a Breakthroughs in Gerontology Grant; through the American Academy of Sleep Medicine through an AASM Foundation Strategic Research Award; by the Football Players Health Study (FPHS) at Harvard University; from the Department of Defense through a subcontract from Moberg ICU Solutions, Inc, and by grants from the NIH (R01NS102190, R01NS102574, R01NS107291, RF1AG064312, R01AG062989, R01AG073410), and NSF (2014431). Dr. Wrann was supported by a SPARC Award from the McCance Center for Brain Health. Dr. Tanzi and Dr. Zhang were supported by the Cure Alzheimers Fund. Clinical trial numberNational Clinical Trial: NCT04210882 One Sentence SummaryWe observed that exercise improved slow wave sleep, increased circulating neuroprotective cytokines and improved cognition health in older adults.