Hippocampal blood flow rapidly and preferentially increases after a bout of moderate-intensity exercise in older adults with poor cerebrovascular health

• Published in: Cerebral cortex (New York, N.Y. 1991) N.Y. 1991), 2023-04, Vol.33 (9), p.5297-5306
• Main Authors: Palmer, Jacqueline A, Morris, Jill K, Billinger, Sandra A, Lepping, Rebecca J, Martin, Laura, Green, Zachary, Vidoni, Eric D
• Format: Article
• Language: English
• Subjects: Aged; Cerebrovascular Circulation - physiology; Exercise - physiology; Hemodynamics; Hippocampus; Humans; Magnetic Resonance Imaging - methods; Original
• ISSN: 1047-3211; 1460-2199
• DOI: 10.1093/cercor/bhac418

Abstract Over the course of aging, there is an early degradation of cerebrovascular health, which may be attenuated with aerobic exercise training. Yet, the acute cerebrovascular response to a single bout of exercise remains elusive, particularly within key brain regions most affected by age-related disease processes. We investigated the acute global and region-specific cerebral blood flow (CBF) response to 15 minutes of moderate-intensity aerobic exercise in older adults (≥65 years; n = 60) using arterial spin labeling magnetic resonance imaging. Within 0–6 min post-exercise, CBF decreased across all regions, an effect that was attenuated in the hippocampus. The exercise-induced CBF drop was followed by a rebound effect over the 24-minute postexercise assessment period, an effect that was most robust in the hippocampus. Individuals with low baseline perfusion demonstrated the greatest hippocampal-specific CBF effect post-exercise, showing no immediate drop and a rapid increase in CBF that exceeded baseline levels within 6–12 minutes postexercise. Gains in domain-specific cognitive performance postexercise were not associated with changes in regional CBF, suggesting dissociable effects of exercise on acute neural and vascular plasticity. Together, the present findings support a precision-medicine framework for the use of exercise to target brain health that carefully considers age-related changes in the cerebrovascular system.