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bioRxiv · 10.1101/2022.07.15.500132

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

Palmer, J. A.·Morris, J. K.·Billinger, S. A.·Lepping, R. J.·Martin, L.·Green, Z.·Vidoni, E.
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Abstract

Over the course of aging, there is an early degradation of cerebrovascular health that 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 ([≥]65years) (n=60) using arterial spin labeling magnetic resonance imaging. Within 0-6 minutes 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 post-exercise 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 post-exercise. Gains in domain-specific cognitive performance post-exercise 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.

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Palmer, J. A., Morris, J. K., Billinger, S. A., Lepping, R. J., Martin, L., Green, Z., Vidoni, E.. 2022-07-16. Hippocampal blood flow rapidly and preferentially increases after a bout of moderate-intensity exercise in older adults with poor cerebrovascular health. https://doi.org/10.1101/2022.07.15.500132

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