Physical Activity, Exercise Physiology, Movement
The Effects of Exercise Training Cessation on Cerebral Blood Flow: An Arterial Spin Labeling Analysis
(School of Public Health (UMD) KNES Doctoral Student)
Objective: While exercise is known to improve cerebrovascular health, it is not known how a short-term cessation of regular exercise training may impact brain health. Our aim was to measure changes in resting cerebral blood flow (CBF) after a 10-day cessation of exercise training in healthy physically fit older adults. Participants/Methods: Ten master athletes (men=7), defined as 50 years of age or older with a 15-year history of endurance exercise training, were recruited from local running clubs. Criteria for endurance exercise training included four training sessions, and at least four hours of high intensity exercise, per week. Before and immediately after the 10-day cessation of exercise training, CBF was measured using interleaved, multi-sliced, perfusion weighted magnetic resonance imaging. Paired T-tests were used to assess CBF changes over time. Results: We found that a 10-day cessation of exercise training altered CBF in several brain areas with general decreases in the frontal, temporal, and parietal lobules (p<0.05). The strongest alterations were decreases in the bilateral precuneus and right cerebellar tonsil; and increases in the right insula and superior temporal gyrus (p<0.01). Additional decreases also were found in the left thalamus, bilateral posterior cingulate, and parahippocampal gyri (p<0.05). Conclusions: The cessation of exercise training for a period of 10-days in healthy physically fit older adults resulted in decreased resting parenchymal blood flow in several brain regions. This suggests that the cerebrovascular system may be very responsive to the effects of exercise, and that even short-term decreases in exercise training in healthy older adults may reverse these effects.