Semantic Memory Activation After Training Cessation In Master Athletes: 2283 Board #202 May 28 2:00 PM - 3:30 PM

PURPOSE: Despite a robust body of literature demonstrating the salutary effects of exercise on memory, we have yet to learn the link between exercise training cessation and memory in the aging brain. The aim of this study was to examine the effects of 10-day training cessation on semantic memory-related functional activation using task-activated functional magnetic resonance imaging (fMRI) in master athletes. METHODS: Twelve master athletes (62.6±7.0 years) with long-term endurance training histories (≥15 years), were recruited from Washington DC area running clubs. Participants were instructed to remain sedentary and perform only activities of daily living for 10 days. Before and immediately after the training cessation period, fMRI semantic memory activation was measured during performance of a Famous and Non-Famous name discrimination task. RESULTS: There were no significant differences in behavioral performance including response time and accuracy between pre- and post-training cessation. The 10-day training cessation was associated with greater semantic memory activation (Famous > Non-Famous) in five out of ten semantic memory-related regions (voxel-wise p < 0.001, FWE p < 0.05). CONCLUSIONS: The present results provide evidence that even a relatively short period of exercise training cessation results in changes in semantic memory network function and suggests reduced neural efficiency during memory retrieval. This study also indirectly indicates potentially detrimental effects of sedentary behavior in older adults and highlights the importance of sustained participation in exercise.