Impact Of Acute Cycling Exercise On Emotional Processing In Healthy Older Adults

The well-elucidated mood-improving capability of exercise in older adults presumably involves adaptations after each exercise session in brain networks that process emotion. However, little is known about effects of acute exercise on appetitive and aversive emotion-related network recruitment in older adults. PURPOSE: To determine the effect of acute exercise on pleasant and unpleasant emotion-related regional activation in healthy older adults, compared to a seated rest condition. METHODS: Functional MRI data were acquired in 31 active older adults during blocked presentations of pleasant, neutral, and unpleasant images from the International Affective Pictures System. fMRI data were collected after participants completed 30-minutes of moderate intensity cycling and after a 30-minute seated rest condition - performed in a counterbalanced order on separate days in a within-subjects design. Activation to pleasant and unpleasant stimuli were expressed relative to neutral stimuli (FWER p < .05). RESULTS: After acute exercise compared to after rest, there was increased subjective positive affect coupled with significantly less pleasant activation at the bilateral precuneus, significantly less unpleasant activation at the bilateral fusiform gyrus and inferior temporal gyrus, and significantly more unpleasant activation at the bilateral medial superior frontal gyrus, angular gyri, supramarginal gyri, a portion of right dorsolateral prefrontal cortex, and regions of the left cerebellar cortex. CONCLUSION: For active older adults, acute exercise may influence emotional activation via various candidate mechanisms. For pleasant emotion processing, reduced precuneus activation may reflect reduced emotional regulation. When facing unpleasant stimuli, findings may reflect reduced recruitment of aversive motivational circuits, coupled with greater recruitment of frontal cortical regions known to inhibit subcortical limbic networks.