Abstract
BACKGROUND: Physical activity (PA) engagement declines with age in late adulthood. Therefore, understanding factors underlying PA engagement is needed for PA promotion in older adults. Executive function is a potential key neurocognitive resource that supports PA engagement. The current study aims to provide neurobiological evidence for this hypothesis by examining the role of the executive function networks in PA engagement. METHODS: Resting-state functional magnetic resonance imaging data and self-reported PA engagement were obtained from the Cambridge Centre for Ageing and Neuroscience (Cam-CAN; age range 18-81). The frontoparietal network and salience network were chosen as networks of interest. RESULTS: We found that PA engagement began to decline at the age of 49 via piecewise regression. Meanwhile, functional connectivity within frontoparietal network connecting posterior cingulate, parietal area, and precuneus, and functional connectivity within salience network connecting right temporo-parieto-occipital area, anterior and middle cingulate, and bilateral fronto-operculum and insula were associated with PA. The PA-associated functional connectivity within salience network mediated the age-related decline of PA engagement, which was not observed for the frontoparietal network. CONCLUSIONS: Physical activity engagement begins to decrease in middle-age, while functional connectivity between key regions related to inhibitory control and behavior regulation is a potential neural mechanism underlying this age-related decline. These findings provide neurobiological evidence for the hypothesis that aspects of executive function support PA engagement. Moreover, it also identifies potential neural targets for future PA promotion interventions.