The effect of physical activity on brain structure and cognitive function in the population-based cohort of LIFE-Adult-Study

Physical activity is thought to have a positive influence on brain health and cognition, and is considered a modifiable lifestyle factor that can protect against cognitive decline and neurodegeneration. In this observational study, we investigated the cross-sectional and longitudinal effects of self-reported total and moderate-to-vigorous physical activity on cognitive scores on the Trail Making Test (TMT-A and TMT-B), hippocampal volume, and BrainAGE, in a large population-based cohort from the LIFE-Adult Study (n = 2576). Furthermore, we examined the effect of objectively measured physical activity on brain structure in a subgroup with available accelerometry data (n = 227). Multiple linear regression analyses did not show any positive effects of self-reported or objectively measured physical activity on brain structure or cognitive function. Longitudinal path analyses indicated a possibility of reverse causation, whereby a higher BrainAGE at baseline was associated with lower physical capacity at follow-up. However, due to bias in self-report measures, definitive conclusions cannot be drawn, and further studies are needed to investigate the effects of physical activity on brain health.