Title : The association between cardiorespiratory fitness and white matter integrity across the lifespan: A meta-analytic review
Abstract:
White matter deterioration is a hallmark of cognitive aging and a core feature of many neurodegenerative disorders. Cardiorespiratory fitness (CRF) has emerged as a modifiable factor that may support white matter integrity across the adult lifespan. This meta-analytic review synthesized findings from seven peer-reviewed studies examining the association between objectively measured CRF and neuroimaging-based white matter structure. Results revealed a consistent positive relationship between higher CRF and stronger microstructural integrity, particularly in late-myelinating tracts such as the corpus callosum, cingulum, and longitudinal fasciculi. These associations were more robust in adults over 60, suggesting age-dependent neuroprotective effects. Higher CRF was also linked to reduced white matter hyperintensity (WMH) burden in older populations. Although most included studies were cross-sectional, one randomized trial provided intervention-based evidence of white matter plasticity. These findings underscore the potential of CRF as a non-pharmacological strategy to preserve brain health and mitigate cognitive decline with age. Future research should adopt longitudinal and multimodal designs to clarify causal mechanisms and identify moderators of these effects.