Figure 4. Mediation Model.

After controlling for age and sex global longitudinal strain (GLS) showed a positive relationship with DMN CBF (path c; solid arrow) and a marginal positive relationship with cardiorespiratory fitness (path a). Cardiorespiratory fitness showed a positive relationship with DMN CBF (path b) and mediated the relationship between GLS and DMN CBF (c’; dashed arrow). Correlations coefficients are depicted with p-value superscripts for each path. Note: To render GLS-CBF relationships more interpretable, participant's GLS values were converted such that higher scores now reflected superior myocardial shortening mechanics (by multiplying each score by −1).