Fig. 1
From: Association between cardiorespiratory fitness and total brain myelin volume among older adults
Association between myelin compound and cardiorespiratory fitness. (a) RERmax vs. MYC/ICV, (b) RERmax vs. MYC/BPV (c) HRmax vs. MYC/ICV, (d) HRmax vs. MYC/BVP. Both, the proportions of myelin relative to intracranial volume and brain parenchymal volume MyC/ICV and MyC/BPV show a consistent moderate positive correlation with the respiratory exchange ratio (RERmax) and a negative correlation with maximal heart rate (HRmax)