Long-term physical exercise facilitates putative brain waste clearance flow in humans

Motivation: The glymphatic system and meningeal lymphatic vessels(mLV) are essential for clearing brain waste linked to neurodegenerative diseases. Although animal studies suggest that regular exercise enhances glymphatic function, human studies on long-term exercise's effect on brain clearance remain limited. Goal(s): This study aims to evaluate the effects of long-term exercise on glymphatic and mLV flow in humans. Approach: We employed dynamic T1 mapping, black-blood imaging, and IR-ALADDIN techniques to measure brain waste clearance in healthy volunteers with single-bout or long-term exercise. Results: Long-term exercise significantly increased putative glymphatic influx and putative parasagittal mLV flow, highlighting the potential benefits of exercise on brain waste clearance. Impact: The results demonstrate that long-term exercise can enhance glymphatic and mLV flow, which may underlie the neuroprotective effects of exercise. These findings could lead to new interventions for preventing neurodegenerative diseases by enhancing brain waste clearance mechanisms.