Cerebral blood flow increases during light intensity aerobic exercise: a 4D flow MRI study

Motivation: Our current understanding of cerebral blood flow (CBF) during exercise is limited to extracranial assessments. Therefore, there is a need for precise measurements of intracranial blood flow during exercise using MRI. Goal(s): This research aimed to evaluate the impact of aerobic exercise on cerebral artery diameter and CBF. Approach: We utilized motion-robust 4D flow MRI to measure cerebral artery diameter and blood flow in multiple intracranial arteries at baseline and during light intensity aerobic exercise in young adults. Results: Light intensity exercise increased global CBF by 13% in part via increased left internal carotid artery and left middle cerebral artery diameter. Impact: Our findings generated new knowledge regarding intracranial blood flow during aerobic exercise. Future work may explore intracranial blood flow during exercise at various intensities to better understand the optimal stimulus for increasing cerebral blood flow.