Pathophysiological changes in cerebrovascular reactivity can remain undetectable at rest, and may only become apparent during a cerebrovascular challenge. We evaluated the feasibility of dynamically measuring the cerebrovascular response to exercise using pseudo-continuous arterial spin labeling (pCASL) at 3 Tesla during a bicycle exercise-recovery stress test. We observed a transient increase in cerebrovascular blood flow (CBF) during exercise in four volunteers, demonstrating that pCASL-MRI can capture dynamic changes in CBF during physiological bicycle exercise. This approach may become an important quantitative tool to noninvasively investigate the cerebrovascular reactivity in health and disease.