Over the past decade, we have recognized that brain changes do not begin when cognitive symptoms appear. In Alzheimer’s disease (AD) and related dementias, the underlying pathophysiological processes may develop silently over many years, and cerebrovascular dysfunction is likely to be one of the earliest abnormalities. This perspective shaped a primary question of our recent study: can exercise improve cerebrovascular function in individuals who have high risks of developing AD?
Blood flow to the brain is essential for maintaining neuronal health and cognitive function. However, brain health also depends on how effectively the cerebrovascular system buffers the pulsatile energy generated by each heartbeat. When that buffering capacity is impaired, the damage may be subtle at first, but repeated mechanical stress over time may gradually injure the cerebral microvasculature—much like constant dripping wearing away stone.
In our earlier work, we found that patients with aMCI had higher cerebrovascular impedance than cognitively normal older adults, suggesting impaired pulsatile buffering in this at-risk population for AD. That finding led to the next question for our study: can this abnormality in cerebrovascular function be ameliorated? To address this question, we conducted a one-year randomized controlled trial in patients with aMCI, comparing aerobic exercise training with a stretching-and-toning program. Over time, participants in the aerobic exercise group showed a progressive reduction in cerebrovascular impedance, and importantly, this improvement was accompanied by higher brain blood flow and greater cerebrovascular conductance, indicating a more favorable cerebral hemodynamic environment for brain health. In contrast, although stretching and toning produced modest reductions in cerebrovascular impedance, it did not improve brain blood flow, suggesting that aerobic exercise is more effective in improving cerebrovascular function than stretching and toning.
For clinicians, patients with aMCI present a critical time window for intervention. At this time, treatment options for AD remain limited, and prevention or slow of disease progression is paramount. Our findings suggest that aerobic exercise improves cerebrovascular function, which has been linked directly to reductions in cognitive decline in older adults with high risk of AD. For researchers, these results highlight the importance of looking beyond static measures such as resting brain blood flow. The interaction between pressure and flow—how the system behaves dynamically—may provide deeper insight into brain vascular and neuronal health as well as neurodegenerative disease progression. For exercise professionals, the message is clear: sustained aerobic training plays a central role in maintaining brain vascular health. Importantly, these vascular benefits develop over time, reinforcing the value of long-term adherence rather than short-term interventions.
More broadly, our findings align with the concept that effects of exercise on brain health are likely to be cumulative. Rather than acting as a short-term intervention, sustained engagement in aerobic activity promotes vascular and brain health across the lifespan. In this context, exercise should not be viewed simply as an adjunct strategy. It is fundamental in preserving brain health by engaging vascular pathways that are essential for brain structural and functional integrity. Future studies are needed to determine the underlying biological mechanisms by which these vascular improvements translate into long-term cognitive outcomes and how exercise prescriptions can be optimized for individuals.
Jun Sugawara, PhD, FACSM, is a team leader at the Integrated Research Center for Self-Care Technology, National Institute of Advanced Industrial Science and Technology (AIST), and a professor in the Institute of Health and Sports Sciences, University of Tsukuba,Japan. His research focuses on vascular mechanisms underlying cardiovascular aging, exercise responses, and physiological resilience.
Rong Zhang, PhD, is a professor in the Departments of Neurology, Internal Medicine, and Biomedical Engineering at UT Southwestern Medical Center and the director of Cerebrovascular Laboratory at the Institute for Exercise and Environmental Medicine, Texas Health Presbyterian Hospital Dallas. He is a member of ACSM and principal investigator on multiple NIH-funded studies of vascular mechanisms underlying brain aging and neurological disease.
