Check out what we've been up to with our recently concluded projects!
Our research in cardiovascular, cerebrovascular, and exercise physiology has engaged with diverse populations across the lifespan and around the globe, from middle-aged adults with disease risk factors, to healthy adults trekking at high altitude to the base camp of Mt. Everest! Below is a brief summary of our recently concluded projects!
Aerobic Exercise Training and Brain Health in Middle-Age: The PulsATILE Trial (targeting cerebral Pulsatility through Aerobic exercise Training in mIddLe agE)?.
Healthy lifestyle behaviors (such as aerobic exercise) in middle age are critical to preserve brain health and prevent later-life Alzheimer’s disease and dementia, for which there is no known treatment. However, it is still unclear exactly how exercise “protects” the brain. Regular aerobic exercise (e.g. aerobic exercise training) may protect the brain by improving artery function and how blood flow is delivered to the brain, ultimately benefiting cognitive function. The purpose of this study was to compare the effects of 12 weeks of supervised aerobic exercise training versus a wait-list control group on brain blood flow, artery function, and cognitive function in middle-aged adults. This study was funded by Iowa State University College of Human Sciences and the findings were published in the Journal of Applied Physiology. The findings from this study suggested aerobic exercise training may lead to more immediate benefits in the central vasculature (e.g., the aorta), whereas longer duration exercise training may be required for beneficial changes in blood flow patterns within the brain.
Impact of a high-sugar mixed-meal on cerebrovascular function.
Many adults in the US regularly consume meals that are high in both fat and sugar, which may play a role in the development of obesity and type II diabetes and the accompanying risk of cerebrovascular and cognitive disease. PhD student Krista Reed lead a study examining how a single meal (high in both fat and sugar) acutely altered the function of the cerebral arteries to try and understand the mechanistic links between diet, type II diabetes, and brain health. The data from this study suggest that 1) the cerebrovascular response to a high-sugar mixed-meal may differ between segments of the extra- vs intra-cranial cerebrovasculature, and 2) middle-aged adults with cardiometabolic disease risk factors may have altered cerebrovascular responsiveness to a high-sugar mixed-meal compared to young, healthy adults. These findings are currently under consideration at a scientific journal.
Effects of Resistance Exercise Training on Depressive Symptomology and Cerebral Blood Flow in Adults with Depression.
The RESIST trial: "Resistance Exercise to Treat Major Depression via Cerebrovascular Mechanisms: Confirming Efficacy and Informing Precision Medicine" is funded by NIH NIHM (R01MH130566) and has concluded data collection at the Iowa State University site and the main clinical trial has been re-located to the University of Wisconsin-Madison with PI Dr. Jacob Meyer! Dr. Meyer and the team are continuing the work at UW-Madison and we will update this page with publications from the study as they develop! The protocol paper for the study can be found here.
Large artery and cerebral pulsatile hemodynamics during high altitude trekking in the Nepal Himalaya.
Hypoxia challenges the cardiopulmonary system to maintain oxygen delivery to the brain. The complex cardiovascular response to high altitude may change blood flow patterns in the brain, ultimately impacting oxygen delivery. We examined changes in large artery and cerebral pulsatile hemodynamics, and the potential sex-specific responses, during high-altitude sojourn in 17 young, healthy adults as part of a collaborative multi-institution research expedition to the Nepal Himalaya and Mt. Everest Base Camp. Our data suggest the potential for sex differences in the general reductions in cerebrovascular pulsatility with ascent to 4,300 m that likely stem from vasodilation and increases in cerebral blood flow. Data from this study are currently under consideration at a scientific journal. Undergraduate students Carolyn Steffen and Abby Burkhart joined Dr. Lefferts to collect the data and enjoy the perks of high altitude testing. A compilation video of the expedition is below! We plan is to put together another research expedition to Mt. Everest base camp from Iowa State University with Iowa State students in ~2027.