Abstract:
Exercise is effective in improving cardiovascular health, specifically, as a result of the increase shear stress on peripheral vasculature. Similarly, heat therapy (i.e., sauna bathing and hot water immersion) has indicated similar responses to exercise on endothelial function and vascular remodeling. However, less is understood about the peripheral vascular responses of a single bout of cold-water immersion and if it could be used as an alternative to exercise to improve cardiovascular health. Therefore, the purpose of this study was to test the hypothesis that cold-water immersion results in peripheral vascular changes that may be beneficial to overall cardiovascular health (i.e., increase in shear stress through increased blood flow). Eight young, healthy adults (4 self-reporting male and 4 self-reporting females: age: 24±7 years; height: 172±39 cm; weight: 65±24 kg; and BMI: 22.2±7.9 kg/m2) completed one study visit where they were immersed to the sternum in ~10C water for 15 minutes. Ultrasound imaging of the brachial artery was taken prior to, during, and after the cold-water immersion. Our results indicate there was a decrease in brachial artery diameter during and after cold-water immersion, and blood flow and shear decreased during the post-immersion recovery period in comparison to pre-immersion. Therefore, this may indicate a negative effect on peripheral vascular function; future research should focus on these peripheral vascular changes with repeated bouts of cold-water immersion