The effects of HIIT compared to MICT on endothelial function and hemodynamics in postmenopausal females

Objective: The study was designed to investigate the role of exercise in ameliorating endothelial function and hemodynamics in postmenopausal females, and compare the different effects of high-intensity interval training and moderate-intensity continuous training by equalizing training load.Design: Randomized controlled trial.Methods: First intervention, 30 volunteers were randomized into low-intensity continuous training group or sedentary group. The low-intensity continuous training group was assigned to a 12-week training program at an intensity of 40% maximum heart reserve. The second intervention was an 8-week training program, in which 18 individuals were randomly placed either in the moderate-intensity continuous training or high-intensity interval training group. Flow-mediated dilatation, blood samples, carotid ultrasound, and wall shear stress were collected before, during, and after the interventions.Results: Flow-mediated dilatation was significantly increased in low-intensity continuous training group (p = 0.02), moderate-intensity continuous training (p = 0.023) and high-intensity interval training (p < 0.01) groups, with a time x group interaction for %FMD (F2, 32 = 4.421, p = 0.02), anda main effect of time (F2, 32 = 27.658, p < 0.001). Nitric oxide in low-intensity continuous training increased remarkably (p = 0.024) and was higher than that in control (p = 0.011). High-intensity interval training (p < 0.001) and moderate-intensity continuous training (p < 0.001) increased nitric oxide. Endothelin was decreased only in high-intensity interval training group (p = 0.049). All the training programs had a remarkable impact on wall shear stress.Conclusions: Low-intensity continuous training can improve endothelial function in postmenopausal females. High-intensity interval training could be an effective training regimen for improving endothelial function than moderate-intensity continuous training in postmenopausal females. (c) 2022 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.