Effect Of High Intensity Interval Training On Vascular Endothelial Function In Postmenopausal Women

Objective: This study compares and analyzes the changes in vascular endothelial function,blood flow shear force and blood,etc.,in between high-intensity intermittent training group and aerobic exercise group,before exercise,after 4 weeks of exercise and after 8 weeks of exercise.The study explores the improving effect of high-intensity intermittent training on vascular endothelial function and the related mechanism on how exercise improve vascular endothelial function.Methods: 20 healthy menopausal women with endothelial dependent brachial artery diastolic function less than 10% were randomly divided into high intensity interval training group and aerobic exercise group.High intensity interval training was performed with 85%-95% maximum heart rate intensity for 4 minutes,60%-70%maximum heart rate for 3 minutes interval exercise,repeated 4 groups,3 times a week for 8 weeks.Aerobic exercise was performed with 60%-70% sustained exercise for 40 minutes,3 times a week for 8 weeks.Endothelial dependent brachial artery diastolic function,wall shear stress,nitric oxide were measured before exercise,4weeks after exercise and 8 weeks after exercise.Endothelial factors such as endothelin 1,angiotensin II and total cholesterol,triglycerides,high-density lipoprotein cholesterol,low-density lipoprotein cholesterol were detected by SPSS23.0 statistical software.Results: The endothelial-dependent brachial artery diastolic function(18.1±4.6%)was significantly higher in the high intensity interval training group than in the aerobic exercise group(11.3±1.5%)after 8 weeks high intensity interval training and aerobic exercise.Nitrous oxide(59.7±9.8μmol/L)was significantly higher in the high intensity interval training group than in the aerobic exercise group(54.3±8.1μmol/L).the endothelin-1(20.4±8.6pg/ml)in the high-intensity interval training group was significantly higher than that in the aerobic exercise group(18.0±4.4 pg/ml);the wall shear stress(19.31±0.94 dynes/cm~2)in the high-intensity interval training group was significantly higher than that in the aerobic exercise group(17.53±2.77 dynes/cm~2);and there was no significant difference in the indexes of angiotensin,total cholesterol,triglyceride,high-density lipoprotein cholesterol,low-density lipoprotein cholesterol and so on.There was a significant correlation between endothelial-dependent brachial artery diastolic function and nitric oxide level after 8 weeks of intensive interval training(P<0.01,r=0.441),endothelial-dependent brachial artery diastolic function and endothelin 1 level(P<0.01,r=-0.470),and endothelial-dependent brachial artery diastolic function and angiotensin level(P<0.05,r=-0.310).A significant correlation was found between changes in diastolic function and wall shear stress(P<0.01,r=0.482).Conclusion: 1.Eight weeks of high intensity intermittent training can improve vascular endothelial function in menopausal women,and this intensity intermittent training can improve vascular endothelial function in menopausal women better than aerobic exercise.2.Eight weeks of exercise may improve vascular endothelial function by changing wall shear stress and nitric oxide.