THE EFFECTS OF AEROBIC EXERCISE INTENSITIES ON CENTRAL BLOOD PRESSURE IN OVERWEIGHT AND OBESE AFRICAN AMERICANS

Abstract

African Americans are at an increased risk of cardiovascular disease and type 2 diabetes compared to their Caucasian counterparts. According to the 2018 American Heart Association report, nearly half of all African American adults (46.0% of males & 47.7% of females) show prevalence of cardiovascular disease. From these health disparities, studies have found that African American adults have a significantly higher prevalence of risk factors for cardiovascular disease and mortality including: hypertension, obesity, inactivity, and smoking. The American College of Sports Medicine guidelines recommend that adults participate in 150 minutes of moderate intensity aerobic activity each week or 75 minutes of vigorous intensity aerobic activity each week for improvement of health-related risk factors. Most studies assessing the benefits of exercise at different intensity levels were performed in mostly Caucasian populations. Hypertension is one of the most prominent risk factors for cardiovascular disease and mortality. Brachial blood pressure is the typical method for assessing hypertension; however, recent studies suggest that aortic blood pressure may be a better indicator of future cardiovascular events. Many studies have shown that aerobic exercise can reduce mean systolic and diastolic brachial blood pressure. Additionally, research assessing aortic blood pressure have found a reducing effect of aerobic exercise on systolic and diastolic pressure; however, the majority of these studies consisted of primarily Caucasian adults. Considering the increased risk of cardiovascular disease and type 2 diabetes among African American adults, more research assessing the effects of moderate and high intensity aerobic exercise on specific risk factors in African American Adults is clinically important. It is possible that high intensity exercise training may result in a greater reduction in central blood pressure compared to moderate intensity exercise due to the greater shear stress on the vasculature. The purpose of this study is to evaluate the effect of exercise training intensity on central blood pressure in overweight and obese African Americans. Participants (n=60) will complete 6 months of supervised exercise training at either moderate (45-55% VO2 max) or high (70-80% VO2 max) intensity. Central blood pressure will be assessed at baseline and follow up using the AtCor SphygmoCor Xcel.