Abstract 13873: Arterial Stiffness in Response to Eight Weeks of Exercise Training in African Americans versus Caucasians

Abstract

Introduction: Arterial stiffness predicts risks of cardiovascular disease in apparently healthy individuals. Exercise training decreases risks of cardiovascular disease, potentially via reductions in arterial stiffness. Compared with Caucasians, African Americans have higher risks of cardiovascular disease. However, lack of evidence supports the beneficial effects of arterial stiffness in African Americans. We hypothesize that arterial stiffness decreases in African Americans following eight weeks of exercise training and the effect is similar compared with Caucasians. Methods: A total of 13 African American and 10 Caucasian men and women, free of cardiovascular disease participated this study (age: 38±2 yrs; body mass index: 31.0±1.1 kg/m 2 ; systolic blood pressures: 125±2 mmHg, diastolic blood pressure: 78±2 mmHg; mean±SE). Participants performed either aerobic exercise (65-85% of heart rate reserve) or resistance exercise (8-12 repetitions at 65-85% of 10-RM) for 30-45 minutes/time, three times/week for eight weeks. Arterial stiffness, assessed by carotid-to-femoral pulse wave velocity (cfPWV), and aortic blood pressure (BP) were measured by using the cuff-based SphygmoCor Xcel before and after the exercise training. Results: After the eight weeks of exercise training, cfPWV did not change in all participants, regardless of African Americans (6.7±0.3 vs. 6.5±0.3 m/sec; pre- vs. post-intervention) or Caucasians (6.3±0.4 vs. 6.0±0.3 m/sec; P=0.9 for raceхtime interaction, P=0.08 for time, and P=0.3 for race effect). Aortic systolic BP (African Americans: 123±5 vs. 120±3 mmHg and Caucasians: 111±2 vs. 110±3 mmHg; P=0.6 for raceхtime interaction, P=0.2 for time, and P=0.02 for race effect) and aortic diastolic BP (African Americans: 85±3 vs. 83±2 mmHg and Caucasians: 75±3 vs. 74±3 mmHg; P=0.6 for raceхtime interaction, P=0.5 for time, and P=0.01 for race effect) remained unchanged with the exercise training. Conclusions: An eight-week exercise training may not improve arterial stiffness in African Americans, and the effect appears to be similar in Caucasians.