Effect of Acute Aerobic Exercise on Arterial Stiffness in African Americans and Caucasians

Abstract

African-Americans (AA) have a higher prevalence of hypertension compared with their Caucasian counterparts(C). Measurement of central blood pressure (BP) has been suggested to hold greater prognostic capability than conventional brachial BP. PURPOSE: To compare central BP and brachial BP in AA and C following an acute maximal aerobic exercise. The secondary purpose was to evaluate potential factors realted to the changes. METHODS: Fifth-four healthy individuals (age 24±4.0years; 25 AA and 29 C) underwent measurements of aortic BP, brachial BP, radial applanation tonometry and carotid-femoral pulse wave velocity (central PWV) (Sphygmacor) at rest, 15 minutes post and 30 minutes post maximal aerobic exercise. Aortic BP, P1 and augmentation index at a heart rate of 75 beats/min ([email protected]) were derived from radial artery applanation tonometry. RESULTS:Table 1: Aortic BP, brachial BP, P1, central PWV and [email protected] pre, 15 minutes post and 30 minutes post exercise* Significant group-by-time interaction (P<0.05), # Significant time effect (P<0.05), Δ Significant group effect (P<0.05) CONCLUSIONS: Acute maximal aerobic exercise led to differential changes in aortic SBP without changes in brachial SBP between AA and C. Neither central PWV nor AIx is responsible for differential changes in aortic SBP. The reductions of aortic SBP during recovery phase maybe due to the decreases in P1 in both AA and C. Supported by NHLBI 1R01HL093249-01A1