Arterial Compliance Response To Aerobic Exercise With and Without Blood Flow Restriction In Pre-hypertensive Males

Abstract

PURPOSE: The aim of the study was to assess the effects of acute aerobic exercise with and without blood flow restriction on arterial compliance in pre-hypertensive males. METHODS: Ten pre-hypertensive male subjects (age= 23.1±3.2) performed two randomized exercise sessions. Anthropometric measurements, questionnaires, and Bruce protocol were completed at screening. Baseline measurements were obtained each testing day following subjects reaching a normal hydration status. Subjects then ran at 65% VO2 for a 60 min or 20 min at 40% VO2 with blood flow restriction (BFR). Arterial elasticity was measured at 0, 10, 20, and 40 minutes and pulse wave velocity (PWV) was measured at 5, 15, 25, and 35 minutes post-exercise. RESULTS: There were no significant condition*time interactions or no main effects for condition and time for carotid to radial, carotid to femoral, femoral to distal PWV, small (SAE) or large arterial elasticity (LAE). Significant condition*time interaction (p<.03) and time main effect (p<.01) were found in systolic blood pressure (p<.03). There were also significant condition*time interaction (p<.03) and condition main effect (p<.03, BFR higher) in diastolic blood pressure (p<.03). Significant condition*time interaction (p<.01) and condition (p<.01, 60 min higher) and time main effects (p<.01) were found in heart rate (HR). Significant condition*time interaction (p<.01) and condition (p<.05, BFR higher) and time main effects (p<.01) were found in stroke volume (SV). Significant condition*time interaction (p<.01) and time main effects (p<.02) were found in cardiac output (CO). Significant condition*time interaction (p<.01) and condition (p<.01, 60 min lower) and time main effects (p<.02) were found in systemic vascular resistance (SVR). A significant condition main effect for total vascular impedance (TVI) was detected (p<.05, 60 min lower). CONCLUSIONS: Since subjects were in supine position for post-testing, significantly lower SV values could be due to lower venous return and/or sweat-related blood volume loss and lower SVR and TVI could be because of endothelium derived nitric oxide following the 60 min session. The findings also indicate that the 20 min with BFR session may not be intense and/or long enough to cause significant changes in variables tested.