The Effects of an Acute Bout of Resistance Training on Aortic Hemodynamics

Abstract

INTRODUCTION: Health organizations recommend aerobic and resistance exercise to improve cardiovascular health. Acute aerobic exercise causes a prolonged decrease in aortic blood pressure and metrics of arterial wave reflection, but the prolonged effects of acute resistance training are not as well understood. The purpose of this study was to determine the prolonged effect of a single bout of resistance exercise on arterial wave reflection magnitude, timing, and wasted pressure effort. METHODS/DESIGN: Twenty healthy, young adults (n = 7, women) participated in this study. Radial artery applanation tonometry and echocardiography were performed to estimate aortic pressure wave morphology and left ventricular outflow, respectively, for subsequent pressure-flow analyses. Participants completed 8 (4 upper and 4 lower body) machine-based exercises (8-12 reps, 2 sets each, at 60-70% of 1-RM). Then had measurements repeated at 30-, 60-, 90-, and 120-minutes post-exercise. Data was analyzed using repeated measures with Dunnet adjustment when appropriate for post-hoc comparisons. RESULTS: Compared to baseline, reflection magnitude decreased at 30- and 60-minutes post-exercise (baseline 41 ± 6%; vs. 30-min post 34 ± 7%, p = 0.03; vs. 60-min post 37 ± 8%, p = 0.03). Compared to baseline, wasted pressure effort decreased at 60-, 90-, and 120-minutes post-exercise (baseline 2150 ± 672 mmHg • ms; vs. 60-min post 1693 ± 746 mmHg • ms, p <0.001; 90-min post 1713 ± 859 mmHg • ms, p < 0.01; 120-min post 1700 ± 561 mmHg • ms, p < 0.01). Compared to baseline, wasted pressure effort relative to the product of characteristic impedance and flow ratio also decreased at 60-, 90-, and 120-minutes post-exercise (baseline 0.37 ± 0.08; vs. 60-min post 0.29 ± 0.14, p < 0.01; 90-min post 0.28 ± 0.14, p < 0.01; 120-min post 0.29 ± 0.13, p < 0.01). CONCLUSION: An acute bout of full-body resistance exercise improves indices of arterial wave reflection, specifically wasted pressure effort, up to at least 2 hours post-exercise in healthy young adults.