Sex-specific Differences In Pulse Wave Reflection And Arterial Stiffness After Resistance Exercise

Abstract

Resistance exercise is recommended to improve fitness and to reduce the risk and severity of chronic diseases. Currently, no studies have evaluated sex differences in resistance-trained individuals in response to an acute bout of resistance exercise on pulse wave reflection and arterial stiffness. PURPOSE: We sought to determine sex-specific differences after an acute bout of free-weight resistance exercise on pulse wave reflection and arterial stiffness in resistance-trained individuals. METHODS: Resistance-trained men (n=14) and women (n=12) volunteered for the study. Aortic hemodynamics, pulse wave reflection and arterial stiffness were assessed in the supine position at rest and 10 minutes after an acute bout of free-weight exercise utilizing 3 sets of 10 repetitions at 75% 1-repetition maximum on the squat, bench press, and deadlift. Two minutes of rest was given between sets and exercises. An ANOVA was used to analyze the effects of sex across condition (acute resistance exercise or control) and time (rest and recovery). Paired t-tests were used for all post-hoc comparisons. RESULTS: The sexes had similar values at rest and after the acute resistance exercise such that there were no significant 3-way interactions. There were also no main effects of resistance exercise on brachial or aortic blood pressure. There were significant time by condition interactions for heart rate (rest: 61±9bpm; recovery: 89±13bpm, p=0.0001), augmentation index (rest: 12.1±7.9%; recovery:19.9±10.5%, p=0.003), augmentation index at 75bpm (rest: 5.3±7.9%; recovery: 24.5±14.3%, p=0.0001), augmentation pressure (rest: 4.9±2.8mmHg; recovery: 8.3±6.0mmHg, p=0.004), and pulse wave velocity (rest: 5.3±0.6ms; recovery: 5.9±0.7ms, p=0.02) such that they significantly increased after the acute resistance exercise. There were also significant time by condition interactions for time of the reflected wave (rest: 150±7ms; recovery: 147±9ms, p=0.02) and the subendocardial variability ratio (rest: 147±17%; recovery: 83±24%, p=0.0001) such that there were reduced after the acute resistance exercise. CONCLUSION: These data suggest that an acute bout of resistance exercise alters pulse wave reflection and arterial stiffness similarly between the sexes without significantly altering aortic hemodynamics.