Shenouda Ninette, Skelly Lauren E, Gibala Martin J, MacDonald Maureen J
Department of Kinesiology, McMaster University, Hamilton, ON, Canada.
Exp Physiol. 2018 Jul;103(7):968-975. doi: 10.1113/EP086677. Epub 2018 May 30.
What is the central question of this study? What is the acute brachial artery endothelial function response to sprint interval exercise and are there sex-based differences? What is the main finding and its importance? Brachial artery endothelial function did not change in either men or women following an acute session of SIT consisting of 3 × 20 s 'all-out' cycling sprints. Our findings suggest this low-volume protocol may not be sufficient to induce functional changes in the brachial artery of sedentary, but otherwise healthy adults.
Sprint interval training (SIT) is a potent metabolic stimulus, but studies examining its acute effects on brachial artery endothelial function are limited. The influence of oestradiol on the acute arterial response to this type of exercise is also unknown. We investigated the brachial artery endothelial function response to a single session of SIT in sedentary healthy men (n = 8; 22 ± 4 years) and premenopausal women tested in the mid-follicular phase of the menstrual cycle (n = 8; 21 ± 3 years). Participants performed 3 × 20 s 'all-out' cycling sprints interspersed with 2 min of active recovery. Brachial artery flow-mediated dilatation (FMD) and haemodynamic parameters were measured before and 1 and 24 h post-exercise. Despite attenuations in some haemodynamic parameters at 1 h post-exercise, there were no changes in absolute (P = 0.23), relative (P = 0.23) or allometrically scaled FMD (P = 0.38) following a single session of SIT. Resting and peak dilatory diameters did not change in men or women (P > 0.05 for all) and there were no interactions between time and sex for any measure (P > 0.05). Oestradiol was not correlated with relative FMD at baseline (r = -0.22, P = 0.42) or with the change in relative FMD from baseline to 1 h post-exercise (r = 0.24, P = 0.40). Overall, brachial artery FMD appears to be unchanged in men and women following an acute session of SIT, and the higher oestradiol concentrations in women do not augment the baseline or post-exercise FMD response. The 3 × 20 s model of low-volume sprint interval exercise may not be sufficient to alter brachial artery endothelial function in healthy men and women.
本研究的核心问题是什么？急性短跑间歇运动对肱动脉内皮功能有何反应，是否存在性别差异？主要发现及其重要性是什么？在由3组×20秒“全力”骑行冲刺组成的急性短跑间歇训练（SIT）后，男性和女性的肱动脉内皮功能均未改变。我们的研究结果表明，这种低运动量方案可能不足以在久坐但健康的成年人肱动脉中诱导功能变化。
短跑间歇训练（SIT）是一种强大的代谢刺激，但研究其对肱动脉内皮功能急性影响的研究有限。雌二醇对这类运动急性动脉反应的影响也未知。我们调查了久坐的健康男性（n = 8；22±4岁）和处于月经周期卵泡中期的绝经前女性（n = 8；21±3岁）单次SIT后肱动脉内皮功能的反应。参与者进行了3组×20秒的“全力”骑行冲刺，中间穿插2分钟的主动恢复。在运动前、运动后1小时和24小时测量肱动脉血流介导的舒张（FMD）和血流动力学参数。尽管运动后1小时某些血流动力学参数有所下降，但单次SIT后绝对（P = 0.23）、相对（P = 0.23）或经异速生长标度的FMD（P = 0.38）均无变化。男性和女性的静息和峰值舒张直径均未改变（所有P>0.05），且任何测量指标在时间和性别之间均无交互作用（P>0.05）。雌二醇在基线时与相对FMD不相关（r = -0.22，P = 0.42），从基线到运动后1小时相对FMD的变化也不相关（r = 0.24，P = 0.40）。总体而言，单次SIT后男性和女性的肱动脉FMD似乎未改变，女性较高的雌二醇浓度并未增强基线或运动后的FMD反应。3组×20秒的低运动量短跑间歇运动模式可能不足以改变健康男性和女性的肱动脉内皮功能。
