Currie Katharine D, Thomas Scott G, Goodman Jack M
Faculty of Physical Education and Health, University of Toronto, Toronto, ON, M5S 2W6, Canada.
Eur J Appl Physiol. 2009 Sep;107(2):211-8. doi: 10.1007/s00421-009-1116-4. Epub 2009 Jun 25.
We investigated effects of 6 days of endurance exercise training [cycling at 65% of peak oxygen consumption (VO(2peak)) for 2 h a day on six consecutive days] on vascular function in young males. Measures of VO(2peak), arterial stiffness, calf vascular conductance and heart rate variability were obtained pre- and post-training. Indices of arterial stiffness were obtained by applanation tonometry to determine aortic augmentation index normalized to a heart rate of 75 bpm (AI(x) at 75 bpm), and central and peripheral pulse wave velocity (CPWV, PPWV). Resting and maximal calf vascular conductances were calculated from concurrent measures of blood pressure and calf blood flow using venous occlusion strain-gauge plethysmography. Time and frequency domain measures of heart rate variability were obtained from recording R-R intervals during supine and standing conditions. Both CPWV (5.9 +/- 0.8 vs. 5.4 +/- 0.8 m/s) and PPWV (9.7 +/- 0.8 vs. 8.9 +/- 1.3 m/s) were reduced following the training program. No significant changes were observed in AI(x) at 75 bpm, vascular conductance, heart rate variability or VO(2peak). These data indicate that changes in arterial stiffness independent of changes in heart rate variability or vascular conductance can be achieved in healthy young males following only 6 days of intense endurance exercise.
我们研究了连续6天进行耐力运动训练[以峰值耗氧量（VO₂peak）的65%进行骑自行车运动，每天2小时，连续6天]对年轻男性血管功能的影响。在训练前后分别获取了VO₂peak、动脉僵硬度、小腿血管传导率和心率变异性的测量值。通过压平式眼压测量法获得动脉僵硬度指标，以确定标准化至心率75次/分钟时的主动脉增强指数（75次/分钟时的AI(x)）以及中心和外周脉搏波速度（CPWV、PPWV）。使用静脉阻塞应变片体积描记法，根据同时测量的血压和小腿血流量计算静息和最大小腿血管传导率。通过记录仰卧和站立状态下的R-R间期，获得心率变异性的时域和频域测量值。训练后，CPWV（5.9±0.8对5.4±0.8米/秒）和PPWV（9.7±0.8对8.9±1.3米/秒）均降低。75次/分钟时的AI(x)、血管传导率、心率变异性或VO₂peak未观察到显著变化。这些数据表明，仅经过6天的高强度耐力运动训练，健康年轻男性即可实现独立于心率变异性或血管传导率变化的动脉僵硬度改变。
