Zavorsky G S, Murias J M, Gow J, Kim D J, Poulin-Harnois C, Kubow S, Lands L C
Department of Anesthesia, McGill University, Montreal, Canada.
Int J Sports Med. 2007 Sep;28(9):743-8. doi: 10.1055/s-2007-964969. Epub 2007 Apr 23.
This study evaluated the reproducibility of laboratory based 20-km time trials in well trained versus recreational cyclists. Eighteen cyclists (age = 34 +/- 8 yrs; body mass index = 23.1 +/- 2.2 kg/m (2); VO(2max) = 4.19 +/- 0.65 L/min) completed three 20-km time trials over a month on a Velotron cycle ergometer. Average power output (PO) (W), speed, and heart rate (HR) were significantly lower in the first time trial compared to the second and third time trial. The coefficients of variation (CV) between the second and third trial of the top eight performers for average PO, time to completion, and speed were 1.2 %, 0.6 %, 0.5 %, respectively, compared to 4.8 %, 2.0 %, and 2.3 % for the bottom ten. In addition, the average HR, VO(2), and percentage of VO(2max) were similar between trials. This study demonstrated that (1) a familiarization session improves the reliability of the measurements (i.e., average PO, time to completion and speed), and (2) the CV was much smaller for the best performers.
本研究评估了训练有素的自行车运动员与业余自行车运动员基于实验室的20公里计时赛的可重复性。18名自行车运动员（年龄=34±8岁；体重指数=23.1±2.2kg/m²；最大摄氧量=4.19±0.65L/min）在一个月内于Velotron自行车测力计上完成了三次20公里计时赛。与第二次和第三次计时赛相比，第一次计时赛的平均功率输出（PO）（瓦特）、速度和心率（HR）显著更低。前八名运动员第二次和第三次计时赛之间平均PO、完成时间和速度的变异系数（CV）分别为1.2%、0.6%、0.5%，而后十名的变异系数分别为4.8%、2.0%和2.3%。此外，各次计时赛之间的平均心率、摄氧量和最大摄氧量百分比相似。本研究表明：（1）一次适应性训练可提高测量的可靠性（即平均PO、完成时间和速度）；（2）表现最佳者的CV要小得多。
