Amann Markus, Subudhi Andrew, Foster Carl
The Orthopedic Specialty Hospital, Salt Lake City, UT 84121, USA.
Med Sci Sports Exerc. 2004 Apr;36(4):613-22. doi: 10.1249/01.mss.0000122076.21804.10.
To compare the ventilatory response of two incremental exercise tests and determine their predictive validity on 40-km cycle time trial (40K) mean power output (40Kavgwatts).
Fifteen male cyclists performed two incremental exercise tests (T50x3:100 W +50 W x 3(-1) min, T25x1:20 W + 25 W x min(-1)) and a 40K over an 8-d period. Key variable was power at ventilatory threshold (VT). For VT determination during each test we used: VE/VO2 method, first clear breakpoint on the VE/VCO2 plot, V-slope method, RER = 1, and RER = 0.95.
VO2max during T50x3 and T25x1 was not different (66.6 vs 67.6 mL x kg(-1) x min(-1)), although T25x1 peak power output (MaxT25x1; 402 W) was significantly higher than MaxT50x3 (363 W). T50x3 and T25x1 VT power outputs indicated that the power output at T25x1:RER = 1 and T25x1:RER = 0.95 were significantly higher compared with T50x3 (324 vs 304 W and 282 vs 264 W, respectively). Regression analyses between T50x3 variables and 40Kavgwatts were significant for T50x3:V-slope (R2 = 0.37; SEE 20.2 W), T50x3:VE/VO2 (R2 = 0.64; SEE 15.3 W), T50x3:RER = 0.95 (R2 = 0.42; SEE 19.4 W), T50x3:RER = 1 (R2 = 0.45; SEE 18.8 W), and MaxT50x3 (R2 = 0.51; SEE 17.8 W). Regression analyses between T25x1 variables and 40Kavgwatts were significant for T25x1:V-slope (R2 = 0.63; SEE 15.4 W), T25x1:VE/VO2 (R2 = 0.64; SEE 15.2 W), T25x1:RER = 0.95 (R2 = 0.53; SEE 17.4 W), T25x1:RER = 1 (R2 = 0.57; SEE 16.7 W), and MaxT25x1 (R2 = 0.65; SEE 15.0 W). There was no significant difference between 40Kavgwatts (282 W) and power outputs at T50x3:VE/VO2 (277 W), T50x3:V-slope (289 W), T25x1:VE/VO2 (276 W), and T25x1:RER = 0.95 (282 W).
Generally, T25x1 based VT variables were superior to T50x3 variables regarding the prediction of 40Kavgwatts. We conclude that the VE/VO2 method is protocol independent and a valid 40Kavgwatts predictor.
比较两种递增运动试验的通气反应，并确定它们对40公里自行车计时赛（40K）平均功率输出（40Kavgwatts）的预测效度。
15名男性自行车运动员在8天内进行了两项递增运动试验（T50x3：100瓦+50瓦×3（-1）分钟，T25x1：20瓦+25瓦×分钟（-1））和一次40K骑行。关键变量是通气阈（VT）时的功率。在每次试验中，我们使用以下方法确定VT：每分钟通气量/摄氧量（VE/VO2）法、VE/二氧化碳排出量（VE/VCO2）图上的第一个明显断点、V斜率法、呼吸商（RER）=1以及RER=0.95。
T50x3和T25x1期间的最大摄氧量（VO2max）无差异（66.6对67.6毫升×千克（-1）×分钟（-1）），尽管T25x1的峰值功率输出（MaxT25x1；402瓦）显著高于MaxT50x3（363瓦）。T50x3和T25x1的VT功率输出表明，与T50x3相比，T25x1：RER = 1和T25x1：RER = 0.95时的功率输出显著更高（分别为324对304瓦和282对264瓦）。T50x3变量与40Kavgwatts之间的回归分析对于T50x3：V斜率（R2 = 0.37；标准误20.2瓦）、T50x3：VE/VO2（R2 = 0.64；标准误15.3瓦）、T50x3：RER = 0.95（R2 = 0.42；标准误19.4瓦）、T50x3：RER = 1（R2 = 0.45；标准误18.8瓦）以及MaxT50x3（R2 = 0.51；标准误17.8瓦）均具有显著性。T25x1变量与40Kavgwatts之间的回归分析对于T25x1：V斜率（R2 = 0.63；标准误15.4瓦）、T25x1：VE/VO2（R2 = 0.64；标准误15.2瓦）、T25x1：RER = 0.95（R2 = 0.53；标准误17.4瓦）、T25x1：RER = 1（R2 = 0.57；标准误16.7瓦）以及MaxT25x1（R2 = 0.65；标准误15.0瓦）均具有显著性。40Kavgwatts（282瓦）与T50x3：VE/VO2（277瓦）、T50x3：V斜率（289瓦）以及T25x1：VE/VO2（276瓦）和T25x1：RER = 0.95（282瓦）时的功率输出之间无显著差异。
一般来说，基于T25x1的VT变量在预测40Kavgwatts方面优于T50x3变量。我们得出结论，VE/VO2方法与试验方案无关，是一种有效的40Kavgwatts预测指标。
