Franke W D, Betz C B, Humphrey R H
Laboratory for Exercise, Sport and Work Physiology, Virginia Polytechnic Institute, Blacksburg.
Br J Sports Med. 1994 Mar;28(1):38-42. doi: 10.1136/bjsm.28.1.38.
Using 10 well-trained (VO2peak = 60.6 ml kg-1min-1) college age cyclists and continuous wave Doppler echocardiography, peak acceleration (PkA) and velocity (PkV) of blood flow in the ascending aorta, and the stroke velocity integral (SVI) were assessed to determine if rider position influenced the central haemodynamic responses to graded maximal cycle ergometry. Cyclist position was determined by hand placement on the uprights (UPRI) or drops (DROP) of conventional handlebars or using aerodynamic handlebars (AHB). All subjects consistently achieved a peak workload of 300 W. The Doppler variables did not differ significantly between rider positions at each stage of the maximal exercise tests but did change in response to increasing workloads. PkA was significantly (P < 0.05) greater at workloads > or = 240 W versus < or = 120 W. PkV increased significantly (P < 0.05) up to 180 W and then reached a plateau. SVI increased to a workload of 120 W and then progressively declined, becoming significantly (P < 0.05) less at 300 W. For each stage, neither submaximal VO2, VI nor heart rate (HR) differed significantly between each trial. These results suggest that rider position does not affect the physiological response to maximal bicycle ergometry as responses to each position are similar.
使用10名训练有素（峰值摄氧量=60.6毫升·千克⁻¹·分钟⁻¹）的大学生年龄的自行车运动员以及连续波多普勒超声心动图，评估升主动脉血流的峰值加速度（PkA）和速度（PkV）以及每搏输出速度积分（SVI），以确定骑行姿势是否会影响对分级最大运动负荷试验的中心血流动力学反应。骑行姿势通过手放在传统车把的直立部分（UPRI）或弯把部分（DROP）来确定，或者使用空气动力学车把（AHB）。所有受试者均持续达到300瓦的峰值工作量。在最大运动试验的每个阶段，多普勒变量在不同骑行姿势之间没有显著差异，但会随着工作量增加而变化。与≤120瓦相比，在工作量≥240瓦时，PkA显著更大（P<0.05）。PkV在达到180瓦之前显著增加（P<0.05），然后达到平稳状态。SVI增加到120瓦的工作量，然后逐渐下降，在300瓦时显著更小（P<0.05）。对于每个阶段，各次试验之间的次最大摄氧量、每搏输出量和心率（HR）均无显著差异。这些结果表明，骑行姿势不会影响对最大自行车运动负荷试验的生理反应，因为对每个姿势的反应相似。
