Ryschon T W, Stray-Gundersen J
Department of Internal Medicine, University of Texas, Southwestern Medical School, Dallas.
Ergonomics. 1993 Jun;36(6):661-6. doi: 10.1080/00140139308967927.
Cycling requires power generation to overcome gravity, air resistance, and rolling resistance. When rolling surface and rolling speed are constant for a given tyre, rolling resistance is determined by tyre inflation pressure and the combined weight (CW) of the bicycle and rider. In this study, the oxygen uptake per unit CW (VO2 x CW-1) of seven trained bicycle racers (5 men, 2 women, 24 +/- 2 years) was measured while each cycled up a 4% incline at 19.3 km.h-1 and 75 revolutions.min-1 on a motor-driven treadmill, using randomly-ordered tyre pressures of 552, 690, 827, and 965 kPa. Subjects (55.8-78.4 kg) rode their racing bicycles equipped with the same set of sew-up tyres and wheels. VO2.CW-1 was averaged over the last 3 min of a 5 min ride at each pressure. A repeated measures analysis of variance was performed and significance set at p < 0.05. VO2.CW-1 ranged from 28.1 +/- 0.6 to 28.9 +/- 0.5 ml.kg-1 x min-1 and was not significantly different between tyre pressures. We conclude that differences in rolling resistance caused by varying tyre pressure between 552 and 965 kPa, are too small to be detected physiologically.
骑行需要产生动力来克服重力、空气阻力和滚动阻力。对于给定的轮胎，当滚动表面和滚动速度恒定时，滚动阻力由轮胎充气压力以及自行车和骑行者的总重量（CW）决定。在本研究中，对7名训练有素的自行车赛车手（5名男性，2名女性，24±2岁）进行了测量，他们在电动跑步机上以19.3 km/h的速度和75转/分钟的转速沿4%的坡度骑行时，使用随机排列的552、690、827和965 kPa的轮胎压力，测量其每单位CW的摄氧量（VO2×CW-1）。受试者（体重55.8 - 78.4 kg）骑着配备相同一组缝式轮胎和车轮的赛车。在每个压力下，VO2.CW-1在5分钟骑行的最后3分钟内进行平均。进行了重复测量方差分析，显著性设定为p < 0.05。VO2.CW-1范围为28.1±0.6至28.9±0.5 ml.kg-1×min-1，不同轮胎压力之间无显著差异。我们得出结论，552至965 kPa之间轮胎压力变化所导致的滚动阻力差异过小，无法通过生理检测来察觉。
