Capelli Carlo, Ardigo Luca Paolo, Schena Federico, Zamparo Paola
Department of Neurological and Visual Sciences, School of Exercise Sciences, University of Verona, Verona, Italy.
Ergonomics. 2008 Oct;51(10):1565-75. doi: 10.1080/00140130802238614.
When dealing with human-powered vehicles, it is important to quantify the capability of converting metabolic energy in useful mechanical work by measuring mechanical efficiency. In this study, net mechanical efficiency (eta) of riding a recumbent bicycle on flat terrain and at constant speeds (v, 5.1-10.0 m/s) was calculated dividing mechanical work (w, J/m) by the corresponding energy cost (C(c), J/m). w and C(c) increased linearly with the speed squared: w = 9.41 + 0.156 . v(2); C(c) = 39.40 + 0.563 . v(2). eta was equal to 0.257 +/- 0.0245, i.e. identical to that of concentric muscular contraction. Hence, i) eta seems unaffected by the biomechanical arrangement of the human-vehicle system; ii) the efficiency of transmission seems to be close to 100%, suggesting that the particular biomechanical arrangement does not impair the transformation of metabolic energy in mechanical work. When dealing with human-powered vehicles, it is important to quantify mechanical efficiency (eta) of locomotion. eta of riding a recumbent bicycle was calculated dividing the mechanical work to the corresponding energy cost of locomotion; it was practically identical to that of concentric muscular contraction (0.257 +/- 0.0245), suggesting that the power transmission from muscles to pedals is unaffected by the biomechanical arrangement of the vehicle.
在处理人力车辆时，通过测量机械效率来量化将代谢能量转化为有用机械功的能力非常重要。在本研究中，在平坦地形上以恒定速度（v，5.1 - 10.0 m/s）骑卧式自行车的净机械效率（η）通过将机械功（w，J/m）除以相应的能量消耗（C(c)，J/m）来计算。w和C(c)随速度平方呈线性增加：w = 9.41 + 0.156·v²；C(c) = 39.40 + 0.563·v²。η等于0.257 ± 0.0245，即与同心肌肉收缩的效率相同。因此，i）η似乎不受人车系统生物力学结构的影响；ii）传动效率似乎接近100%，这表明特定的生物力学结构不会损害代谢能量向机械功的转化。在处理人力车辆时，量化运动的机械效率（η）很重要。骑卧式自行车的η通过将机械功除以相应的运动能量消耗来计算；它实际上与同心肌肉收缩的效率（0.257 ± 0.0245）相同，这表明从肌肉到踏板的动力传输不受车辆生物力学结构的影响。
