Ettema Gertjan, Lorås Håvard Wuttudal
Human Movement Science Programme, Faculty of Social Sciences and Technology Management, Norwegian University of Science and Technology, Trondheim, Norway.
Eur J Appl Physiol. 2009 May;106(1):1-14. doi: 10.1007/s00421-009-1008-7. Epub 2009 Feb 20.
We focus on the effect of cadence and work rate on energy expenditure and efficiency in cycling, and present arguments to support the contention that gross efficiency can be considered to be the most relevant expression of efficiency. A linear relationship between work rate and energy expenditure appears to be a rather consistent outcome among the various studies considered in this review, irrespective of subject performance level. This relationship is an example of the Fenn effect, described more than 80 years ago for muscle contraction. About 91% of all variance in energy expenditure can be explained by work rate, with only about 10% being explained by cadence. Gross efficiency is strongly dependent on work rate, mainly because of the diminishing effect of the (zero work-rate) base-line energy expenditure with increasing work rate. The finding that elite athletes have a higher gross efficiency than lower-level performers may largely be explained by this phenomenon. However, no firm conclusions can be drawn about the energetically optimal cadence for cycling because of the multiple factors associated with cadence that affect energy expenditure.
我们关注踏频和功率对骑行中能量消耗及效率的影响，并提出论据支持以下观点：总效率可被视为效率的最相关表达方式。在本综述所考虑的各项研究中，无论受试者的表现水平如何，功率与能量消耗之间的线性关系似乎是一个相当一致的结果。这种关系是芬恩效应的一个例子，该效应在80多年前就已针对肌肉收缩进行了描述。能量消耗中约91%的变异可由功率解释，而仅有约10%由踏频解释。总效率强烈依赖于功率，主要是因为（零功率）基线能量消耗随功率增加而产生的递减效应。精英运动员比低水平运动员具有更高总效率这一发现，很大程度上可由此现象解释。然而，由于与踏频相关的多种影响能量消耗的因素，无法就骑行的能量最优踏频得出确凿结论。
