Cafarelli E
Eur J Appl Physiol Occup Physiol. 1977 Oct 31;37(3):181-9. doi: 10.1007/BF00421773.
The relationships between some physical and physiological events, and perceived effort were studied at several equivalent work outputs (W) at two pedalling rates (30 and 60 rev-min-1). Subjects judged effort throughout a 4 min exercise bout. After 4 min at any W it was always more effortful to pedal at 30 rev-min-1 even though there were no differences in VE, VO2, or integrated electromyography per minute (IEMG-min-1) between pedalling rates. Effort was related to VO2 and IEMG-min-1 but it was more effortful to pedal at 30 rev-min-1. Effort was also related to pedal resistance and IEMG of single contractions but was influenced by pedalling rate after 4 min of exercise. At any resistance it was more effortful to pedal at 60 rev-min-1, however, when effort was plotted as a function of resistance after 15 s, there was virtually no effect of pedalling rate. The rate effect grows with time from the onset of exercise and appears to be related to the central signal to the effort sense. The interaction of peripheral and central signals suggests a model of the effort sense during exercise.
在两种蹬踏频率（30转/分钟和60转/分钟）下，于几个等效的工作输出（W）水平研究了一些身体和生理事件与主观用力感觉之间的关系。受试者在4分钟的运动期间判断用力程度。在任何工作输出水平下持续4分钟后，以30转/分钟的频率蹬踏总是感觉更费力，尽管不同蹬踏频率之间的每分钟通气量（VE）、摄氧量（VO2）或每分钟积分肌电图（IEMG-min-1）并无差异。用力感觉与VO2和IEMG-min-1相关，但以30转/分钟的频率蹬踏感觉更费力。用力感觉也与蹬踏阻力和单次收缩的肌电图相关，但在运动4分钟后受蹬踏频率影响。在任何阻力下，以60转/分钟的频率蹬踏感觉更费力，然而，当将15秒后的用力程度绘制成阻力的函数时，蹬踏频率几乎没有影响。频率效应从运动开始随着时间增加，并且似乎与传递至用力感觉的中枢信号有关。外周和中枢信号的相互作用提示了运动期间用力感觉的一种模型。
