Ferguson R A, Aagaard P, Ball D, Sargeant A J, Bangsbo J
Neuromuscular Biology Group, Department of Exercise and Sport Science, Manchester Metropolitan University, Alsager ST7 2HL, United Kingdom.
J Appl Physiol (1985). 2000 Nov;89(5):1912-8. doi: 10.1152/jappl.2000.89.5.1912.
A novel approach has been developed for the quantification of total mechanical power output produced by an isolated, well-defined muscle group during dynamic exercise in humans at different contraction frequencies. The calculation of total power output comprises the external power delivered to the ergometer (i.e., the external power output setting of the ergometer) and the "internal" power generated to overcome inertial and gravitational forces related to movement of the lower limb. Total power output was determined at contraction frequencies of 60 and 100 rpm. At 60 rpm, the internal power was 18+/- 1 W (range: 16-19 W) at external power outputs that ranged between 0 and 50 W. This was less (P<0.05) than the internal power of 33+/-2 W (27-38 W) at 100 rpm at 0-50 W. Moreover, at 100 rpm, internal power was lower (P<0.05) at the higher external power outputs. Pulmonary oxygen uptake was observed to be greater (P<0.05) at 100 than at 60 rpm at comparable total power outputs, suggesting that mechanical efficiency is lower at 100 rpm. Thus a method was developed that allowed accurate determination of the total power output during exercise generated by an isolated muscle group at different contraction frequencies.
已开发出一种新方法，用于量化人体中一个孤立的、明确界定的肌肉群在不同收缩频率下进行动态运动时产生的总机械功率输出。总功率输出的计算包括传递到测力计的外部功率（即测力计的外部功率输出设置）以及为克服与下肢运动相关的惯性和重力而产生的“内部”功率。在60和100转/分钟的收缩频率下测定总功率输出。在60转/分钟时，外部功率输出在0至50瓦之间时，内部功率为18±1瓦（范围：16 - 19瓦）。这比100转/分钟、外部功率输出在0至50瓦时的内部功率33±2瓦（27 - 38瓦）要低（P<0.05）。此外，在100转/分钟时，较高外部功率输出下的内部功率更低（P<0.05）。在可比的总功率输出下，观察到100转/分钟时的肺摄氧量比60转/分钟时更大（P<0.05），这表明100转/分钟时的机械效率更低。因此，开发了一种方法，能够准确测定孤立肌肉群在不同收缩频率下运动期间的总功率输出。
