Huber A, Suter E, Herzog W
Faculty of Kinesiology, The University of Calgary, Alberta, Canada.
J Sports Sci. 1998 Apr;16(3):281-9. doi: 10.1080/026404198366812.
Inhibition of the quadriceps muscles was assessed in 13 elite male volleyball players using the interpolated twitch technique. This technique involves applying an electrical stimulus to the voluntarily contracted quadriceps muscles to estimate the number of motor units not fully activated during the contraction. Knee extensor moments and muscle inhibition were measured during isometric contractions at knee angles of 30 degrees and 60 degrees from full extension. A medical history of knee joint injury and pain experienced in the knee during testing were assessed. Previous knee joint injury did not affect the knee extensor moments, but produced a difference in muscle inhibition: muscle inhibition in legs with previous injuries was significantly lower than muscle inhibition in legs with no previous injury. Moderate pain in the knee during testing did not affect muscle inhibition, but was associated with reduced knee extensor moments. We consider that the loss in knee extensor moments associated with pain might be caused by atrophy of the quadriceps muscles as a consequence of the disrupted training routine. The lower muscle inhibition in volleyball players with previous injury suggested that the intense rehabilitation programme that these athletes undergo after knee injury improves muscle activation. As a result, athletes with previous knee joint injuries were able to produce the same knee extensor moments as athletes with no previous injury, probably because of their ability to recruit the available motor units more completely. This recruitment may compensate for the possible loss in muscle mass encountered during the period of injury and detraining.
采用内插式单刺激技术对13名男性排球精英运动员的股四头肌抑制情况进行了评估。该技术通过对主动收缩的股四头肌施加电刺激，来估计收缩过程中未完全激活的运动单位数量。在膝关节从完全伸展角度分别为30度和60度的等长收缩过程中，测量膝关节伸肌力矩和肌肉抑制情况。评估了膝关节损伤病史以及测试过程中膝关节所经历的疼痛情况。既往膝关节损伤并未影响膝关节伸肌力矩，但在肌肉抑制方面产生了差异：既往有损伤的腿部肌肉抑制明显低于无既往损伤的腿部。测试过程中膝关节的中度疼痛并未影响肌肉抑制，但与膝关节伸肌力矩降低有关。我们认为，与疼痛相关的膝关节伸肌力矩下降可能是由于训练常规被打乱导致股四头肌萎缩所致。既往有损伤的排球运动员肌肉抑制较低，这表明这些运动员在膝关节损伤后所接受的强化康复计划改善了肌肉激活情况。因此，既往有膝关节损伤的运动员能够产生与无既往损伤的运动员相同的膝关节伸肌力矩，这可能是因为他们能够更充分地募集可用的运动单位。这种募集可能弥补了损伤和停训期间可能出现的肌肉量损失。
