Human Performance Laboratory, School of Science and Health, University of Western Sydney, Sydney, Australia.
J Strength Cond Res. 2014 May;28(5):1226-34. doi: 10.1097/JSC.0000000000000226.
The premise of eliciting the greatest acute fatigue is accepted and used for designing programs that include excessive, potentially dangerous volumes of high-intensity resistance exercise. There is no evidence examining acute fatigue and neuromuscular responses throughout multiple sets of moderate-to-high intensity resistance exercise. Fifteen resistance-trained male subjects performed a single exercise session using 8 sets of Bulgarian split squats performed at 75% maximal force output. Maximal force output (N) was measured after every set of repetitions. Electromyographic (EMG) activity of vastus lateralis was monitored during all force trials and exercise repetitions. Repetitions per set decreased from the first to the third set (p < 0.001). Maximal force output decreased from preexercise to set 4 (p < 0.001). Electromyographic amplitudes during exercise did not change. Secondary subgroup analysis was performed based on the presence, or not, of a fatigue plateau (<5% reductions in maximal force output in subsequent sets). Nine participants exhibited a fatigue plateau, and 6 did not. Participants who plateaued performed less first-set repetitions, accrued less total volume, and did not exhibit increases in EMG amplitudes during exercise. Initial strength levels and neuromuscular demand of the exercise was the same between the subgroups. These data suggest that there are individual differences in the training session responses when prescribing based off a percentage of maximal strength. When plateaus in fatigue and repetitions per set are reached, subsequent sets are not likely to induce greater fatigue and muscle activation. High-volume resistance exercise should be carefully prescribed on an individual basis, with intrasession technique and training responsiveness continually monitored.
在设计包括过度、潜在危险的高负荷高强度抗阻运动的方案时，人们接受并使用了诱发最大急性疲劳这一前提。目前，还没有研究在多组中等到高强度抗阻运动中，对急性疲劳和神经肌肉反应进行检查。15 名有抗阻训练经验的男性受试者进行了一次单组运动，使用保加利亚分裂深蹲，强度为最大力量输出的 75%，共 8 组。每完成一组重复，都要测量最大力量输出（N）。在所有力量测试和运动重复过程中，监测股外侧肌的肌电图（EMG）活动。每组的重复次数从第一组到第三组逐渐减少（p < 0.001）。从运动前到第 4 组，最大力量输出减少（p < 0.001）。运动过程中 EMG 幅度没有变化。根据是否存在疲劳平台（后续组中最大力量输出减少<5%），进行了二次亚组分析。9 名参与者出现了疲劳平台，6 名没有。出现疲劳平台的参与者第一组重复次数较少，总容量较少，运动过程中 EMG 幅度没有增加。亚组之间的初始力量水平和运动的神经肌肉需求相同。这些数据表明，当根据最大力量的百分比进行处方时，训练过程中的个体反应存在差异。当疲劳和每组重复次数达到平台时，后续组不太可能引起更大的疲劳和肌肉激活。高负荷抗阻运动应根据个体情况谨慎规定，同时持续监测术中技术和训练反应性。
