de Mendonca Goncalo Vilhena, Margarida Correia Joana, Gomes Miguel, Dias Gonçalves André, Vila-Chã Carolina, Pezarat-Correia Pedro
Neuromuscular Research Lab, Faculdade de Motricidade Humana, Universidade de Lisboa, Cruz Quebrada, Dafundo, Portugal.
CIPER, Faculdade de Motricidade Humana, Universidade de Lisboa, Estrada da Costa, Cruz Quebrada, Dafundo, Portugal.
J Hum Kinet. 2022 Apr 26;82:27-37. doi: 10.2478/hukin-2022-0028. eCollection 2022 Apr.
Exploring acute neuromuscular fatigue induced by different modalities of resistance exercise would help understand the adaptation subsequent to specific training programs. Therefore, we investigated the acute impact of high-intensity and low-intensity blood flow-restricted resistance exercise on the development of explosive torque throughout the torque-time curve. Seventeen healthy, young participants were included in a randomized, counterbalanced within-subjects design study, in which participants underwent two experimental conditions, separated by a 1-wk period. Low-intensity blood-flow restricted exercise and high-intensity resistance exercise were performed using dynamic elbow flexion at 20 and 75% of 1 repetition maximum, respectively. Maximal voluntary contraction (MVC) and the sequential rate of torque development (absolute and relative) were measured before and after exercise. Both protocols elicited a similar decrement in MVC (~ 25%) and in the peak rate of torque development after exercise (~ 45%). The absolute rate of torque development (0-50 and 50-100 ms) was also reduced (p<0.05) similarly between conditions. After normalizing torque values to MVC, this was only sustained for the rate of torque development 0-50ms (p<0.05). We found that both exercise protocols induced similar acute attenuation of the absolute rate of torque development up to the first 100 ms of MVC. We also demonstrated that the reduction in the rate of torque development between 50-100ms (in both protocols) was largely explained by an acute deficit in muscle strength post-exercise. Conversely, the impact of each protocol on the first 50ms of muscle torque did not depend on lower levels of muscle strength after exercise.
探索不同形式的抗阻运动所诱发的急性神经肌肉疲劳，将有助于理解特定训练计划后的适应性变化。因此，我们研究了高强度和低强度血流限制抗阻运动对整个扭矩-时间曲线爆发力矩发展的急性影响。17名健康的年轻参与者被纳入一项随机、交叉的受试者内设计研究，其中参与者接受两种实验条件，间隔1周。低强度血流限制运动和高强度抗阻运动分别采用动态肘部屈曲进行，强度分别为1次重复最大值的20%和75%。在运动前后测量最大自主收缩（MVC）和扭矩发展的顺序速率（绝对值和相对值）。两种方案在运动后均引起MVC（约25%）和扭矩发展峰值速率（约45%）的类似下降。两种条件下，扭矩发展的绝对速率（0-50和50-100毫秒）也同样降低（p<0.05）。将扭矩值标准化为MVC后，这仅在扭矩发展速率0-50毫秒时持续存在（p<0.05）。我们发现，两种运动方案在MVC的前100毫秒内均引起扭矩发展绝对速率的类似急性衰减。我们还证明，50-100毫秒之间扭矩发展速率的降低（在两种方案中）很大程度上是由运动后肌肉力量的急性不足所解释。相反，每种方案对肌肉扭矩前50毫秒的影响并不取决于运动后较低的肌肉力量水平。
