Hollander Daniel B, Worley Jennifer R, Asoodeh Mike, Wakesa David, Magnuson Matthew, Dantzler Demetra K, Didier Jennifer J, Kraemer Robert R
1Department of Kinesiology and Health Studies, Southeastern Louisiana University, Hammond, Louisiana; 2Department of Computer Science and Industrial Technology, Southeastern Louisiana University, Hammond, Louisiana; and 3Department of Health and Kinesiology, Sam Houston State University, Huntsville, Texas.
J Strength Cond Res. 2017 May;31(5):1387-1394. doi: 10.1519/JSC.0000000000001290.
Hollander, DB, Worley, JR, Asoodeh, M, Wakesa, D, Magnuson, M, Dantzler, DK, Didier, JJ, and Kraemer, RR. Comparison of resistance exercise perceived exertion and muscle activation at varied submaximal durations, loads, and muscle actions. J Strength Cond Res 31(5): 1387-1394, 2017-Previous studies investigating muscle activation from dynamic, plate-loaded, concentric (CON) and eccentric (ECC) muscle contractions have not accounted for the greater absolute strength of ECC contractions. The purpose of the study was to determine the effect of different dynamic muscle contraction durations, loads, and contraction types (CON and ECC) on perceived exertion and muscle activation differences in 6 women (mean ± SD age, height, weight, body mass index 22.83 ± 2.56 years, 1.65 ± 0.261 m, 68.56 ± 2.72 kg, 25.26 ± 4.39 kg·m). The participants were recruited and trained to move weight at the appropriate duration (2, 3, 4, and 5 seconds) for leg extension using a displacement apparatus (sonic emitter, auditory) and a computer program (visual feedback of bar displacement). Concentric and ECC 1 repetition maximum (1RM) were determined for leg extension for the midrange 3-second duration. Thirty, 50, and 70% of either CON or ECC 1RM were loaded for the remainder of the sessions. Subjects were then assigned to complete trials in a counterbalanced fashion for load, contraction type, and contraction duration. Rating of perceived exertion (RPE) significantly increased in response to load (30, 50, and 70%) regardless of contraction type as did electromyography (EMG) root mean square amplitude. Greater time under tension significantly increased RPE regardless of contraction type during knee extension exercise. The EMG amplitude was less distinguishable between 2, 3, 4, and 5 seconds of contractions. The data highlight the effort sense distinctions made by women at submaximal exercise loads during knee extension. These findings should be used to develop effective resistance exercise protocols that facilitate positive perceptions and adherence resistance exercise loads, durations of contraction, and contraction type.
霍兰德，DB，沃利，JR，阿索德，M，瓦克萨，D，马格努森，M，丹茨勒，DK，迪迪埃，JJ，以及克雷默，RR。不同次最大持续时间、负荷和肌肉动作下抗阻运动主观用力感觉与肌肉激活的比较。《力量与体能研究杂志》31(5): 1387 - 1394，2017年 - 以往研究在探究动态、平板加载、向心（CON）和离心（ECC）肌肉收缩所产生的肌肉激活时，未考虑到离心收缩具有更大的绝对力量。本研究的目的是确定不同的动态肌肉收缩持续时间、负荷和收缩类型（CON和ECC）对6名女性（平均±标准差年龄、身高、体重、体重指数22.83±2.56岁，1.65±0.261米，68.56±2.72千克，25.26±4.39千克·米²）主观用力感觉和肌肉激活差异的影响。招募参与者并对其进行训练，使其使用位移装置（声波发射器、听觉）和计算机程序（杠铃位移的视觉反馈），以适当的持续时间（2、3、4和5秒）进行腿部伸展动作来移动重量。测定腿部伸展动作在3秒中等范围持续时间下的向心和离心1次重复最大值（1RM）。在其余的训练中，加载CON或ECC 1RM的30%、50%和70%。然后让受试者以平衡的方式完成关于负荷、收缩类型和收缩持续时间的试验。无论收缩类型如何，主观用力感觉评分（RPE）随着负荷（30%、50%和70%）的增加而显著升高，肌电图（EMG）均方根振幅也是如此。在膝关节伸展运动中，无论收缩类型如何，更大的张力作用时间均显著增加RPE。在2、3、4和5秒的收缩过程中，EMG振幅较难区分。这些数据突出了女性在膝关节伸展次最大运动负荷下的用力感觉差异。这些发现应用于制定有效的抗阻运动方案，以促进对积极的抗阻运动负荷、收缩持续时间和收缩类型的认知及坚持。
