van den Tillaar Roland, Kwan Kedric
Department of Sport Sciences and Physical Education, Nord University, 7600 Levanger, Norway.
Sports Performance Research Institute New Zealand (SPRINZ), Auckland University of Technology, 0632 Auckland, New Zealand.
J Funct Morphol Kinesiol. 2020 Jan 26;5(1):8. doi: 10.3390/jfmk5010008.
The aim of this study was to investigate the effects of an augmented eccentric load upon the kinematics and muscle activation of bench press, and to investigate possible mechanisms behind augmented eccentric loading during the lift. Sixteen resistance-trained males (age 28.5 ± 7.7 years, height 1.78 ± 0.08 m, body mass 80.7 ± 14.3 kg) performed three repetitions at 95/85% of 1RM (augmented eccentric loading), and 85/85% of 1RM (control) in bench press, while barbell kinematics and muscle activation of eight muscles were measured. The main findings were that no kinematic differences between the augmented and control condition were found, only an effect of repetition. Furthermore, augmented loading caused a higher activation of the biceps brachii during the pre-sticking and sticking region, while a lower activation in the sternal part of pectoralis major during the eccentric phase was observed. Based on the present findings, it can be concluded that augmented eccentric loading with 95% of 1RM in bench press did not have any acute positive effect upon the concentric phase of the lift (85% of 1RM) and that the proposed underlying mechanisms like potentiation, increased neural stimulation and preload, and recovery of stored elastic energy does not seem to occur with these loads.
本研究的目的是调查增强离心负荷对卧推运动学和肌肉激活的影响,并探究在举重过程中增强离心负荷背后的可能机制。16名有阻力训练经验的男性(年龄28.5±7.7岁,身高1.78±0.08米,体重80.7±14.3千克)在卧推时以1RM的95/85%(增强离心负荷)和1RM的85/85%(对照组)进行三次重复动作,同时测量杠铃运动学和八块肌肉的肌肉激活情况。主要发现是,增强组和对照组之间未发现运动学差异,只有重复次数的影响。此外,增强负荷在预停滞和停滞阶段导致肱二头肌激活程度更高,而在离心阶段观察到胸大肌胸骨部分的激活程度较低。基于目前的研究结果,可以得出结论,卧推时以1RM的95%进行增强离心负荷对举重的向心阶段(1RM的85%)没有任何急性积极影响,并且所提出的诸如增强作用、增加神经刺激和预负荷以及储存弹性能量的恢复等潜在机制在这些负荷下似乎并未发生。