Mausehund Lasse, Krosshaug Tron
Department of Physical Performance, Norwegian School of Sport Sciences, Oslo, Norway; and.
Department of Sports Medicine, Oslo Sports Trauma Research Center, Norwegian School of Sports Sciences, Oslo, Norway.
J Strength Cond Res. 2023 Jan 1;37(1):9-17. doi: 10.1519/JSC.0000000000004191. Epub 2021 Dec 23.
Mausehund, L and Krosshaug, T. Understanding bench press biomechanics-Training expertise and sex affect lifting technique and net joint moments. J Strength Cond Res 37(1): 9-17, 2023-The purpose of this study was to compare normalized net joint moments (NJMs), moment arms, and muscle activity in the bench press exercise between powerlifters and recreationally strength-trained lifters and between women and men. Thirty-four healthy adults, including 12 powerlifters (6 women and 6 men) and 22 recreational lifters (9 women and 13 men), performed a 6-8 repetition maximum set of the bench press, while elbow and shoulder NJMs and moment arms and electromyographic (EMG) activity of 6 upper extremity muscles were recorded. The results showed that training expertise and sex affected bench press technique substantially. Powerlifters applied a different bar path which impacted joint kinematics to a greater extent and joint kinetics to a lesser extent. Specifically, powerlifters had lower normalized peak elbow NJMs and shorter joint ROMs than recreational lifters ( p ≤ 0.05), yet no differences in normalized shoulder NJMs and muscle activity were observed. Women showed lower normalized mean shoulder NJMs, higher normalized peak elbow NJMs, and higher mean elbow to shoulder NJM ratios than men ( p ≤ 0.05). The muscle activity of the long head of the triceps brachii and the elbow to shoulder EMG ratio were higher, yet muscle activity of the sternocostal and abdominal head of the pectoralis major was lower for female than for male subjects ( p ≤ 0.05). In conclusion, powerlifters and men are more shoulder dominant when performing the bench press than recreational lifters and women, respectively. These findings will have implications for resistance training program design, expected training adaptations and bench press performance.
毛瑟洪德、L和克罗斯豪格、T。理解卧推生物力学——训练专业水平和性别影响举重技术和净关节力矩。《力量与体能研究杂志》37(1):9 - 17，2023年——本研究的目的是比较力量举运动员与休闲力量训练者以及女性与男性在卧推练习中的标准化净关节力矩（NJMs）、力臂和肌肉活动。34名健康成年人，包括12名力量举运动员（6名女性和6名男性）和22名休闲举重者（9名女性和13名男性），进行了一组6 - 8次最大重复次数的卧推，同时记录肘部和肩部的NJMs、力臂以及6块上肢肌肉的肌电图（EMG）活动。结果表明，训练专业水平和性别对卧推技术有显著影响。力量举运动员采用了不同的杠铃路径，对关节运动学的影响更大，对关节动力学的影响较小。具体而言，力量举运动员的标准化峰值肘部NJMs较低，关节活动范围（ROM）比休闲举重者短（p≤0.05），但标准化肩部NJMs和肌肉活动没有差异。女性的标准化平均肩部NJMs较低，标准化峰值肘部NJMs较高，肘部与肩部NJM比值高于男性（p≤0.05）。女性肱三头肌长头的肌肉活动以及肘部与肩部的EMG比值较高，但女性胸大肌胸骨肋部和腹部头部的肌肉活动低于男性受试者（p≤0.05）。总之，在进行卧推时，力量举运动员和男性分别比休闲举重者和女性更依赖肩部。这些发现将对阻力训练计划设计、预期的训练适应性和卧推表现产生影响。
