Tsoukos Athanasios, Wilk Michal, Krzysztofik Michał, Zajac Adam, Bogdanis Gregory C
School of Physical Education and Sports Science, National & Kapodistrian University of Athens, Athens, Greece.
Institute of Sport Sciences, Jerzy Kukuczka Academy of Physical Education in Katowice, Katowice, Poland.
J Hum Kinet. 2024 Apr 15;91(Spec Issue):189-204. doi: 10.5114/jhk/186341. eCollection 2024 Mar.
This study examined the effects of range of motion (ROM) on applied force, power output and surface electromyographic (sEMG) responses during repeated sets of bench press exercise executed as fast as possible. Ten resistance trained men performed three sets to momentary failure with two-min rest intervals under three different ROM conditions: (a) full ROM (FULL), (b) TOP, at the top half of ROM, and (c) BOTTOM, at the bottom half of ROM. Mean and peak force were higher in TOP compared to FULL and BOTTOM (mean force: 817 ± 80 vs. 657 ± 98 vs. 623 ± 122 N, respectively, p < 0.001) with no differences between FULL and BOTTOM. During repeated sets, large decreases were found in peak (by 29.4 to 45.3%) and mean power (by 55.5 to 64.7%) from the first to the last repetitions. However, the decrease in mean force was only 2% (p < 0.01) and decreases in peak force ranged from 6.7 and 8.8% to zero, indicating the velocity loss was the main contributor to fatigue in power output. Although force and power output in set 3 were unchanged in BOTTOM, mean power output decreased significantly, suggesting that lower performance and fatigue may be related to the longer muscle length. Fatigue was accompanied by an increase in sEMG activity and a decrease in median frequency in all muscles, with triceps brachialis sEMG reflecting more the force and power differences among ROMs. In conclusion, fatigue depends on velocity rather than force loss during bench press exercise at different ROMs.
本研究考察了在尽可能快地进行重复几组卧推练习期间，运动范围（ROM）对施加力、功率输出和表面肌电图（sEMG）反应的影响。十名经过抗阻训练的男性在三种不同的ROM条件下进行三组练习至瞬间疲劳，每组练习间休息两分钟：（a）全ROM（FULL），（b）TOP，即ROM的上半部分，以及（c）BOTTOM，即ROM的下半部分。与FULL和BOTTOM相比，TOP的平均力和峰值力更高（平均力分别为：817±80 N、657±98 N、623±122 N，p<0.001），FULL和BOTTOM之间无差异。在重复几组练习期间，从第一次重复到最后一次重复，峰值（下降29.4%至45.3%）和平均功率（下降55.5%至64.7%）大幅下降。然而，平均力仅下降2%（p<0.01），峰值力下降幅度为6.7%至8.8%至零，表明速度损失是功率输出疲劳的主要原因。尽管在BOTTOM条件下第三组的力和功率输出未改变，但平均功率输出显著下降，表明较低的表现和疲劳可能与较长的肌肉长度有关。疲劳伴随着所有肌肉sEMG活动增加和中位频率降低，肱三头肌sEMG更能反映不同ROM之间的力和功率差异。总之，在不同ROM的卧推练习中，疲劳取决于速度而非力的损失。
