Keerasomboon Taspol, Soga Toshiaki, Hirose Norikazu
College of Sports Science and Technology, Mahidol University, Thailand.
Graduate School of Sport Sciences, Waseda University, Japan.
Int J Sports Phys Ther. 2024 Mar 2;19(3):275-283. doi: 10.26603/001c.92745. eCollection 2024.
The benefit of performing the Nordic Hamstring Exercise (NHE) on an inclined board has been described, however, isometric hamstring activation in different knee and hip angles has not yet been thoroughly explored.
This study investigated the effect of variations in knee and hip angles during the isometric performance of the NHE on electromyographic activity of the hamstring muscles.
Crossover study.
Thirteen male volunteers performed isometric contractions during the NHE with the knee (30°, 50°, 60°) and the hip (0°, 30°, and 45°) in various angles of flexion on a leg support platform which was inclined at 30°. An electrical goniometer was used to monitor the knee and hip joint angles during 5-s isometric contractions. A multivariate analysis of variance with repeated measures was used to compare normalized electromyographic values of each muscle across different knee and hip angles, followed by pairwise comparisons.
The electromyographic activity of the biceps femoris, semitendinosus, and semimembranosus at a knee angle of 30° and hip angle of 0° were significantly higher than those observed with a knee angle of 50° and hip angle of 0°, or a knee angle of 60° and hip angle of 0° (p<0.05). The electromyographic activity of the semimembranosus at a knee angle of 60° and hip angle of 45° was significantly higher than values obtained with knee and hip angles of 60° and 0°, respectively (p<0.05).
The results indicate that using a knee flexion of 30° and a hip flexion of 0°, while isometrically performing the NHE on a platform inclined at 30°, may optimize electromyographic activity of the hamstrings.
已有研究描述了在斜板上进行北欧绳肌练习（NHE）的益处，然而，不同膝关节和髋关节角度下等长绳肌激活情况尚未得到充分研究。
本研究调查了NHE等长练习过程中膝关节和髋关节角度变化对绳肌肌电图活动的影响。
交叉研究。
13名男性志愿者在倾斜30°的腿部支撑平台上，于膝关节（30°、50°、60°）和髋关节（0°、30°和45°）的不同屈曲角度下进行NHE等长收缩。在5秒等长收缩过程中，使用电子测角仪监测膝关节和髋关节角度。采用重复测量的多因素方差分析比较不同膝关节和髋关节角度下各肌肉的标准化肌电图值，随后进行两两比较。
膝关节角度为30°且髋关节角度为0°时，股二头肌、半腱肌和半膜肌的肌电图活动显著高于膝关节角度为50°且髋关节角度为0°或膝关节角度为60°且髋关节角度为0°时的观察值（p<0.05）。膝关节角度为60°且髋关节角度为45°时，半膜肌的肌电图活动显著高于膝关节和髋关节角度分别为60°和0°时获得的值（p<0.05）。
结果表明，在倾斜30°的平台上进行NHE等长练习时，膝关节屈曲30°且髋关节屈曲0°可能会优化绳肌的肌电图活动。
3级。
