J Sport Rehabil. 2019 Sep 24;29(6):813-819. doi: 10.1123/jsr.2019-0118. Print 2020 Aug 1.
Within each hamstring muscle, there are segments with separate nerve innervation. However, a better understanding of activation levels within these regions during resistance exercise could lead to region-specific training for improved performance and injury prevention.
To compare muscle activation levels within regions of the hamstrings during various resistance exercises.
Within-subjects repeated measures.
Biomechanics laboratory.
Eighteen young adult females with previous competitive sport participation and resistance training experience.
One set of 3 repetitions with an 8RM load on the bilateral squat, modified single-leg squat, stiff-legged dead lift, and leg curl (LC).
Normalized surface electromyography of 4 hamstring regions (proximal-medial, proximal-lateral, distal-medial, and distal-lateral).
For LC only, electromyography measures for the proximal-lateral location were significantly lower than for the distal-lateral, t18 = 5.6, P < .001, and proximal-medial, t18 = 2.4, P = .01 locations for concentric contractions. Similar results were observed for eccentric contractions. No other exercises revealed regional activation differences. When comparing the pooled proximal (medial and lateral) region across exercises, the LC demonstrated significantly greater activation than the modified single-leg squat, t18 = 5.20, P < .001, stiff-legged dead lift, t18 = 7.311, P < .001, and bilateral squat, F3,54 = 49.8, P < .001. Similar significantly greater levels were also found during the LC for the pooled distal, medial, and lateral regions. In addition, the modified single-leg squat electromyography was significantly greater at all regions in comparison with the stiff-legged dead lift and bilateral squat.
The data did not reveal consistent regional differences within the different exercises included in this study. However, the data indicate that the LC produces the highest hamstring activation in all regions across exercises. Inclusion of single-joint knee-flexion exercises would appear to be most beneficial for hamstrings development in a resistance-training program.
在每条腘绳肌内，都有神经单独支配的肌节。然而，对这些区域在抗阻运动中激活水平的更好理解可能会导致针对特定区域的训练，从而提高运动表现和预防损伤。
比较不同抗阻运动中腘绳肌各区域的肌肉激活水平。
受试者内重复测量设计。
生物力学实验室。
18 名有过竞技运动经历和抗阻训练经验的年轻成年女性。
双侧深蹲、改良单腿深蹲、硬拉和腿弯举（LC）各 3 组，每组 3 次，采用 8RM 负荷。
4 个腘绳肌区域（近中、近侧外、远中内和远外侧）的表面肌电图归一化值。
仅在 LC 中，近外侧位置的肌电图测量值在向心收缩时明显低于远外侧，t18 = 5.6，P <.001，以及近内侧，t18 = 2.4，P =.01。在离心收缩时也观察到类似的结果。其他运动没有显示出区域激活差异。当比较跨运动的近端（内侧和外侧）区域时，LC 在向心收缩时的激活明显高于改良单腿深蹲，t18 = 5.20，P <.001，硬拉，t18 = 7.311，P <.001，以及双侧深蹲，F3,54 = 49.8，P <.001。在 LC 中，在向心收缩时，近端、远中、远内侧和远外侧的区域也发现了类似的明显更大的激活水平。此外，与硬拉和双侧深蹲相比，改良单腿深蹲的肌电图在所有区域都明显更大。
本研究中包含的不同运动并没有显示出一致的区域差异。然而，数据表明，LC 在所有运动中都能产生最高的腘绳肌激活。在抗阻训练计划中加入单关节膝关节屈伸运动似乎对腘绳肌的发展最有益。
