Mayo Clinic Program in Physical Therapy, Mayo Clinic College of Medicine, Rochester, Minnesota.
Physical Medicine and Rehabilitation, Mayo Clinic, Rochester, Minnesota.
Sports Health. 2018 Jul-Aug;10(4):355-360. doi: 10.1177/1941738118769845. Epub 2018 Apr 12.
External rotation (ER) strengthening of the shoulder is an integral component of rehabilitative and preventative programs for overhead athletes. A variety of shoulder ER strengthening exercises are reported, including those intended to integrate the core musculature. The purpose of this study was to examine ER torque and electromyographic (EMG) activation of shoulder and trunk muscles while performing resisted isometric shoulder ER in 3 positions (standing, side lying, and side plank).
Significantly greater force and shoulder muscle activation would be generated while side lying given the inherent stability of the position, and greater trunk muscle activation would be generated in the less stable plank position.
Quasi-experimental repeated-measures study.
Level 5.
A convenience sample of 25 healthy overhead recreational athletes (9 men, 16 women) participated in this study. EMG electrodes were placed on the infraspinatus, posterior deltoid, middle trapezius, multifidi, internal obliques, and external obliques. EMG signals were normalized to a maximal isometric contraction. Participants performed resisted isometric ER in standing, side-lying, and side plank positions. Results were analyzed using a repeated-measures analysis of variance with post hoc Bonferroni corrections (α = 0.05).
There was no significant difference in ER torque between positions (α = 0.05). A significant difference in EMG activity of shoulder and trunk musculature between positions was found in 7 of the 8 muscles monitored. Significantly greater EMG activity in the infraspinatus, middle trapezius, and the nondominant external and internal obliques was found in the side plank position as compared with standing and side lying.
While there was no difference in ER torque between the 3 exercise positions, EMG activity of the shoulder and trunk muscles was dependent on body position.
If a clinician is seeking to integrate trunk muscle activation while performing shoulder ER strengthening, the side plank position is preferred as compared with standing or side lying.
外旋（ER）强化是肩部康复和预防计划的一个重要组成部分，针对过头运动员。各种肩部 ER 强化练习都有报道，包括旨在整合核心肌肉的练习。本研究的目的是在 3 种体位（站立、侧卧和侧平板支撑）下进行抗等长肩部 ER 时，检查肩部和躯干肌肉的 ER 扭矩和肌电图（EMG）激活情况。
由于侧卧的固有稳定性，在侧卧时会产生更大的力和肩部肌肉激活，而在较不稳定的平板支撑位置会产生更大的躯干肌肉激活。
半实验性重复测量研究。
5 级。
本研究便利选取了 25 名健康的上肢娱乐运动员（9 名男性，16 名女性）参与。在冈下肌、后三角肌、中斜方肌、多裂肌、内斜肌和外斜肌上放置 EMG 电极。EMG 信号被归一化为最大等长收缩。参与者在站立、侧卧和侧平板支撑位置进行抗等长 ER。使用重复测量方差分析进行结果分析，并进行事后 Bonferroni 校正（α=0.05）。
在位置之间，ER 扭矩没有显著差异（α=0.05）。在监测的 8 块肌肉中的 7 块肌肉中，位置之间的肩部和躯干肌肉 EMG 活动存在显著差异。与站立和侧卧相比，在侧平板支撑位置，冈下肌、中斜方肌和非优势侧的内、外斜肌的 EMG 活动显著增加。
虽然在 3 种运动位置之间，ER 扭矩没有差异，但肩部和躯干肌肉的 EMG 活动依赖于身体位置。
如果临床医生在进行肩部 ER 强化时寻求整合躯干肌肉激活，那么与站立或侧卧相比，侧平板支撑位置是首选。
