Hedt Corbin, Lambert Bradley S, Daum Joshua, Pearson Jentry M, McCulloch Patrick C
Houston Methodist Orthopedics & Sports Medicine, Houston, TX, USA.
Willis-Knighton Orthopedics & Sports Medicine, Shreveport, LA, USA.
Int J Sports Phys Ther. 2020 Dec;15(6):1110-1118. doi: 10.26603/ijspt20201110.
Eccentric exercise has demonstrated great utility in the rehabilitation of various shoulder pathologies. Research on the electromyographic (EMG) activity of the shoulder musculature during these activities is limited, however. Furthermore, no studies have observed how forearm positioning during exercise affects EMG output.
PURPOSE/HYPOTHESIS: The purpose was to examine the degree of specific muscle recruitment among commonly used eccentric exercises in rehabilitation of the upper extremity and shoulder. Secondarily, the authors hypothesized that different hand/forearm positions would alter EMG activity within the targeted musculature during a given exercise.
Prospective cross-sectional observation of EMG analysis.
This study analyzed surface EMG data obtained from 10 healthy individuals during five eccentric exercises of the dominant extremity, performed in a randomized order: side-lying eccentric horizontal abduction (SL ER), half-kneeling weighted ball decelerations (BALL DC), seated eccentric external rotation in scaption (STD ER), standing eccentric external rotation at 0deg (STND ER), supine eccentric external rotation at 90deg (SUP ER). Each exercise was performed with two to three forearm position variants commonly used in clinical environments: neutral, pronation, and/or supination. EMG data were collected from the upper trapezius, infraspinatus, teres minor, latissimus dorsi, and anterior/middle/posterior deltoid. Data were analyzed for each individual exercise and within each muscle using a mixed-model ANOVA repeated across forearm position. Significant interactions were followed by a Bonferroni post-hoc test for pairwise comparisons. Effect size was calculated for all significant pairwise comparisons using a Cohen's d statistic.
Significant differences in EMG activity for the selected musculature exist between forearm positions for four of the five exercises and Cohen's d effect sizes 0.178 - 1.159.
Specific eccentric shoulder exercises activate muscles of the shoulder complex differently based on forearm positioning.
Level 2.
离心运动在各种肩部疾病的康复中已显示出巨大的效用。然而，关于这些活动期间肩部肌肉组织的肌电图（EMG）活动的研究有限。此外，尚无研究观察运动期间前臂位置如何影响肌电图输出。
目的/假设：目的是检查上肢和肩部康复中常用离心运动中特定肌肉募集的程度。其次，作者假设在给定运动期间，不同的手/前臂位置会改变目标肌肉组织内的肌电图活动。
肌电图分析的前瞻性横断面观察。
本研究分析了10名健康个体在优势肢体的五种离心运动中获得的表面肌电图数据，这些运动以随机顺序进行：侧卧离心水平外展（SL ER）、半跪加权球减速（BALL DC）、坐位离心外旋（STD ER）、站立位0度离心外旋（STND ER）、仰卧位90度离心外旋（SUP ER）。每项运动都采用临床环境中常用的两到三种前臂位置变体进行：中立位、旋前和/或旋后。从斜方肌上部、冈下肌、小圆肌、背阔肌以及三角肌前束/中束/后束收集肌电图数据。对每项运动以及每块肌肉内的数据进行分析，使用重复测量前臂位置的混合模型方差分析。显著的交互作用之后是用于两两比较的Bonferroni事后检验。使用Cohen's d统计量计算所有显著两两比较的效应大小。
在五种运动中的四种运动中，前臂位置之间所选肌肉组织的肌电图活动存在显著差异，Cohen's d效应大小为0.178 - 1.159。
特定的肩部离心运动根据前臂位置不同程度地激活肩部复合体的肌肉。
2级。
