Discipline of Biomedical Science, Faculty of Medicine & Health, The University of Sydney, AUSTRALIA.
Discipline of Exercise & Sports Science, Faculty of Health Sciences, The University of Sydney, AUSTRALIA.
Med Sci Sports Exerc. 2020 Mar;52(3):680-684. doi: 10.1249/MSS.0000000000002177.
It is commonly believed that the shoulder external rotation (ER) to internal rotation (IR) strength ratio is decreased in swimmers due to predominant IR loading during the pull-through (propulsive) phase which predisposes to shoulder pain. However, the evidence supporting this hypothesis is inconclusive. Therefore, the aim of this study was to examine shoulder rotation strength parameters in elite swimmers and investigate potential associations with shoulder pain.
Sixty-eight (40 men; age, 19.9 ± 3.2 yr) elite swimmers provided demographic and shoulder pain history data before measurement of shoulder rotation strength. Mixed model analyses were used to examine differences in shoulder IR and ER strength normalized to body weight (BW) and the shoulder rotation strength ratio. A multinomial logistic regression model was utilized to examine associations between shoulder rotation strength parameters and shoulder pain.
Mean shoulder IR strength (BW) was approximately 0.29 for male swimmers and 0.26 for female swimmers. Mean shoulder ER strength (BW) was approximately 0.19 for male swimmers and 0.18 for female swimmer. The shoulder ER/IR strength ratio was approximately 0.70 bilaterally for all swimmers. There were no significant differences between dominant and nondominant shoulders in IR or ER strength normalized to BW (P ≥ 0.547). There were no associations between any shoulder strength parameters and shoulder pain (r = 0.032, P = 0.107).
Despite the high IR loading, optimal swimming technique does not alter the normal ER/IR strength ratio at the shoulder. Elite swimmers who report current or a history of shoulder pain demonstrate normal shoulder rotation strength ratios. The finding of symmetrical shoulder rotation strength points to side-to-side strength comparisons as a valuable clinical tool in managing swimmers with unilateral shoulder pain.
人们普遍认为，游泳运动员的肩部外旋（ER）与内旋（IR）力量比会降低，这是因为在推进阶段（推进阶段）IR 负荷占主导地位，容易导致肩部疼痛。然而，支持这一假设的证据并不明确。因此，本研究旨在检查优秀游泳运动员的肩部旋转力量参数，并调查与肩部疼痛的潜在关联。
68 名（40 名男性；年龄，19.9±3.2 岁）优秀游泳运动员在测量肩部旋转力量之前提供了人口统计学和肩部疼痛史数据。混合模型分析用于检查肩部 IR 和 ER 力量与体重（BW）标准化的差异，以及肩部旋转力量比。使用多项逻辑回归模型检查肩部旋转力量参数与肩部疼痛之间的关联。
男性游泳运动员的平均肩部 IR 力量（BW）约为 0.29，女性游泳运动员的平均肩部 ER 力量（BW）约为 0.26。所有游泳运动员的肩部 ER/IR 力量比约为 0.70。在 IR 或 ER 力量与 BW 标准化方面，优势肩和非优势肩之间没有显著差异（P≥0.547）。任何肩部力量参数与肩部疼痛之间均无关联（r=0.032，P=0.107）。
尽管存在高 IR 负荷，但最佳游泳技术不会改变肩部正常的 ER/IR 力量比。报告当前或有肩部疼痛史的优秀游泳运动员表现出正常的肩部旋转力量比。肩部旋转力量对称的发现表明，左右力量比较是管理单侧肩部疼痛游泳运动员的有价值的临床工具。
