Niederbracht Yvonne, Shim Andrew L, Sloniger Mark A, Paternostro-Bayles Madeline, Short Thomas H
Department of Health and Physical Education, Indiana University of Pennsylvania, Indiana, Pennsylvania, USA.
J Strength Cond Res. 2008 Jan;22(1):140-5. doi: 10.1519/JSC.0b013e31815f5634.
Imbalance of the eccentrically-activated external rotator cuff muscles versus the concentrically-activated internal rotator cuff muscles is a primary risk factor for glenohumeral joint injuries in overhead activity athletes. Nonisokinetic dynamometer based strength training studies, however, have focused exclusively on resulting concentric instead of applicable eccentric strength gains of the external rotator cuff muscles. Furthermore, previous strength training studies did not result in a reduction in glenoumeral joint muscle imbalance, thereby suggesting that currently used shoulder strength training programs do not effectively reduce the risk of shoulder injury to the overhead activity athlete. Two collegiate women tennis teams, consisting of 12 women, participated in this study throughout their preseason training. One team (n = 6) participated in a 5-week, 4 times a week, external shoulder rotator muscle strength training program next to their preseason tennis training. The other team (n = 6) participated in a comparable preseason tennis training program, but did not conduct any upper body strength training. Effects of this strength training program were evaluated by comparing pre- and posttraining data of 5 maximal eccentric external immediately followed by concentric internal contractions on a Kin-Com isokinetic dynamometer (Chattecx Corp., Hixson, Tennessee). Overall, the shoulder strength training program significantly increased eccentric external total work without significant effects on concentric internal total work, concentric internal mean peak force, or eccentric external mean peak force. In conclusion, by increasing the eccentric external total exercise capacity without a subsequent increase in the concentric internal total exercise capacity, this strength training program potentially decreases shoulder rotator muscle imbalances and the risk for shoulder injuries to overhead activity athletes.
在从事过头运动的运动员中，离心激活的肩袖外旋肌与向心激活的肩袖内旋肌之间的失衡是导致盂肱关节损伤的主要风险因素。然而，基于非等速测力计的力量训练研究仅关注肩袖外旋肌向心力量的提升，而非适用的离心力量增长。此外，先前的力量训练研究并未减少盂肱关节肌肉失衡，这表明目前使用的肩部力量训练计划并不能有效降低从事过头运动的运动员肩部受伤的风险。两个大学女子网球队，共12名队员，在季前训练期间参与了本研究。其中一个队（n = 6）在进行季前网球训练的同时，参加了为期5周、每周4次的肩部外旋肌力量训练计划。另一个队（n = 6）参加了类似的季前网球训练计划，但未进行任何上肢力量训练。通过比较在Kin-Com等速测力计（Chattecx公司，田纳西州希克森）上进行5次最大离心外旋紧接着向心内旋收缩的训练前后数据，评估了该力量训练计划的效果。总体而言，肩部力量训练计划显著增加了离心外旋的总功，而对向心内旋的总功、向心内旋的平均峰值力或离心外旋的平均峰值力没有显著影响。总之，通过增加离心外旋的总运动能力而不随之增加向心内旋的总运动能力，该力量训练计划可能会减少肩袖肌肉失衡以及从事过头运动的运动员肩部受伤的风险。
