INTRODUCTION AND PURPOSE: The shoulder complex muscles play an important role in force, power and endurance production in volleyball, allowing the accomplishment of movement in a coordinated manner. The objective written account produced by isokinetic evaluations assists in the diagnosis and prevention of shoulder complex injuries. In addition, it is a useful tool in promoting safe and fast return of the injured athlete to sports practice. The purpose of this study was to analyze the isokinetic muscle performance of the lateral and medial rotators of the glenohumeral joint in Brazilian male volleyball teams (under-19 and under-21). METHODS: The protocol used during the test included five maximum repetitions of shoulder lateral and medial rotation in concentric-concentric mode at 60º/s and 30 repetitions at 360º/s. Analysis of variance was used to evaluate the dependent variables: maximum work and maximum torque of shoulder lateral and medial rotators normalized by body mass, antagonist/agonist ratio at the two speeds and muscular fatigue index. RESULTS: Data analysis demonstrated an imbalance between the shoulder lateral and medial rotators (antagonist/agonist ratio) in the under-21 category of the Brazilian volleyball athletes, demonstrating relative weakness of the lateral rotators. CONCLUSION: It was possible to identify changes in volleyball players, which added to specific demands of the sport, can lead to symptoms in the shoulder complex and / or decrease of performance.
shoulder; torque; athletic injuries
