Pain management, exercise therapy, electromyography, movement, subacromial impingement syndrome.
Pain management, exercise therapy, electromyography, movement, subacromial impingement syndrome.
Introduction: Rotator cuff tendinopathy is a common shoulder disorder in which the primary treatment is resistance exercises. Isometric exercises are being studied for lower limb tendinopathies but not for rotator cuff tendinopathy. This protocol for a randomized clinical trial aims to compare the effects of two types of exercise (isometric and isotonic) on shoulder pain, function, and neuromuscular control in individuals with rotator cuff tendinopathy. Methods: Forty-six individuals (18 to 45 years old) with shoulder pain for more than three months and unilateral supraspinatus or infraspinatus tendinopathy or both will participate in the trial. Individuals will be randomized into two exercise groups: isometric or isotonic. The following outcomes will be evaluated before and after the first session and after six weeks of intervention: shoulder pain and function; isometric strength of shoulder elevation and lateral and medial rotation; electromyography of medial deltoid, infraspinatus, serratus anterior, and lower trapezius; and scapular kinematics during arm elevation. Groups will perform stretching and strengthening of periscapular muscles. Isometric group will perform three series of 32 s, with 70% of maximal isometric strength. Isotonic group will perform concentric and eccentric exercises (2 s for each phase) in three series of eight repetitions (eight repetition maximum). Total time under tension of 96 s will be equal for both groups, while load will be adjusted in weeks three and five of the protocol. Treatment effect between groups will be analyzed using two-way analysis of variance with repeated measures.