Supraspinatus Tendon Acute Effects After Two Exercise Exposures: a Crossover Randomized Trial.

The purpose of this study is to understand acute tendon changes after two exercise programs. We will invite individuals with and without shoulder pain to participate in this study. Every individual will participate in both exercise programs separated by up to 15 days. The researcher will evaluate the shoulder tendon using ultrasound before each exercise program and at 1 hour, 6 hours and 24 hours after each exercise program. The researcher will also evaluate self reported pain, pain sensitivity testing, and self reported questionnaires. We will compare the tendon changes after each exercise program, as well as between participants with and without shoulder pain.

General inclusion criteria 1. Between 18 and 45 years of age 2. Able to perform physical activity with their shoulder (moderate arm exercise for 15 min, such as tennis or housework) General exclusion criteria 1. Shoulder fracture 2. Frozen shoulder (\>50% restriction in shoulder range of motion) 3. Shoulder surgery 4. Full rotator-cuff tears 5. Bilateral shoulder pain 6. Shoulder instability (history or positive apprehension test) 7. Corticosteroid injection in the last 6 weeks 8. Neurological diseases 9. Cardiological diseases 10. Systemic diseases (rheumatic diseases, autoimmune diseases) 11. Uncontrolled diabetes 12. Pregnancy Group-specific inclusion criteria 1. Shoulder pain group: report unilateral shoulder pain with an average shoulder pain score of≥ 3 in the last week. 2. Control group: report no shoulder pain within 6 months.