On-the-field resistance-tubing exercises for throwers: An electromyographic analysis

Context: Athletes who throw commonly use rubber-tubing resistance exercises in the field setting to assist with warm-up before throwing. Yet no researchers have described which muscles are being activated or which exercises are most effective during rubber-tubing exercises used by throwers for warm-up. Objective: To describe the effectiveness of 12 rubber-tubing resistance exercises commonly used by throwers in activating the shoulder muscles important for throwing. Design: Descriptive research design. Setting: An applied biomechanics research laboratory. Patients or Other Participants: Fifteen physically active male subjects with no history of shoulder injury. Main Outcome Measure(s): Subjects randomly performed 12 rubber-tubing resistance exercises while we assessed muscle activation of the subscapularis, supraspinatus, teres minor, and rhomboid major by indwelling electromyography. Activation of the sternal portion of the pectoralis major, anterior deltoid, middle deltoid, latissimus dorsi, serratus anterior, biceps brachii, triceps brachii, lower trapezius, and infraspinatus muscles was assessed by surface electromyography. Results: Performance of 7 exercises (external rotation at 90° of abduction, throwing deceleration, humeral flexion, humeral extension, low scapular rows, throwing acceleration, and scapular punch) resulted in the highest level of muscle activation of all muscles tested. Conclusions: These 7 exercises exhibited moderate activation (>20% maximal voluntary isometric contraction) in each muscle of the rotator cuff, the primary humeral movers, and the scapular stabilizer muscles. The results suggest that these exercises are most effective in activating the muscles important to the throwing motion and may be beneficial for throwers during their prethrowing warm-up routine.