Neuromuscular Recruitment and Interlimb Asymmetry During Shoulder Prevention Exercises with Elastic Resistance in Tennis Players

Shoulder injuries are highly prevalent in tennis due to repetitive unilateral loading and the asymmetrical demands of the sport. Preventive protocols often focus on scapular stabilizers, yet evidence on muscle recruitment patterns during unilateral elastic re-sistance exercises remains limited. This study compared trapezius activation and asymmetry in tennis players (n = 16) and non-tennis athletes (n = 23) during unilateral scapular retraction exercises at 45° and 90° of shoulder abduction. Surface electromyog-raphy recorded bilateral activity of the middle and lower trapezius using a validated wireless system. Repeated-measures ANOVA was applied to examine the effects of angle, dominance, side, and athlete type. Results showed significantly greater activation at 90° compared to 45° (p < 0.05) and pronounced interlimb asymmetries between dominant and non-dominant sides (p < 0.01). Tennis players exhibited higher non-dominant trapezius activation, suggesting compensatory adaptations to repetitive unilateral strokes, whereas non-tennis athletes demonstrated more symmetrical recruitment. These findings high-light the role of elastic resistance exercises in selectively engaging scapular stabilizers, addressing sport-specific asymmetries, and reducing injury risk in overhead athletes.