Effects of plyometrics and conventional resistance exercise in a rotator cuff strengthening program for women with shoulder impingement syndrome

Objective: Shoulder impingement syndrome is a common cause of rotator cuff–related shoulder pain, and exercise-based rehabilitation focusing on rotator cuff and scapular stability is widely used. To compare the effects of plyometric exercise and conventional resistance exercise on shoulder function, stability, and grip strength in women with shoulder impingement syndrome. Design: Randomized controlled parallel-group trials. Methods: Thirty-two office workers (aged 20–40 years) diagnosed with shoulder impingement syndrome were randomly allocated to a plyometric exercise (PE) group or a conventional resistance exercise (CRE) group. Both groups performed 2 weeks of isometric rotator cuff exercises followed by 4 weeks of either plyometric rotator cuff training or traditional resistance–based rotator cuff strengthening, twice weekly for 20 minutes (total 6 weeks). Outcomes were the Korean Shoulder Pain and Disability Index (K-SPADI), closed kinetic chain upper extremity stability test (CKCUES), and grip strength. Twenty-eight participants completed the study. Results: Both groups showed significant improvements in K-SPADI and CKCUES scores after the intervention (p < 0.05), with no significant between-group differences (effect sizes 0.315 and 0.291, respectively). Grip strength increased significantly in both groups, but the PE group showed a greater improvement than the CRE group (p < 0.05; effect size 1.683). Conclusions: Plyometric and conventional resistance exercises were both effective in improving shoulder pain, function, and stability in young women with shoulder impingement syndrome. Plyometric training produced superior gains in grip strength and may be considered a useful alternative or adjunctive approach in shoulder rehabilitation.