Effect of adding high-intensity strengthening exercises to conventional physiotherapy in athletes with shoulder impingement syndrome: A randomized controlled trial

This study aimed to investigate the effect of adding high-intensity strengthening exercises (HISE) to the conventional physiotherapy program in athletes with shoulder impingement syndrome (SIS). Thirty-two athletes with SIS were randomly and equally assigned into two groups; HISE group (n=16) and conventional physiotherapy group (n=16). The HISE group received both HISE and conventional physiotherapy programs, while the conventional physiotherapy group received only the conventional physiotherapy program. Both groups received a total of 18 sessions at a rate of 3 sessions/week for six weeks. Outcome measures included shoulder function and performance, muscle strength of the external and internal rotators and supraspinatus, acromio-humeral distance at 0° and 90° abduction, and supraspinatus tendon thickness. There was a significant improvement in shoulder performance (p=0.029), shoulder muscle strength of external rotators at 0 abduction (p<0.001) and at 90-90 abduction/external rotation (p<0.001), internal rotators at 0 abduction (p=0.001) and at 90-90 abduction/external rotation (p=0.001), and supraspinatus muscle (p<0.001), acromio-humeral distance at 0 (p=0.031) and 90 degrees of active abduction (p<0.001), and supraspinatus tendon thickness (p=0.009) in the HISE group compared to the conventional physiotherapy group post-treatment. However, no significant difference was observed in shoulder function (p=0.259). It could be concluded that the addition of supervised progressive HISE to the conventional physiotherapy in SIS in athletes improves shoulder performance, muscle strength, acromio-humeral distance, and supraspinatus tendon thickness.