Effects of stretching programme on functional shoulder performance in volleyball players with posterior shoulder tightness

The aim in this study was to investigate the effects of a six-weeks long stretching programme on the viscoelastic properties of posterior shoulder muscles, shoulder functional performance and range of motion in volleyball players with posterior shoulder tightness. The study was conducted with 34 male professional volleyball players with posterior shoulder tightness, aged between 19 and 26. The players were randomly assigned into stretching (ages: 22±2 years; Body Mass Index (BMI): 22.1±0.9 kg/m2) and control (ages: 20±0.9 years; BMI: 22.1±1.4 kg/m2) groups. A stretching routine combining sleeper stretch (SS) and cross body stretch (CBS) exercises was applied to the stretching group for 6 weeks, while no intervention was applied to the control group. Measurements were taken during the first assessment and 6 weeks after the treatment for the following: Shoulder external and internal rotation range of motion, spike velocity, seated single arm shot put test, isokinetic measurement of shoulder internal and external concentric muscle strength at 60°/sec ve 300°/sec angular velocities, and infraspinatus – posterior deltoid muscle stiffness by elastography. 2x2 Factorial ANOVA was used as a statistical test method. The P-value threshold for statistical significance was accepted as less then 0.05. At the end of 6 weeks, the stretching programme was found to have had a statistically significant effective on increasing the range of motion of the shoulder in terms of internal rotation (p<0.01), spike velocity (p=0.03) and seated single arm shot put distance (p<0.01). However, the stretching programme was not found effective on shoulder internal and external concentric muscle strength at 60°/sec ve 300°/sec angular velocities and tissue hardness. In conclusion, it was observed that a stretching programme of at least 6 weeks and consisting of SS and CBS exercises was effective on improving range of motion of shoulder internal rotation and especially on explosive force for professional volleyball players with posterior shoulder tightness.