Static Stretching may have Immediate Positive Effects on Hip Kinematics and Ball Velocity in Baseball Pitching; a Prospective Pilot Case Series

Hip muscular tightness is thought to be associated with suboptimal pitching kinematics and shoulder injuries in baseball. Although hip stretching is generally recommended, its immediate effects on hip kinematics and ball velocity in baseball pitching is unknown. The purpose of this pilot study was to investigate the immediate effects of static stretching on hip kinematics and ball velocity. 10 young male participants (age, 19.7 ± 0.6 years; height, 170.5 ± 6.2 cm; weight, 64.0 ± 5.9 kg; body mass index, 22.1 ± 1.5) participated in this prospective case series. Hip kinematics and ball velocity were assessed before and after stretching interventions aimed for hip flexors and adductors. As a result, there was a significant increase in peak hip abduction range of motion (ROM) on the stride side (p<0.05), however not in peak hip abduction ROM or extension ROM on the trail side. Mean ball velocity improved significantly after stretching interventions (p<0.05). In conclusion, hip static stretching may be beneficial to improve hip dynamic ROM during baseball pitching and ball velocity in the short term. Further studies with more rigorous methodologies are required to test the hypotheses developed in this pilot study.

Keywords: Baseball pitching, Static stretching, Hip kinematics, Ball velocity.