Professional Baseball Pitchers Use of Weighted Ball Training, Injury Incidence, and Time Loss: A Preliminary Study

Background Little is known about the injury risk associated with weighted ball use by professional baseball pitchers. The purpose of this study was to describe weighted ball training and injuries and compare injury rates between those professional pitchers using weighted ball training and those that did not use weighted ball training during the 2023 pre- and regular season. Methods This study, intended as a multi-year project, serves as an interim safety analysis after one year of follow up. Pitchers underwent routine physical examination and injury screening and were surveyed about their use of weighted baseball training. Throughout spring training and the Minor League Baseball (MiLB) season, all pitchers were monitored daily for athletic exposures and injuries. The outcome of interest was non-traumatic baseball injuries to any tendon, ligament, nerve, muscle, or bone that occurs during any baseball team sponsored activity or event that was confirmed by the team athletic trainer. Injury rates per 1000 game exposures (GE) was calculated by weighted ball use and grouped by body part. Results Eighty-eight pitchers were included (Weighted Ball: n = 46; No Weighted Ball: n = 42) A total of 28 injuries were reported ((Upper extremity=20 (Shoulder Injury:9; Elbow Injury 11); Trunk/Core=8; Lower Extremity=0). Pitchers that used weighted ball training suffered eight more injuries at a 1.1 greater injury rate per 1,000 athlete exposure days compared to pitchers that did not use weighted ball training. Weighted ball pitchers arm injury rate was 11.8 per 1000 GE, and no weighted ball arm injury rate was 7.5 per 1000 GE. Weighted ball pitcher trunk injury rate was 5.9 per 1000 GE, and no weighted ball trunk injury rate was 2.1 per 1000 GE. Conclusions In this interim safety analysis, professional pitchers that performed weighted ball training suffered from greater arm and core/trunk injuries compared to professional pitchers that did not perform weighted ball training. Level of Evidence 3