(45) PERFORMANCE DIFFERENCES ON SINGLE LIMB FUNCTIONAL TESTS IN COLLEGE BASEBALL PLAYERS

Purpose: The primary aim of this study was to assess limb symmetry between the throwing and non-throwing limbs using three single-limb functional tests: closed-kinetic chain upper extremity stability test (CKCUEST), upper extremity vertical jump, and lower extremity vertical jump. Secondary aims included examining performance differences between pitchers and position players, as well as between players with a history of shoulder or elbow surgery and those without. Methods: Sixty-eight National Association of Intercollegiate Athletics college baseball players (37 pitchers, 21 with history of shoulder or elbow surgery) volunteered for the study. Participants performed a self-directed warm-up before testing. Tests were conducted in the following order: upper extremity vertical jump, lower extremity vertical jump, and CKCUEST, with a one-minute rest between repetitions and tests. Each assessment included two practice trials and three testing trials, alternating between throwing and non-throwing limbs, with the starting limb selected randomly. Multiple T-tests were used to analyze differences between limbs and limb symmetry, as well as between groups, with a significant level of p < 0.05. Results: Across all baseball players, a significant difference was found with the non-throwing arm performing more repetitions than the throwing arm on the CKCUEST. However, no significant limb differences were observed in the performance of the upper or lower extremity vertical jumps tests. When comparing pitchers to position players, results of the throwing arm CKCUEST trended towards significance, with the position players performing more repetitions than the pitchers. No other significant results were found between pitchers and position players in non-throwing limb performance or limb symmetry on the CKCUEST. The upper and lower extremity vertical jump also did not identify significant differences between pitchers and position players. Lastly, no significant differences were found in any of the three single-limb assessments between athletes with or without a history of shoulder or elbow surgery. Conclusions: The results indicate that across all athletes, the non-throwing arm demonstrates greater stability, as measured by the CKCUEST. Position players demonstrated greater stability with the throwing arm compared to pitchers. Performance on the upper and lower extremity vertical jumps was unaffected by throwing limb, position, or history of upper extremity surgery. Practical Applications: These findings suggest that shoulder stability may be decreased in the shoulder compared to the non-throwing shoulder and this deficit may be greater in pitchers compared to position players when testing college baseball players. Therefore, incorporating closed-kinetic chain shoulder stability exercises into baseball strength and conditioning programs may be necessary to address this asymmetry and improve stability, but more research is warranted. Acknowledgements: None