COUNTERMOVEMENT JUMP METRICS AND THEIR RELATIONSHIP TO SWING PERFORMANCE IN NCAA DIVISION III SOFTBALL AND BASEBALL PLAYERS

K. Alvarenga-Beech, J. Sedy, G. Jackson, C. Reyes Linfield University, McMinnville, OR High swing speed for hitters can be seen as an advantage. A faster swing leads to longer decision-making time, as well as the possibility of harder-hit balls, which all increases hitting success. With the variety of assessments in human performance, certain ones possess more of a predictive quality with other skills and tests. The countermovement jump (CMJ) is a common test used across performance and rehabilitation and has demonstrated the ability to relate with other skills. PURPOSE: The purpose of this study was to discover predictive values of CMJ kinetics to swing speed in collegiate-level softball and baseball players. METHODS: Student-athletes from NCAA Division III softball and baseball teams were utilized in this study (N = 43; 25 males and 18 females). All were considered healthy and full participants of their respective team training sessions. Participants reported to the lab for one, 30-minute testing session. Following a standardized warm-up, four no-arm CMJ were recorded on a force plate and these metrics were collected: jump height (JH), Average Relative Propulsive Force (APF), Peak Relative Propulsive Force (PPF), Positive Net Impulse (PNI), and Reactive Strength Index – Modified (mRSI). Their best CMJ, as defined by highest JH, was used in the analyses. Following their CMJ trials, each participant performed their respective softball/baseball swing, where they were instructed to swing as hard as they could. Bat Speed (BS) and Time to Contact (TC) were measured during 20 swings and their highest BS and TC were used in the analyses. Multiple regressions were utilized to analyze the relationships between the predictor variables of CMJ metrics to swing metrics. RESULTS: Significant relationships were discovered between BS and all CMJ metrics except PPF (R2 = 0.22 - 0.44, p \u3c 0.05), while all CMJ metrics significantly related to TC (R2 = 0.18 - 0.3, p \u3c 0.001). CONCLUSIONS: The data provides evidence that metrics in CMJ are predictor qualities to swing with high speed. Therefore, utilizing the CMJ test for softball and baseball coaches can provide insight into their ability to swing a bat with high output, as well as data for performance coaches to improve CMJ kinetics to ultimately lead to enhanced swing performance