Countermovement Jump Force Plate Kinetics In Collegiate Athletes With Overuse Injury Symptoms

PURPOSE: Countermovement jump (CMJ) testing is common to assess athlete health status and performance capability, but there is minimal empirical data to indicate which CMJ outcome measures will aid in determining health status. The purpose of this study is to determine the differences in CMJ outcome measures between collegiate athletes complaining of no, mild, moderate, and severe overuse symptoms. METHODS: Ninety-four collegiate athletes (F = 59, M = 35, age: 21.3 ± 1.7 years, height: 174.2 ± 8.7 cm, mass: 71.7 ± 8.0 kg) participated in preseason and midseason testing around their fall competitive season. Participants completed three CMJ trials on a triaxial force plate and then completed the Oslo Sports Trauma Research Centre Overuse Injury Scale (OSTRC). Twenty-two outcome measures were captured from the CMJ trials and used for analysis. Participants were grouped via outcome scores on the OSTRC into groups of no symptoms (OSTRC = 0), mild symptoms (OSTRC = 1-14), moderate symptoms (OSTRC = 15-28), or severe symptoms (OSTRC = 28-100). The CMJ outcome scores were compared across the groups with linear mixed models, and sex and OSTRC group were predictor variables. Participant mass was used as a covariate for all analyses. RESULTS: There was a significant interaction between sex and OSTRC group for jump height by flight time (F = 3.08, p = 0.029). Females with severe symptoms demonstrated lower jump height compared to those with mild problems (t = 2.76, p = 0.034) and moderate problems (t = 2.99, p = 0.018). Peak force was significant different across OSTRC groups regardless of sex, with the no problems group demonstrating the lower peak force compared to the moderate group (t = 2.94, p = 0.019). CONCLUSIONS: Jump height demonstrates to be predictive of changes in OSTRC in females and is different between participants when they demonstrate different OSTRC symptoms. Peak force was also different between groups, with those with no symptoms demonstrating less force, despite getting similar jump heights. Individuals with no symptoms may be more efficient with their movement, thus allowing them to get to higher jump heights despite lower force. Overall, more studies need to be performed to ensure that CMJ outcome measures are predictive of health status before deploying this testing widely in clinical care. NATA New Investigator #2021NIP01