An Exploratory Analysis of Countermovement Jump Variables Between Higher and Lower Performers on the LESS and...

Identifying movement dysfunction is critical for optimizing training and injury risk. While functional movement assessments like the Y-Balance Test (YBT) and the Landing Error Scoring System (LESS) are widely used, they require dedicated personnel, time, and testing space. The relationship between performance on movement assessments and the countermovement jump (CMJ) variables is unknown.

The purpose of this study was to explore the relationship between CMJ force plate metrics and performance on the YBT and LESS in collegiate athletes. It was hypothesized that CMJ variables would differ between high- and low-performing athletes on the YBT and LESS.

Prospective observational cross-sectional study.

Male and female NCAA Division I athletes aged 18-21 years (n = 109) completed the YBT and LESS using standard protocols, and the CMJ on a validated portable force plate during the off-season as part of routine performance monitoring. Movement assessments independently stratified athletes into high- and low-performing groups. Group differences in CMJ metrics of jump height, Left/Right (L/R) peak propulsive force, landing stiffness, peak landing force, L/R average landing force, L/R landing impulse, reactive strength index modified (mRSI), and propulsive phase duration were analyzed using t-tests or Wilcoxon signed-rank tests.

Athletes with LESS scores >5 demonstrated significantly greater landing stiffness (mean = -9757.73 ± 16231.15 N/m) compared to those scoring ≤5 (mean = -6555.38 ± 3515.67 N/m) (p = 0.01). Athletes with an anterior limb reach difference > 4 cm on the YBT had higher mRSI (p = 0.004), propulsive phase (p = 0.004), and peak landing force (p = 0.002).

Some CMJ metrics vary by performance on the YBT and LESS, offering insight into movement quality in collegiate athletes. While further research is needed to establish direct links to outcomes, these findings support CMJ testing as a practical, objective complement to traditional movement assessments.

Level 3.