Analyzing Vertical Ground Reaction Forces And Coordination Of Medial Lateral Ground Reaction Forces In Jumping

Jumping is a dynamic movement dominant in many sports and used in athletic assessment; however, there is minimal knowledge comparing vertical ground reaction forces (VGRF) and coordination with medial lateral ground reaction forces (MLGRF) in jump height (JH). PURPOSE: To measure the level of in-phase (IP) and out-of-phase (OP) coordination between VGRF and MLGRF using continuous relative phase (CRP) and estimated jump height performance. METHODS: Thirty-six professional soccer players (20.78 ± 1.67 yrs, 176.82 ± 8.97 cm, 73.98 ± 10.10 kg) were included in this study. Manual muscle tests were conducted prior to jumping protocol. Three bilateral counter-movement jumps (CMJ), two right single-leg counter-movement jumps (RSL), and two left counter-movement jumps (LSL) were performed on bilateral force plates. Participants were instructed to pause prior to each jump. Univariate linear regression model examined relationship between Total VGRF vs Total MLGRF RMS CRP and Jump Height. Figure 1 shows the comparison between Total VGRF and Total MLGRF for a single countermovement jump with the calculated CRP. RESULTS: Total VGRF vs Total MLGRF RMS CRP was not predictive of jump height (R2 = -2.227), suggesting a non-linear relationship between the two variables. CONCLUSION: This pilot study examined jump height in professional athletes. Preliminary results do not suggest a significant correlation between Total VGRF vs Total MLGRF RMS CRP and estimated jump height. Future research examining multiple predictors of jump height or looking at each leg individually (right vs. left) is warranted.