Many athletes are required to perform high intensity (HI) movements unilaterally and bilaterally. Force plate technology can measure is capable of quantifying performance during HI movements, such as vertical jump (VJ), as well as any asymmetries involved in the movement, but limited data using this modality is currently available. PURPOSE: The purpose of this study is to present descriptive data of VJ height, left and right leg braking symmetry (L/R-S), and modified reactive strength index (mRSI) during a no-hand countermovement VJ (CMJ) measured using a force plate on male (M) and female (F) Division I athletes. METHODS: Forty-nine M lacrosse players (MLAX; age: 20.0 ± 1.6 y; height: 182.0 ± 6.3 cm), 28 F lacrosse players (WLAX; age: 19.5 ± 1.6 y; height: 165.7 ± 3.8 cm), 31 M baseball players (BB; age: 20.0 ± 1.7 y; height: 183.1 ± 9.8 cm), 19 F softball players (SB; age: 19.7 ± 1.6 y; height: 169.8 ± 7.0 cm), 7 M tennis players (MTN; age: 20.6 ± 1.5 y; height: 181.8 ± 8.9 cm), and 11 F tennis players (FTN; age: 20.1 ± 1.3 y; height: 163.7 ± 8.9 cm), completed a no-hands countermovement VJ test on a force plate system. Jump height, L/R-S (0 being symmetrical, negative values indicate more force applied through the right foot and more positive indicates the same for the left foot), and mRSI were recorded using mean ± standard deviation. VJ testing was conducted during pre-season following physician clearance. RESULTS: VJ height for M was highest in BB (40.2 ± 7.3 cm) and lowest in MTN (33.8 ± 3.9 cm). VJ height for F was highest in SB (26.3 ± 4.3 cm) and lowest in WTN (23.3 ± 5.3 cm). The largest discrimination between L/R-S was seen for M in BB (-5.5 ± 13.9) with the smallest in MLAX (-1.29 ± 14.45). For F the largest L/R-S was seen in WTN (-2.86 ± 15.34) and the smallest in SB (0.44 ± 7.09). BB had the highest mRSI (0.50 ± 0.08) and MTN had the lowest (0.36 ± 0.12) in M. SB had the highest mRSI in F (0.36 ± 0.05) with WTN showing the smallest (0.29 ± 0.15). CONCLUSION: The differences seen in VJ data between sports and gender may be explained by the specific demands placed on the body during competition. This data may be able to provide strength and conditioning coaches and other sports medicine professionals insight into common trends related to explosive power and L/R-S in each sport to provide more specialized training to address potential asymmetries and target VJ goals.
Krawczyk, Matthew; Saldutti, Dominick; Melgar, Douglas; Gerland, Roger; Ghigiarelli, Jamie; Gonzalez, Adam; Shaver, Kelly; and Sell, Katie
"Force Plate Determined Jump Height, Braking Symmetry, and Reactive Strength Index in Collegiate Athletes,"
International Journal of Exercise Science: Conference Proceedings: Vol. 15:
3, Article 3.
Available at: https://digitalcommons.wku.edu/ijesab/vol15/iss3/3