(42) CORRELATIONS BETWEEN COUNTERMOVEMENT JUMP, DROP JUMP AND HORIZONTAL DECELERATION ABILITY IN NCAA DIVISION 1 FEMALE SOCCER ATHLETES

Purpose: The purpose of this study was to examine the correlations between countermovement jump, drop jump and horizontal deceleration ability in NCAA Division 1 female soccer athletes. Methods: A cross-sectional research study design was used to examine the association between drop jump from a 20-centimeter box (DJ20), countermovement jump (CMJ), and average horizontal deceleration (HDEC). Thirty-three division 1 female soccer players volunteered to participate in this study. Following a standardized warm up on an indoor turf practice facility, two maximal sprint times were recorded over 20-meter distance using timing gates. Participants then completed three acceleration deceleration ability (ADA) tests, which required them to maximally decelerate at the end of a maximal 20 m sprint and then backpedal past the 20 m line (1). Only trials where entrance speed was within 5% of maximal 20 m sprint time were accepted. Instantaneous horizontal velocity was measured throughout the test using a radar device connected to a laptop with the Stalker ATS system software for data acquisition. Deceleration variables evaluated were HDEC, average early deceleration (EDEC), average late deceleration (LDEC) and average ratio (EDEC/LDEC). The point immediately following the maximum velocity to the lowest velocity following the maximum was considered the full deceleration phase; EDEC was defined by the start of the deceleration phase to 50% of the maximum velocity, and LDEC was defined by the point following the 50% mark to the end of the deceleration phase. Post field testing, participants completed two CMJ trials and six DJ assessments on dual-force plate platforms. Pearsons’s correlation analysis was used to determine the relationship between the CMJ, DJ and deceleration variables. Data was analysed using Microsoft Excel. Results: The correlation analysis showed a positive correlation between DJ peak drive-off (active) force and average LDEC (r=0.55) and average ratio (r=0.79). There was also a positive correlation between DJ reactive strength index and LDEC (r=0.46) as well as average ratio (r=0.67). There was a negative correlation between DJ jump height and HDEC (r=-0.41), and distance to stop (r=0.71). No significant correlations were seen between the CMJ variables and the deceleration metrics. Conclusions: Selected DJ variables showed moderate to large correlations to LDEC and average ratio deceleration variables, providing insight into potential underpinning qualities of late-stage deceleration and deceleration phase ratio in female athletes. Practical Applications: Horizontal deceleration is a critical and highly demanding action in soccer. To train and improve deceleration ability, incorporating DJ training might be beneficial for female soccer athletes. Acknowledgements: The authors would like to thank the participating athletes and universities for their contributions to this study.