The Acute Impacts on Countermovement Jumping Metrics Following an Exhibition Soccer Match

Abstract

Countermovement jump (CMJ) force-time assessments via force plates, are a quick and accurate way to measure a multitude of variables. However, the reporting of variables without specific groupings (strategy, driver, other) could hinder accurate interpretation of said metrics.  The present study aimed to assess CMJs before and after a competitive off-season soccer scrimmage, aiming to see if any specific groupings were impacted, helping to expand on potential variables relating to neuromuscular fatigue (NMF). Methods: Fourteen division II female soccer players (mean ± SD: age = 19.20 ± 1.01years) performed three hands on hips countermovement jumps on a dual-force plate system before and after a competitive off-season soccer exhibition. Results: For strategy metrics, significant differences were seen for the braking phase and propulsive phase (shorter time spent post-game) (p = 0.010 – 0.039).  Shallower countermovement depth occurred post vs. pre-game (p = 0.004).  For the driver metrics, no differences were seen for any RFD, force, velocity or power variables (p = 0.060 – 0.551).  Lastly, jump momentum was the only outcome metric that reported significant differences (p = 0.004) (lower post- vs. pre-game).  Conclusions: The present study observed greater deficits in strategy (braking, propulsive phase, countermovement depth) and outcome metrics (jump momentum), rather than drivers (power, force, velocity). While deficits in athletic performance within and post-game can be multi-faceted, the present findings highlight the importance for assessing different groupings and not just driver metrics, when assessing CMJ force-time metrics and potential fatigue.