(12) A PRELIMINARY ANALYSIS OF NEUROMUSCULAR FUNCTION AFTER A SIMULATED SOCCER MATCH IN FEMALE SOCCER PLAYERS

Jump testing is commonly used to assess athletes’ neuromuscular function and lower body power. These tests are time-efficient and non-fatiguing and are often used to make informed decisions regarding athlete readiness upon return from injury. It is becoming more common for coaches and practitioners to employ these tests to assess recovery from previous training sessions. However, certain tests may be more sensitive to fatigue and therefore more useful in the field.

Purpose: The purpose of this study was to assess changes in both bilateral and unilateral lower-limb power metrics after a simulated soccer match in female collegiate soccer players. It was hypothesized both bilateral and unilateral power would decline due to the fatiguing exercise bout.

Methods: Female collegiate soccer athletes (N=16; Age_mean=19 ± 1 yr) participated in this study. Baseline (pre-fatigue) jump height was assessed after a brief dynamic warmup. Athletes then performed a 90-minute simulated soccer match on a treadmill. Jump assessments were repeated immediately following the treadmill protocol to determine the effects of fatigue on neuromuscular function. This was assessed by bilateral and unilateral countermovement jumps (CMJ) and drop jumps (DJ) using portable force plates (Hawkin Dynamics). Athletes performed two bilateral jumps followed by two single-leg (SL) jumps on each leg for both CMJ and DJ with 30 seconds rest between trials. Jump height (cm) was recorded for each jump and the average of the two trials was used for analysis. Changes in jump height from pre- to post-fatigue were determined using paired t-tests, and an alpha level of 0.05 to determine statistical significance.

Results: There were no significant differences in bilateral CMJ (Pre: 27.9 ± 3.1 cm; Post: 27.8 ± 3.5 cm; P=0.82) or DJ height (Pre: 28.4 ± 5.2 cm; Post: 27.6 ± 4.9 cm; P=0.38) pre- and post-fatigue. There were no differences in SL CMJ height for both dominant (Pre: 13.4 ± 2.4 cm; Post: 13.5 ± 2.8 cm; P=0.99) and non-dominant legs (Pre: 14.4 ± 2.0 cm; Post: 14.2 ± 2.1 cm; P=0.44), but there were significant declines in SL DJ height from pre- to post-fatigue for both dominant (Pre: 8.2 ± 2.8 cm; Post: 6.6 ± 2.6 cm; P< 0.001) and non-dominant legs (Pre: 8.6 ± 2.3 cm; Post: 7.3 ± 2.8 cm; P=0.008).

Conclusions: A treadmill-based simulated soccer match elicited decreases in single-leg DJ height in both dominant and non-dominant legs. The increased muscular challenge of the DJ compared to CMJ may make DJ a more sensitive measure of neuromuscular fatigue than CMJ. Additionally, it may be important to isolate each leg when assessing neuromuscular fatigue. PRACTICAL APPLICATIONS: Coaches may consider using single-leg drop jumps to assess lower-body power and neuromuscular function, as isolating each leg may create a more sensitive measure compared to bilateral assessments. The added muscular demand from the DJ compared to CMJ may also allow coaches to identify athlete readiness in high-level athletes who can often continue to perform under fatigued conditions.


Acknowledgements: This work is partially supported by an ASPIRE grant from the Office of the Vice President for Research at the University of South Carolina.

This abstract was made possible in part by Grant Number T32-GM081740 from NIH-NIGMS. Its contents are solely the responsibility of the authors and do not necessarily represent the official views of the NIGMS or the NIH.