Asymmetries of foot strike patterns during running in high-level female and male soccer players

Stanislav Dimitri Siegel; Joel Mason; Daniel Hamacher; Anna Lina Rahlf; Astrid Zech

doi:10.1186/s13102-023-00696-2

Asymmetries of foot strike patterns during running in high-level female and male soccer players

BMC Sports Sci Med Rehabil. 2023 Jul 14;15(1):86. doi: 10.1186/s13102-023-00696-2.

Authors

Stanislav Dimitri Siegel¹, Joel Mason², Daniel Hamacher³, Anna Lina Rahlf⁴, Astrid Zech²

Affiliations

¹ Department of Human Movement Science and Exercise Physiology, Institute of Sport Science, Friedrich Schiller University Jena, Seidelstraße 20, Jena, 07749, Germany. stanislaw.siegel@uni-jena.de.
² Department of Human Movement Science and Exercise Physiology, Institute of Sport Science, Friedrich Schiller University Jena, Seidelstraße 20, Jena, 07749, Germany.
³ Methods and Statistics in Sports, Institute of Sport Science, Friedrich Schiller University Jena, Seidelstraße 20, Jena, 07749, Germany.
⁴ Department of Sports Science, Institute of Health, Nutrition and Sport Science, Europa-Universität Flensburg, Campusallee 2, Flensburg, 24943, Germany.

Abstract

Backround: Foot strike pattern (FSP) is defined by the way the foot makes initial ground contact and is influenced by intrinsic and extrinsic factors. This study investigated the effect of running speed on asymmetries of FSP.

Methods: Seventeen female and nineteen male soccer players performed an incremental running test on an instrumented treadmill starting at 2.0 m/s until complete exhaustion. Force plate data were used to categorize foot strikes into rearfoot (RFS) and non-rearfoot strikes. Additionally, peak vertical ground reaction force (peakGRF) and stride time were calculated. The symmetry index (SI) was used to quantify lateral asymmetries between legs.

Results: The SI indicated asymmetries of the rate of RFS (%RFS) of approximately 30% at slow running speed which decreased to 4.4% during faster running speed (p = 0.001). There were minor asymmetries in peakGRF and stride time at each running stage. Running speed influenced %RFS (p < 0.001), peakGRF (p < 0.001) and stride time (p < 0.001). Significant interaction effects between running speed and sex were shown for %RFS (p = 0.033), peakGRF (p < 0.001) and stride time (p = 0.041).

Conclusion: FSP of soccer players are asymmetric at slower running speed, but symmetry increases with increasing speed. Future studies should consider that FSP are non-stationary and influenced by running speed but also differ between legs.

Keywords: Asymmetry; Foot strike pattern; Running; Sex; Soccer.