Joint contact forces of the lower extremity during straight and curve sprinting

Abstract-Text (inkl. Referenzen und Bildunterschriften)

Introduction

While kinematic analysis of sprinting is ubiquitous, the kinetics remain understudied, even though they could be used to target injury prevention [1].

Study Aim

We investigate differences in shear joint contact forces (F_xy=√F_x²+F_y²) of the hip, knee, and ankle between curved and straight-line sprinting. Additionally, the effect of curve radius and left/right leg differences are examined.

Methods

Twelve experienced track & field athletes sprinted 100m in a straight line, the inner curve and the outer curve. Each condition was performed twice. Kinematics were recorded using a full-body motion capture suit (Xsens Link, version 2021.2, Movella Inc., Henderson, U.S.A). The musculoskeletal model Myonardo® (version 6.2.9, Predimo GmbH, Münster, Germany) was used to estimate peak F_xy of the joints. Data was normalised to subjects body weight and examined using a generalised linear mixed model.

Results

Analysis revealed sig. differences in F_xy of the ankle between conditions, with F_xy being higher during curved compared to straight sprinting (Fig.1). Hip and knee showed no sig. differences between the conditions.

Fig.1: F_xy of the ankle joint; comparison of the three conditions. Braces with asterisks indicate a significant difference (*p<.05, **p<0.01, ***p<0.001).

Additionally, there are sig. differences in F_xy for the hip and knee between the left and right leg, with F_xy being higher for the outside leg during curve sprinting (Fig.2). No sig. differences were found for the ankle joint.

Fig.2: F_xy of the hip (top) and knee joint (bottom); comparison of the two body sides.

Conclusion

We find sig. different shear forces in the ankle joint, but not in the hip and knee joints, during curve sprinting compared to straight-line sprinting. Additionally, there are sig. differences between left and right shear forces in the hip and knee joints, but not in the ankle joint. Results can be used for training adaptation and thus possible injury prevention.

References

Edwards, W. B., Modeling Overuse Injuries in Sport as a Mechanical Fatigue Phenomenon. Exercise and Sport Sciences Reviews, 46(4), 224–231, 2018.