Multijoint Coordination Contributes to the Minimization of Frontal Plane Center-of-Mass Displacement in Maximal Velocity Sprinting.

Previous studies on sprinting biomechanics have identified a variety of biomechanical characteristics that describe the outcome of improved sprint technique but in doing so have neglected to identify the postural control strategies that lead to improved sprint performance. The purpose of this study was to evaluate the relationship between frontal plane displacement of the center of mass (CoM) and sprint velocity, and to understand if multijoint coordination of the limbs and trunk were associated with minimizing the displacement. The results from this study suggest that stance phase frontal plane CoM cumulative path length is significantly associated with sprint velocity. Further, a multivariate linear regression model revealed that coordinative couplings of the bilateral limbs and trunk were associated with the minimization of the frontal plane CoM displacement. Specifically, the coordination of the knees (flexion-extension) and axial rotation of the thorax-pelvis were the most important interjoint couplings in minimizing frontal plane CoM displacement. Frontal plane CoM displacement provides coaches, athletes, and performance professionals with an interpretable metric to identify sprint technique quality in field using wearable sensors. Future work needs to further advance our understanding of postural control during sprinting so that effective coaching and rehabilitation interventions can be designed.