Development of Mechanism to Support Waist Rotation in Sprint Running for Improving Coordination Between Trunk and Pelvis

Abstract

Recently, there are a lot of researches to analyze motion in sports to improve motor skills. It is hard to learn ideal movement by simply analyzing data especially in sprint running, which requires complex movements in a short period of time. In this research, the authors have worked on the method to acquire the aimed movement through physical experience. In sprint running, it is said that the coordination between trunk and pelvic rotation generates more efficient horizontal floor reaction force for increasing speed. Therefore, we devised two experimental devices to reduce the phase difference between trunk and pelvic rotation. The first one is tension applying device to increase muscular activity for pelvic rotation with force by pulling a wire attached to both sides of the waist. Second one is skin shear deformation device to support fine adjustment of pelvic rotation by applying shear force to skin around pelvis. We confirmed that these devices satisfied experimental requirements, and it was suggested that the devices could have an effect on the waist rotation for sprint running.