How kinematics influences shot put results in track and field of international level athletes (a case study)

Abstract

Purpose: The purpose of research was to determine important kinematic variables, which determine result in shot put of international level athlete. Athlete used rotational technique of shot put, which is very demanding from movement coordination point of view. Methods: With MVN Xsens dress with 17 accelerometers (data acquisition 120 Hz) we measured 36 shot puts in 3D and used 276 variables. Result of shot put was measured with IAAF judge’s method. All joint and segment variables – trajectories, velocities, angels and angular velocities in all 3 axis we analysed and the differences between release moment and 0.1 second before release were calculated. Results: With series of regression analysis, we extracted the best predictors and with final stepwise regression explained 47.4% of shotput result, and what is the most important, the best predictors are low (negative) difference of angular velocity in y axe of left upper leg, low (negative) difference of angular velocity in y axe of T12 vertebra, and high difference of left ankle angle to x axe. Conclusion: Importance of opposite throw hand body side, which should be fast deaccelerated and stopped turning in order to give throw arm a rock support for its activity as an open side kinetic chain.