RESUMEN
PURPOSE: Seeking a method to evaluate and monitor the performance of the shot put, discus and javelin throw, we analyzed the transfer of mechanical energy between body segments. METHODS: The study was conducted on groups consisting of elite throwers on the Polish National Team for each of the aforementioned sport disciplines. The movements of each throw were recorded using Vicon system and Kistler plates. The power and energy fluctuations were computed for the final acceleration phase of each throw. RESULTS: In all three disciplines studied, we found an average energy loss of 1.63 J/kg generated from shoulder to wrist. The value of generated energy from ankle to torso initially increased in all disciplines, followed by a descent - with the exception of the javelin throw, where there was an average 27% decrease in both hip joints. We found strong correlations between relative amplitude values of energy and the athlete's personal performance records: -0.8226 (shot put), 0.6008 (discus) and 0.7273 (javelin). CONCLUSIONS: Measuring the transfer of mechanical energy between body segments offers a useful method for evaluating the technique of ballistic movements and for monitoring training progress.
Asunto(s)
Rendimiento Atlético , Movimiento , Atletismo , Atletas , Fenómenos Biomecánicos , Humanos , Articulaciones/fisiología , Adulto JovenRESUMEN
The aim of this study was to analyse transfer of mechanical energy between body segments during the glide shot put. A group of eight elite throwers from the Polish National Team was analysed in the study. Motion analysis of each throw was recorded using an optoelectronic Vicon system composed of nine infrared camcorders and Kistler force plates. The power and energy were computed for the phase of final acceleration of the glide shot put. The data were normalized with respect to time using the algorithm of the fifth order spline and their values were interpolated with respect to the percentage of total time, assuming that the time of the final weight acceleration movement was different for each putter. Statistically significant transfer was found in the study group between the following segments: Right Knee - Right Hip (p = 0.0035), Left Hip - Torso (p = 0.0201), Torso - Right Shoulder (p = 0.0122) and Right Elbow - Right Wrist (p = 0.0001). Furthermore, the results of cluster analysis showed that the kinetic chain used during the final shot acceleration movement had two different models. Differences between the groups were revealed mainly in the energy generated by the hips and trunk.