Factors influencing snatch performance in elite weightlifters

<p dir="ltr">In the snatch, an athlete's success is dictated by the mass they are able to lift and hold overhead in one smooth movement. Optimal technique during the pull has only been hypothesized from collected barbell trajectory and joint kinematic data of top athletes. The use of experimental data to understand techniques of elite lifters and how they vary offers some insight but does not provide much information on how these lifters should improve. The aim of this study was to use a torque-driven computer simulation model of the snatch in order to identify factors that influence individual performance in the snatch using a theoretical approach.</p><p dir="ltr">An 8-segment subject-specific torque-driven computer simulation model of the snatch was developed. Torque generators were included at the MTP, ankle, knee, hip, shoulder, elbow and wrist joints, based on strength data collected from an elite weightlifter. Performance and anthropometric data were collected from 14 internationally competitive weightlifters including the individual the model was based on, model parameters that couldn't be obtained experimentally were calculated using an angle-driven model. Hip contact force data collected across the group were used to approximate force that was realistic from hip-contact in the snatch. The torque-driven model was validated by matching the recorded performance with a simulation.</p><p dir="ltr">Following this, the torque generator activation timings were varied to maximise a score function to maximise weight lifted to a height such that the athlete would be able to snatch the barbell. The athlete's performance was compared to the optimised performance to highlight areas that contribute to performance in the snatch. Barbell trajectories, joint kinematics and torques were compared. It was found the double-knee bend technique had an impact on performance.</p>