Changes in Bar Path Kinematics and Kinetics Through Use of Summary Feedback in Power Snatch Training

Abstract

PURPOSE: The purpose of this study was to investigate the direction and magnitude of kinematic changes in bar path and kinetic variable changes in the power snatch (PS) after four weeks of supervised training and the use of summary feedback. METHODS: 24 collegiate football players who had a minimum of 18 months of prior experience in the PS participated as subjects in this study. The subjects were pre-tested for their one repetition maximum (1RM), pair matched, and randomly separated into a feedback vs. control group. The feedback group was provided with visual and verbal cues during power snatch training sessions, which took place three times per week for four weeks. Variables measured during data collection include pre and post peak force, peak power and several bar path kinematic variables through videography at 50, 70, and 90% of the subjects' pre-1RM. RESULTS: Peak force was improved at 50% of 1RM from 567 ± 202 to 769 ± 230 N, at 70% from 725 ± 186 to 890 ± 199 N and at 90% from 822 ± 197 to 1008 ± 201 N. Peak power was increased at 50% of 1RM from 2061 ± 562 to 2538 ± 498 watts, at 70% from 2321 ± 743 to 2754 ± 629 watts, and at 90% from 2076 ± 437 to 2491 ± 526 watts. Variables with respect to bar path kinematics were improved significantly. No improvements in kinetics or kinematics were noted in the control group.Figure: Caption not provided.CONCLUSIONS: These results indicate that both kinematic and kinetic variables improve through training and feedback. It is possible that persons beginning the PS exercise or coaches who provide instruction on the power snatch to beginning lifters should focus on proper bar path during the movement and the manner in which feedback is provided. This may result in force and power output to develop as technique improves even in more experienced lifters.