(15) A COMPARISON OF BARBELL TRAJECTORIES BETWEEN SUCCESSFUL AND UNSUCCESSFUL POWER CLEAN ATTEMPTS

Background: The trajectory of the barbell during the performance of weightlifting movements is one of the most common variables analyzed because of its association with weightlifting performance. However, it remains unknown whether the patterns of the barbell trajectory during the power clean are associated with successful and unsuccessful attempts.

Purpose: To determine the relationship between barbell trajectory and successful and unsuccessful power clean performance.

Methods: Twelve strength-power athletes (10 males; 2 females), with the ability to power clean ≥1.0 times their body mass were recruited for this study. All subjects completed a standardized one repetition maximum (1RM) power clean test that began with the performance of five repetitions with 30% and 50% of the subjects estimated 1RM, and three repetitions performed with 70% of the estimated 1RM, followed by single repetitions performed with 80% and 90% of the estimated 1RM. Following these warm-up sets, subjects performed a maximum of five 1RM attempts, each separated by three-minutes of rest. Barbell trajectory data from the heaviest successful lift and the heaviest unsuccessful lift were extracted for further analyses. Barbell trajectories were tracked using a three-dimensional motion capture system which allowed for the vertical and horizontal displacement of the center of the barbell to be calculated. Bivariate functional principal component (bfPC) analyses were performed to extract two bfPCs that accounted for most of the variances in barbell trajectory data (85%), with bfPC scores extracted for statistical analysis. Statistical analyses included dependent t-tests to examine differences in bfPC scores between successful and unsuccessful power clean lifts.

Results: There were significant differences in bfPC scores from the first bfPC (p < 0.001) and the second bfPC (p = 0.008) between successful and unsuccessful power clean lifts (Figure 1). The first bfPC extracted from the barbell trajectory data captured variations related to barbell height during the second pull and the turnover phase of the power clean (Figure 1), with unsuccessful lifts likely to display a lower barbell height during these phases compared to successful lifts. Similarly, the second bfPC captured variations related to barbell height during the transition phase of the power clean (Figure 1), with unsuccessful lifts likely to display a lower barbell height during this phase compared to successful lifts.

Conclusions: Lower barbell heights during the transition, second pull and the turnover phases were associated with unsuccessful power clean performance. PRACTICAL APPLICATION: It is recommended that coaches and athletes emphasize maintaining a high vertical barbell displacement during the transition phase, likely resulting in higher barbell heights during the second pull and turnover phases. This approach may increase the likelihood of successful power clean performance.


Acknowledgements: None