Resumen de A Preliminary Investigation of the Biomechanical and Perceptual Influence of Chain Resistance on the Performance of the Snatch
Cheryl A. Coker, Joseph M. Berning, Doug L. Briggs
Coker, C.A., J.M. Berning. and D.L. Briggs. A preliminary investigation of the biomechanical and perceptual influence of chain resistance on the performance of the snatch. J. Strength Cond. Res. 20(4):887-891. 2006.-The purpose of this study was to determine whether the addition of chains to a barbell during the performance of the snatch would invoke differences in execution compared with lifting a conventional barbell without chains. Additionally, subjects were asked whether they perceived that the addition of chains had effects on their performance, and, if so, what those effects were. Four male and 3 female competitive weightlifters who regularly used chains as part of their training programs participated in the study. They were compared lifting 80% of 1 repetition maximum (1RM) using conventional barbells with 80% of 1RM, 5% of which was accounted for by chains. The same procedure was used with 85% of 1RM. Variables examined included maximum vertical displacement of the bar, maximum bar velocity, rate of force production of the bar, and vertical ground reaction forces for the first pull, unweighting, and second pull phases of the lift. Results indicated that there were no statistically significant differences between the chain vs. no-chain conditions at either 80% or 85% of 1RM. In contrast, 100% of the subjects stated that they perceived that the addition of chains made them work harder during the snatch. They suggested that the chains forced them to pull harder throughout the lift and that oscillation of the chains required their shoulders, abdominals, and back to work harder to stabilize the bar in the catch phase. Although statistical results indicate that chains have no influence on the snatch technique, chains may have a psychological impact and possibly invoke a physiological training response by increasing strength of muscles required to stabilize the bar during the catch phase if used over time.
