Abstract

Various dynamic kinematic, kinetic and electromyographic characteristics of the olympic weightlifting technique of the snatch and clean jerk from submaximal to maximal loads were investigated in seven weightlifters of Finnish national level (ELI group) and in six weightlifters of the district level (DIS group). Greater (p < .05 - .01) maximal relative ground reaction forces were recorded in both groups at submaximal (70, 80, 90) loads than at maximal (100) loads during first and third pulls of the snatch and clean. The relative forces during the concentric phase of the jerk decreased (p < .05-.001) in the two groups when the load of the barbell increased. During the first pull of the lifts the ELI group produced greater (p<.05) reaction forces at all loads than the DIS group. During the third pulls of both lifts the velocities of the barbell decreased significantly (p<.05) in the two groups when the load of the barbell increased. The average durations of the drop under the bar phases in the snatch, clean and jerk were in both groups significantly (p<.05-.01) longer at 100 loads than at 70 loads. In the jerk, in addition the durations of this phase were shorter (p<.05-.01) in the ELI group than in the DIS group. The maximal relative lifting heights of the barbell in the two lifts decreased (p < .05 - .001) in the two groups when the load increased. No group differences were noted in the relative IEMG values of the different lifting phases of the snatch and clean jerk at 70 or 100 loads. The present data indicated that the biomechanical structure in the olympic lifts was related to the load of the barbell lifted. This was true in the elite weightlifters as well as in the weightlifters at the lower performance level. Verf.-Referat