Content area
Full Text
Aim. The aim of the present study was to compare linear kinematics and energy changes of the barbell, along with the angular kinematics of the leg movement during the snatch technique, between male adolescent and adult weightlifters.
Methods. Two S-VHS cameras operating at 60 fields per second recorded the heaviest lifts of 14 male adolescent and 9 adult top-level weightlifters under competitive conditions. The spatial co-ordinates of selected points on the body and the barbell were calculated using the direct linear transformation procedure. A low pass digital filter with 4 Hz cut-off frequency was used for the smoothing of raw co-ordinate data. The "t"-test for independent samples was used for the statistical treatment of data.
Results. The results revealed that there were no significant differences between the adolescent and the adult weightlifters in the majority of the kinematic variables. However, adolescent weightlifters extended their knees significantly slower (t^sub 21^=4.211, p<0.05) during the 1st pull and their ankles during the 2nd pull (t^sub 21^=2.440, p<0.05) than the adult weightlifters did. Moreover, the average relative power output was significantly greater for the adult weightlifters during both the 1st (t^sup 21^=2.303, p<0.05) and the snd pull (t^sub 21^=2.611, p<0.05).
Conclusion. These results indicate that the adolescent weightlifters were characterised by a high level of snatch technique and differentiated from the adults predominantly at the less powerful execution of the movement.
KEY WORDS: Biomechanics * Snatch technique * Three-dimensional kinematic analysis * Adolescence.
In weightlifting, the competition performances are controlled with strict rules and therefore great variations in lifting technique among weightlifters may not be expected. However, it can be suggested that among weightlifters of different level there might exist differences in the biomechanical characteristics of the snatch lift, which could explain the differences in the weightlifting performance level.1
The snatch technique requires the barbell to be lifted from the floor to a straight-arm overhead erect standing position in one continuous movement.2 The total movement can be divided into 6 phases (Figure 1): the 1st pull (A), the transition from the 1st to the 2nd pull (B), the 2nd pull (C), the turnover under the barbell (D), the catch phase (E) and the rising from the squat position (F). The lift of the barbell from the floor to...