The snatch is the most technical component of a weightlifting competition (Gourgoulis et al., 2000). The snatch technique requires the barbell to be lifted from the floor to a straight-arm overhead position in one continuous motion (Burdett, 1982; Gourgoulis et al., 2000). Many factors can influence the outcome of a snatch attempt. Therefore, whatever determines success is likely to be multifactorial in nature (Stone et al., 1998). The primary factors that affect the success of weightlifters in the snatch technique of weightlifting are explosive strength, flexibility, and as well as technique (Enoka, 1979; Garhammer, 1985; 1991; Gourgoulis et al., 2000; Isaka et al., 1996; Ikeda et al., 2012; Schilling et al., 2002; Stone et al., 1998).
There are currently many studies available in literature that examined the kinematics of the snatch technique in elite male (Baumann et al., 1988; Garhammer, 1985; Gourgoulis et al., 2000; 2002; Harbili, 2012; Isaka et al., 1996) and female weightlifters (Akkus, 2012; Gar hammer, 1991; Gourgoulis et al., 2002; Hoover et al., 2006; Ikeda et al., 2012). However, few studies have focused on the barbell energetics, its kinematics and the angular kinematics of the limb during the snatch in adolescent (Gourgoulis et al., 2004) and elite male junior weightlifters (Campos et al., 2006). Previously published data for snatch and clean pulls of adult weightlifters revealed that as the weight lifted increases, the duration of the pull also increases, but the maximum and average pull velocities, maximum barbell height, and power outputs decrease (Garhammer, 1985; 1993). Garhammer (2001) reported that a small decrease in weight, about 5%, could often increase power output substantially because of a considerably greater movement speed and shorter time interval for the completion of the lift. In addition, in a recent study, it was revealed that the vertical and horizontal kinematics of the barbell and body decreased at the pull phase of the snatch technique as the barbell load increased. The power output during the second pull increased although the work done did not change, whereas work and power output increased during the first pull depending on the increase in the barbell weight (Hadi et al., 2012). Gourgoulis et al. (2004) reported that adult male lifters are superior to adolescent lifters from the perspective of relative power output during the snatch lifting and that adolescent lifters are less skillful than adult lifters in the second pull phase, which is the power phase of the snatch technique. It was also reported that the barbell trajectories varied greatly in the snatch lifts of elite male junior lifters of different weight and that lifters belonging to heavier categories were more efficient, as they managed to have longer barbell propulsion trajectories (Campos et al., 2006).
The analysis of the snatch technique performed by adolescent lifters is extremely interesting due to the fact that the weightlifters are in initial phase of high performance (Campos et al., 2006). Therefore, determining the effects of the increased barbell load on the snatch technique in adolescent weightlifters is especially important to manipulate training in order to help them lift heavier loads. Thus, training programs specifically designed to improve the strength and technical competence of lifters at this age could lead to better preparation of the adolescents for not only their current but also adulthood performance. For this reason, during the snatch lift of junior lifters, it is possible that the barbell weight will affect the linear movement of the barbell and the angular kinematics of joints. The objective of the study was to compare the linear kinematics of the barbell and the angular kinematics of the lower limb during the snatch lifts of two different barbell weights in elite male junior weightlifters.
Nine elite male adolescent weightlifters at national team level (age: 18.89 [+ or -] 0.78 years, height: 1.70 [+ or -] 0.07 m; body mass: 73.76 [+ or -] 16.77 kg, training age: 5.46 [+ or -] 0.78 years) participated in the study (Table 1).
All weightlifters were members of the national team and seven of them participated in the 36th Men's World Junior Championships and European Junior Championships in 2010. This study was conducted in accordance with the guidelines set forth by the Institutional Review Board of Selcuk University. All participants signed informed consent forms approved by the University Ethics Committee.
The three snatch lifts performed under competitive conditions by national adolescent weightlifters who were preparing for European Junior Championship were analyzed to determine the linear kinematics of the barbell and the angular kinematics of the lower limb. Each weightlifter recovered for 1-min between snatch attempts. The heaviest two successful snatch lifts of the three lift attempts of each subject were chosen for kinematic analysis.