Biomechanical analysis of the classic snatch barbell technique in female weightlifters of different levels of training

Background and Study Aim. The study is devoted to the biomechanical analysis of the technique of performing the competitive exercise "classic snatch" in female weightlifters of different sports qualification groups of the second group of weight categories (58, 63, 69 kg). Particular attention is paid to the spatio-temporal characteristics of movements that determine the effectiveness of the lift and reflect the level of technical training. The purpose of the study is to conduct a comparative biomechanical analysis of changes in speed indicators and spatial characteristics of the competitive exercise of the classic snatch in female weightlifters at different stages of long-term training. Material and methods. The study involved 52 female athletes aged 13 to 21 years, divided into three groups: the first group included 22 athletes at the preliminary basic training stage (average age 13 years); the second group included 17 athletes at the specialized basic training stage (17 years); the third group included 13 athletes at the stage of maximum realization of individual capabilities (21–22 years). Biomechanical analysis was performed using Dartfish software by frame-by-frame analysis of the technique of performing a snatch with a load of 60% of the maximum weight. The angles of the torso, angles in the hip and knee joints, as well as the duration of the seven phases of lifting the barbell were determined: interaction with the barbell, preliminary acceleration, cushioning, final acceleration, unsupported and supported squat, standing up and fixation. Results. The obtained data showed a clear tendency to improve the technique with the growth of sports qualification. The athletes of the third group had a significantly shorter time to complete all phases of the snatch (p<0,001), which indicates a higher efficiency of motor actions. In particular, the duration of the final acceleration decreased from 1.102±0.027 s in the first group to 0,893±0,027 s in the third (t1,3=5,47; p<0,001). Analysis of angular characteristics showed a progressive increase in the optimal positions of the torso and joints: the angle in the hip joint in the amortization phase increased from 93,4±5,57° (first group) to 136,9±5,21° (third group; p<0,001), and the angle in the knee joint in the unsupported squat phase decreased from 125,6±5,69° to 75,4±5,69°, which indicates an improvement in the depth of the squat and the explosiveness of the movement. In the rising and fixation phases, a more stable vertical position of the torso was noted in athletes of the second and third groups compared to the first, which confirms the adaptation of the neuromuscular system to competitive loads. Conclusions. The results of the study indicate that the gradual improvement of the classic snatch technique is accompanied by a gradual improvement in the spatio-temporal characteristics and angular parameters of the joints. The use of video analysis in the Dartfish program revealed key differences between the groups, allowing for targeted correction of technical training, identification of phase "weak points" and selection of specialized underwater exercises depending on the individual profile of female athletes.