A Study on the Lower Limb Biomechanical Characteristics of Elite Weightlifter Li Fabin during the Snatch Phase—Based on Anybody Simulation

Objectives: This study uses the Anybody simulation software to analyze the dynamic data of elite weightlifter Li Fabin during competition, focusing on the biomechanical characteristics during the critical snatch phase. The research aims to provide theoretical support for training, evaluating, and di-agnosing technical movements during this phase of weightlifting. Methods: High-speed cameras were placed on both sides of the weightlifting platform to capture video footage of Li Fabin performing a 143 kg snatch at the 2020 National Weightlifting Championship. The SIMI Motion 10.0 motion analysis system was used to mark 42 skeletal features manually. The data was imported into the Anybody simulation, and various parameters such as height, weight, and barbell weight were defined. Results: During the snatch phase, the vertical ground reaction force (VGRF) increased continuously in the sag-ittal axis direction. The peak VGRF reached approximately 3332.0N, equivalent to 5.5 times the body weight, at 63% of the force generation phase. The athlete’s lower limbs reached their peak forces simultaneously, with the hip, knee, and ankle forces being notable. Muscle strength imbalances between the two legs were observed, with the left leg having lower strength in specific muscle groups. Conclusions: 1) Elite athletes can generate significant ground reaction forces, emphasizing the importance of lower limb extensor training while considering biomechanical principles. 2) Approaching the barbell during the knee extension and lifting phase increases the vertical ground reaction force, highlighting the need for knee extensor training and knee joint stability. 3) The timing of peak muscle forces in certain muscle groups can contribute to improved hip extension power. Training for high-weight hip extensor strength should focus on activating specific muscle groups. Muscle strength imbalances between the left and right lower limbs may impact snatch success and should be addressed by coaches and athletes to maintain proper barbell balance.