The Biomechanical differences in maximum snatch weight between elite and sub-elite weightlifters: A one-dimensional statistical parameter mapping study

Background: Current research primarily relies on discrete data collected at specific time points to analyze the weightlifting process, often overlooking the impact of continuous temporal changes on athletic performance. Purpose: This study aimed to quantitatively analyze the one-dimensional kinematic patterns of maximum snatch weight actions in elite and sub-elite weightlifters using statistical parameter mapping (SPM). It explores kinematic differences in snatch actions between elite and sub-elite weightlifters, which assists in summarizing the technical characteristics of elite athletes. Methods: Two cameras recorded three successful maximum snatch attempts of 10 elite and 10 sub-elite weightlifters at the World Weightlifting Championships and Chinese Olympic selection competitions. Simi Motion 10.2 was used for kinematic analysis. SPM was employed for comparative analysis of snatch kinematics among different levels of weightlifters, and independent sample t-tests were used for phase duration proportions. Results: Elite weightlifters showed significant advantages in multiple movement phases: smaller knee joint angles in M1 phase (p < 0.001, 35.82%–78.45%) and M3 phases (p = 0.047, 17.47%–24.74%; p = 0.036, 30.92%–49.38%; p = 0.040, 50.93%–65.85%); lower vertical body center of gravity (COG) height in M1 phase (p = 0.019, 0.00%–51.08%), M3 phase (p = 0.046, 48.27%–100.00%), and M5 phase (p = 0.045, 38.49%–59.54%); closer displacement between barbell COG and body COG in M1 phase (p = 0.006, 0%–38.18%; p = 0.048, 43.91%–48.94%) and M2 phase (p = 0.026, 0%–100%); greater barbell acceleration in M5 phase (p < 0.001, 0%–94.61%); and slower barbell descent speed in M6 phase (p = 0.001, 0%–30.58%; p = 0.046, 44.57%–51.37%; p = 0.048, 67.16%–72.41%). Moreover, elite weightlifters exhibited significantly higher phase duration proportions in M1 phase (p = 0.034, d = 1.03) than sub-elite weightlifters. Conclusion: Elite weightlifters demonstrated longer distance and time exerting work on the barbell in M1 phase, less energy consumption in barbell ascent in M2 phase, and greater upward power gain for the barbell in M1 and M3 phases. They showed faster squat-to-barbell catching speed in M4 phase and excellent braking and precise squat-to-barbell catching capabilities in M5 and M6 phases.