AUTHOR=Hidayat Rahmat , Jin Xianzhi , Dou Chengji , Yang Benyao 
  
TITLE=Movement efficiency in taekwondo side kick (Yop Chagi): a kinematic comparison between novice and experienced practitioners
  
JOURNAL=Frontiers in Physiology
  
VOLUME=Volume 16 - 2025
  
YEAR=2026
  
URL=https://www.frontiersin.org/journals/physiology/articles/10.3389/fphys.2025.1708748
  
DOI=10.3389/fphys.2025.1708748
  
ISSN=1664-042X
  
ABSTRACT=BackgroundThis study aimed to kinematically compare the Yop Chagi execution between novice and experienced university Taekwondo practitioners, focusing on movement efficiency.MethodsForty university students were allocated into two groups: Novice (n = 20; ≤6 months experience) and Experienced (n = 20; ≥3 years of competitive experience). Participants performed maximal effort side kicks targeting a pad at trochanter height. Movement was captured using two high-speed cameras (120 Hz). Kinematic variables included hip and knee joint angles at peak flexion/extension, peak angular velocities, linear velocity of the foot, and total kick execution time. Between-group differences were analysed using independent t-tests or Mann-Whitney U tests, with effect sizes (Cohen’s d) reported.ResultsThe experienced group demonstrated significantly larger hip abduction and knee flexion angles during the chamber phase (p < 0.01, d > 0.8), and greater knee extension at the point of impact (p < 0.01, d = 1.2) compared to novices. The experienced group also exhibited superior performance in peak hip and knee angular velocities (p < 0.01, d > 1.5), resulting in a 28% higher peak linear velocity of the foot (p < 0.001, d = 2.1). Furthermore, the total execution time was significantly shorter for the experienced group (p < 0.01, d = 1.4).ConclusionExperienced practitioners execute the Yop Chagi with a more efficient kinematic pattern, characterized by a larger range of motion, faster segmental velocities, and reduced execution time. These findings suggest that long-term training optimizes the proximal-to-distal kinematic sequence, enhancing kick performance.