Performance analysis of the taekwondo pushing kick (Miluh-chagi) in adolescent black belts

Taekwondo, a Korean martial art and Olympic sport since the Sydney 2000 Olympic Games, emphasizes kicking skills for optimal performance. The pushing kick (Miluh-chagi) targets the opponent's midsection or head and follows a linear path. It is a standard push kick in Taekwondo and can score points like other techniques. This study aimed to analyse the technical performance indicators during the execution of the pushing kick (lifecycles of ten kicks) by Taekwondo athletes, using an observational tool: the Observation System for Technical Performance Indicators-Chagi (OSTIP-C).

This study used observational methods to assess motor competence in adolescent athletes during a pushing kick, analysing a total of 12 athletes (5 females, 7 males). The reliability and precision of scores were assessed across 120 kicking trials, consisting of ten execution lifecycles performed by each of the twelve taekwondo black belt athletes in the sample. Precision was measured with the coefficient of variation, and evaluator reliability with the intraclass correlation coefficient. Student's t-test compared maximum variable values, while Spearman's rho analyzed correlations. In the same line, Linear Mixed-Effects Model were used to analyze data where observations are not independent (e.g., repeated measures of the lifecycle of the Miluh-chagi Taekwondo kick). It decomposes variance into fixed effects (lifecycle of the kick) and random intercept (performance score by subjects). The level of significance was established on p < 0.05.

The sample data were reliable, with strong intra- and inter-rater agreement. Significant differences appeared in foot take-off, knee up, and start leg flexion (p < 0.05; Cohen's d = 0.8). Conduct and aggregate criteria showed small to moderate negative correlations (r = 0.181; p < 0.05 and r = 0.396; p < 0.01). On the other hand, there was a perfect correlation between support leg position and attacking leg foot position.

The results show significant differences in the foot take-off, knee-up, and start-leg flexion phases, highlighting these early moments of the movement as the most variable and technically demanding. These phases appear to be critical for the coordination and efficiency of the kicking action.