The effect of core stability training on improving balance moderated by strength in early age karate students

Background and Study Aim. Core stability training is commonly used in youth martial arts practice to support postural control. Different training approaches and individual strength levels may influence balance outcomes in young karate athletes. Despite the application of various training methods, their relative effectiveness in improving balance remains a matter of practical interest. The purpose of this study was to investigate the effect of core stability training on balance improvement in young karateka. Materials and Methods. This 2×2 factorial experiment included 40 male karateka (aged 6–8 years) selected through purposive sampling and grouped using matched-subject ordinal pairing. The research instruments consisted of the plank test and the star excursion balance test. Data analysis techniques were Two-Way ANOVA, Tukey’s post hoc test (p < 0.05), and effect size calculation (partial eta squared) using SPSS version 23. Results. There was a significant effect of the training method (core stability vs. control) (p = 0.000; ηp² = 0.707). There was a significant effect of core muscle strength (high vs. low) (p = 0.000; ηp² = 0.730). There was a significant interaction between the training method (core stability vs. control) and core muscle strength (high vs. low) (p = 0.009; ηp² = 0.174). Conclusions. The effectiveness of training in improving balance is not determined only by a single training method but is also strongly moderated by core muscle strength. Although both the core stability training method and core muscle strength factors have a moderate-to-high effect, the presence of a substantial interaction indicates that each karateka’s response is different. Identifying core muscle strength in young karateka is critical for achieving optimal balance.