The role of core stability training in improving balance and poomsae technique quality in taekwondo poomsae athletes with neuromuscular control deficits with trunk involvement: a randomized controlled trial

Poomsae taekwondo athletes require high levels of static and dynamic balance and trunk core muscle endurance due to complex movement patterns, rapid directional changes, and explosive kicks. Neuromuscular control deficits with trunk involvement can reduce performance and increase injury risk. This study examined the effects of core stability training on balance, trunk endurance, and sport-specific performance in poomsae athletes with trunk involvement. Twenty-nine male athletes (18–25 years) from Alborz Province were purposively sampled and randomly assigned to an experimental group ( n = 14) or control group ( n = 15). The experimental group completed 8 weeks of core stability training, three sessions per week (45–60 min), while controls maintained regular training. Static and dynamic balance were measured using the Stork Balance Test and Star Excursion Balance Test. Trunk endurance was evaluated with McGill’s tests: 60° trunk flexion, Biering–Sorensen and side bridges. Sport-specific performance was assessed via Ap Chagi, Yop Chagi, and Dollyo Chagi using video analysis scored by five certified judges. Significance was set at P < 0.05. Core stability training significantly improved the measured outcomes in the experimental group. Significant Time × Group interaction effects were observed for static and dynamic balance, trunk muscle endurance (abdominal, lateral, and back extensors), and poomsae performance, with large effect sizes (ηp² = 0.38–0.84; all P < 0.001). After Bonferroni correction, significant between-group differences at post-test were observed only for 60° trunk flexion, left-side bridge, and overall trunk muscle endurance ( P < 0.005). No significant between-group differences were observed for dynamic balance, static balance, Sorenson, right-side bridge, Ap Chagi, Yop Chagi, or Dollyo Chagi. Targeted core stability training significantly improved balance and trunk muscle endurance in poomsae athletes, with additional improvements observed in selected sport-specific performance measures. These findings suggest that incorporating core stability exercises into poomsae training programs may enhance physical preparedness and selected aspects of technical performance. Further research is warranted to determine whether these improvements translate into meaningful competitive performance benefits and reduced injury risk. IRCT20251216068361N1 (date of registration on December 20, 2025). registered in the Iranian Registry of Clinical Trials.