Core muscle endurance and balance as predictors of lateral ankle sprain in adolescent team-sport athletes: a prospective cohort study

Background Lateral ankle sprain is a common and recurrent injury among adolescent athletes, particularly in team sports that involve jumping, cutting, and single-leg landing. Identifying practical preseason predictors may help guide targeted injury-prevention strategies.Objective This prospective cohort study aimed to determine whether preseason measures of core muscle endurance, static balance, and dynamic balance could predict future lateral ankle sprain in adolescent male team-sport athletes.Design A prospective cohort study.Methods A total of 152 male adolescent athletes competing in soccer, volleyball, basketball, and handball were followed prospectively for 20 months. Baseline assessments included trunk flexor and extensor endurance, right and left side plank endurance, static balance, and dynamic balance in three directions (anterior, posteromedial, posterolateral) as well as a composite score. Lateral ankle sprain was defined as a non-contact inversion injury that caused time loss from training or competition. Variables with p < 0.20 in the univariate analyses were entered into a multivariable logistic regression model using forward stepwise (likelihood ratio) selection. Model performance was evaluated using odds ratios, Nagelkerke’s R2, Hosmer-Lemeshow goodness-of-fit, and receiver operating characteristic (ROC) analysis.Results During follow-up, 34 athletes (22.4%) sustained a lateral ankle sprain. In the multivariable model, two independent predictors were retained: trunk extensor endurance (OR = 0.989, 95% CI: 0.980–0.998, p = 0.020) and dynamic balance composite score (OR = 0.937, 95% CI: 0.901–0.975, p = 0.001). The model demonstrated good calibration (Hosmer-Lemeshow p = 0.616) and explained 22.4% of the variability in injury status (Nagelkerke R2 = 0.224). The combined model showed moderate discriminative ability (AUC = 0.751, 95% CI: 0.664–0.837, p < 0.001), with an optimal cutoff yielding 88.2% sensitivity and 55.1% specificity.Conclusion In adolescent team-sport athletes, lower trunk extensor endurance and poorer dynamic balance were associated with a higher likelihood of lateral ankle sprain. Assessment of these two simple field-based measures may aid preseason injury risk screening. However, the model should be validated in independent cohorts before clinical application.