Effects of a high-intensity interval training program on physical and physiological parameters in adolescent female field hockey players

High-intensity interval training (HIIT) is frequently used in the field of sports to promote physical fitness through exercises that include speed, agility, cardiorespiratory capacity, maximum strength, explosive power, and flexibility. In this study, the effect of a HIIT program on physical and physiological parameters in adolescent female field hockey players was examined. A parallel-group randomized controlled trial (RCT) with a pre-test–post-test design was conducted. Participants were randomly divided into two groups: the control group (CG; n = 12), who continued regular field hockey training, and the experimental group (EG; n = 12), who received complementary body-weight-based HIIT. The intervention lasted for 1 h, 3 days a week for 8 weeks. Physical and motoric parameters (static balance, flexibility, standing long jump, reaction time, and VO 2 max) were evaluated. Pre- and post-intervention comparisons were analyzed using a 2 × 2 Repeated Measures Mixed ANOVA. Statistical significance was set at p < .05, and Partial Eta Squared was used to evaluate effect sizes. The mixed ANOVA results showed a significant Group $\times$ Time interaction with large effect sizes for VO 2 max ( p < .001, η p 2 = 0.488) and reaction time ( p = .041, η p 2 = 0.176) in favor of the EG. Conversely, no significant interaction effects were found for static balance, standing long jump, and flexibility, indicating that HIIT did not provide additional benefits for these parameters over standard training. Additionally, a significant main effect of time showed a decrease in flexibility for both groups. In conclusion, the eight-week HIIT program is a highly effective method for significantly improving aerobic capacity (VO 2 max) and reaction time in adolescent female field hockey players. However, standard hockey training is equally sufficient for maintaining balance and jumping performance, while specific routines are required to prevent flexibility loss. ClinicalTrials.gov NCT07433348. Date of trial registration 20.02.2026. The trial was retrospectively registered, after participant enrollment had been completed.