Frontal Plane Knee Projection Angle and Functional Performance in Adolescent Female Volleyball Players

This observational study aims to examine the relationship between frontal plane knee projection angle, dynamic balance, agility performance, and ankle dorsiflexion mobility in adolescent female volleyball players. Frontal plane knee projection angle will be assessed during a single-leg squat using two-dimensional video analysis. Dynamic balance will be evaluated with the Lower Quarter Y-Balance Test, agility with the T-Test, and ankle dorsiflexion mobility with the Weight-Bearing Lunge Test. All measurements will be completed in a single session under standardized field conditions, and no intervention or experimental treatment will be applied. By investigating how frontal plane knee alignment is associated with functional performance measures, this study may help improve the understanding of biomechanical factors related to movement quality and injury risk in adolescent female volleyball players.

Inclusion Criteria: * Being female and between 10 and 19 years of age * Participating in regular volleyball training at least 3 days per week * Having reached menarche Exclusion Criteria: * Having sustained a lower extremity injury within the previous 6 months * Having a history of lower extremity surgery * Using medication that could affect balance, attention, or physical performance * Having a neurological, orthopedic, or systemic condition that could affect performance