TY - JOUR T1 - Explosive lower-limb strength predicts serve performance in competitive junior tennis players AU - Yücelsoy, Büşra AU - Şar, Halit AU - Acar, Şeyma Tuba AU - Ölmez, Cengiz PY - 2026 DA - May Y2 - 2026 DO - 10.31459/turkjkin.1859720 JF - Turkish Journal of Kinesiology JO - Turk J Kinesiol PB - Nurtekin ERKMEN WT - DergiPark SN - 2459-0134 SP - 164 EP - 171 VL - 12 IS - 2 LA - en AB - Serve velocity is a key performance determinant in tennis and relies on effective kinetic-kinematic energy transfer initiated by the lower limbs. While previous research has predominantly emphasized upper-extremity contributions, the neuromuscular characteristics of the lower limbs, particularly during the loading phase of the serve, remain insufficiently examined. Seventeen elite junior male tennis players participated in this study. Serve velocity was measured using a radar gun, while lower-limb neuromuscular performance was assessed via isokinetic knee and hip flexion–extension torque testing at angular velocities of 60°, 180°, and 240°·s⁻¹. Countermovement jump (CMJ) height was evaluated as a functional indicator of rapid force production capacity. Pearson correlation and multiple linear regression analyses were conducted to identify predictors of serve performance. Serve velocity was significantly associated with isokinetic torque outputs of the knee and hip joints across multiple angular velocities, as well as with CMJ height (p < 0.05). Greater knee flexion-extension and hip flexion-extension torque capacities were consistently related to higher serve velocities, and CMJ performance demonstrated a strong positive association with serve velocity. 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