Asimetrías en la fuerza y la potencia de las extremidades inferiores en la selección chilena de balonmano categoría junior

Introduction. Bilateral asymmetry is defined as the difference between the right and left sides, or between the dominant and non-dominant limbs. In sports, the specific demands of training and competition often favor the development of one limb over the other, potentially leading to muscle imbalances that increase the risk of injury and reduce performance. Objective: The purpose of this study was to determine lower-limb asymmetry levels using single-leg jump tests, comparing the dominant limb with its contralateral in pre-throw jumps among Chilean junior national handball players. Methods: A cross-sectional study was conducted with 16 male athletes (mean age: 19.9 ± 1.6 years; mean body mass: 84.3 ± 8.3 kg; mean height: 183.8 ± 5.3 cm). Four single-leg jump tests were performed: squat jump (SJ), countermovement jump (CMJ), drop jump (DJ), and Abalakov jump (ABK). Eleven players demonstrated left-leg dominance, and five right-leg dominance. Results: No statistically significant differences were observed between limbs in jump height, strength, or power. Relative asymmetry values ranged from 3% to 17% in both groups. Discussion: Greater asymmetries were found in right-dominant athletes (>10%) compared with left-dominant athletes (<8%), without significant effects on performance. However, monitoring these differences remains important due to their association with injury risk. Conclusions: Limb dominance did not guarantee superior performance over the contralateral limb. Observed inter-limb differences were mild and non-significant, suggesting that natural asymmetries below 10% may be advantageous in high-performance sports by minimizing injury risk and optimizing athletic performance.