The acute fatigue effects of Small-Sided Games on lower limb strength, inter-limb asymmetry and landing technique in young Under-15 female soccer players

Background. The increase in young female soccer players requires understanding the adaptations determined by sport-specific exercises both to enable improvements in sports performance and to reduce injury risk in women’s soccer. Objectives. This study aimed to analyze the acute effects of Small-Sided Games (SSG) on landing technique control, lower limb strength and lower limb functional asymmetry in Under-15 female soccer players. Materials and Methods. A total of 18 young female soccer players (age:14.04 ± 0.26 years, weight: 51.56 ± 2.9 kg; height: 146.9 ± 3.22 cm) randomly performed hop test, Landing Error Scoring System assessment and vertical jump at the end of warm-up (pre-fatigue condition) and post SSG (3vs3, 4 × 4 min on field 24,5m × 24,5 m, post-fatigue condition). The inter-limb asymmetry value was calculated by comparing the two hop tests (left and right) using the formula: (highest performing limb – lowest performing limb/highest performing limb)×100. Results. The hop test and vertical jump results in the pre vs. post-SSG comparing showed a significant performance decrease (p < 0.001, ES:1.43 and 1.43, respectively). The inter-limb asymmetry value significantly increased (p < 0.001, ES:1.18) from 9.07±2.67% to 13.42±7.49%. The landing control value has undergone a substantial decrease from 5.72 ± 0.67 to 7.83 ± 0.86 (p < 0.001, ES:1.29). Conclusions. The findings indicate that high-intensity soccer drills have an impact on the landing control quality, decrease explosive strength performance, and increase inter-limb asymmetry value. Soccer-specific exercises must be carefully modulated within the training session.