Paper Title
PHYSICAL FUNCTION CHARACTERISTICS OF YOUTH CHINESE ELITE SOCCER PLAYERS

Abstract
PURPOSE: The quality of physical functions directly impacts soccer players’ performance in matches. Nonetheless, there is a paucity of study on physical function among soccer players, particularly among adolescent players.To develop sports performance,this study aimed to assess the physical functions of youth Chinese elite male soccer players using medical check-up, focusing on the trunk and lower limbs. METHODS: A total of 30 male elite soccer players at a national tournament level participated in the study. Physical function tests of medical check-ups were performed among all the participants aged 13-17 years. A questionnaire survey asked for basic parameters includingage, height, weight, years of soccer experience, training hours of per day, training days of per week. The physical function tests comprising of general joint laxity test, straight leg raising (SLR), Passive Ely’s test (PET), single leg stance, trunk strength, range of motion of the hip and trunk joint, were performed. Independent-samples t-test, pair-samples t-test, Mann-Whitney U test and Wilcoxon’s rank-sum test were used for data analysis. RESULTS: All the participants presented a mean age of 15.8 ± 0.2 years, with a mean height of 179.0 ± 1.1 cm, and a mean weight of 67.9 ± 1.5 kg. The participants showed significant differences in SLR betweenthe leftand right legs (left vs right: 113.8± 9.8° vs 108.0± 8.6°, p = 0.001) and PETbetweenthe leftand right legs(left vs right: 30.61 ± 5.33° vs 34.45 ± 6.05°, p < 0.001). In terms of ankle joint flexion, there was a significant difference in the minimum flexion between the left and right feet(left vs right: 60.2 ± 5.3° vs 58.6± 5.2°, p = 0.007).In terms of hip abduction, there was a significant difference between the left and right sides (left vs right: 167.2± 13.3° vs 161.5 ± 10.6°, p = 0.023). CONCLUSIONS: The youth Chinese elite soccer playersshowed interlimb imbalances in hamstring flexibility, ankle joint range of motion, and hip joint range of motion. To improve sports performance and to avoid injury related to soccer, coaches, members of the entourage, and physiotherapists should focus on interlimb asymmetryin physical function.