Efeito da idade relativa sobre a assimetria técnica funcional de futebolistas da categoria sub 17

Abstract

Studies show that soccer athletes who are born in the first months of the year can obtain physical advantages over others due to the relative age effect. However, it is important to verify if the relative age effect also influences in functional asymmetry of lower limbs in young soccer players, a fundamental factor to improve technical and tactical performance. Thus, the aim of the present study was to verify the relative age effect on the functional asymmetry of lower limbs of soccer players in the under 17 category. For this, all the games of the four semifinalist teams of the 2019 FIFA U- 17 Soccer World Cup were analysed (Brazil, France, Mexico and the Netherlands). Longomatch platform was used to perform the video analysis. To analyze functional asymmetry, the "System of Assessment of Functional Asymmetry of the Lower Limbs in Football" was used, an instrument that assesses the index of use of both lower limbs during the game. The website Transfermarket was used to obtain information about the birth date, dominant foot and game position of the players. The results showed an over representation of players born at the beginning of the year in the division in tertiles, quartiles and semesters. There was no relative age effect on the positional status of players, but there was an overrepresentation of players born in the 1st tertile in defenders, full-backs and forwards. There was no significant difference between birth tertiles regarding the functional asymmetry index and the assertiveness of technical actions with both feet. Thus, it can be concluded that there was a relative age effect in the present sample, but the birth tertile did not influence the index of use of both feet to play soccer.