Análise biomecânica da estirada aérea do guarda-redes de futebol sénior: comparação entre a técnica de defesa com a mão inferior e a técnica de defesa com a mão superior

Abstract

In Football there´s a player who assumes particular features which distinguishes him amongst the other players: the Goalkeeper. In the multiplicity of actions to which a player is submitted, we recognize that the aerial save is a decisive action, namely when only one hand is used to defend the ball, through the defensive technique with the bottom hand and the defensive technique with the top hand. Thus, this study highlighted, as main purpose, the biomechanics analysis and comparison of the efficacy between the bottom hand technique and the top hand technique in aerial saves of Football professional goalkeepers also considering, as well, the preferences in terms of laterality (preferred side and the non-preferred side), and the performance of the First League goalkeepers and the Professional Portuguese Second League of Football.The sample consisted of twelve goalkeepers, with an average of 27.9 (±5.5) years of age and 10.1 (±5.3) years of experience in the professional Football. The experimental procedures took place in the Biomechanics Lab of Porto, where force platforms were used as well as a system of kinematic motion capture. The goalkeepers were assessed in their aerial saves performed using either the bottom hand and the top hand technique towards a stationary ball, placed to a lateral distance of 2.30 m, to a height from the ground of 1.90 m and to a distance from the goal line of 0.60 m.The results achieved did not showed signified differences between the two techniques, nonetheless the slight differences found allow a greater efficacy to the bottom hand technique. To what laterality preference is concerned, it was perceptible that the goalkeepers showed a better proficiency when they performed an aerial save towards their preferred side. According to the variables that were analysed, it was, also patent that the Goalkeepers of the First League, showed a better efficacy when compared to the ones of the Second league.