Ferreira, Hugo AlexandreDelgado, Pedro Alexandre Sequeira2023-03-2120232022http://hdl.handle.net/10451/56728Tese de mestrado integrado, Engenharia Biomédica e Biofísica (Engenharia Clínica e Instrumentação Médica), 2022, Universidade de Lisboa, Faculdade de CiênciasFootball as the most played sport in the world, should be the greatest force in the development of sport and the science involved in it. However, football has always possessed an "aura" of simplicity. In spite of that, the clubs that have focused on this, have seen their efforts rewarded, both in trophies and in monetary terms. In this study, with the help of two clubs from the Portuguese Football League, a biomechanical analysis of the performance of direct Free Kicks by players of different ages and in different zones of the field was performed. The kinematic and electromyographic parameters of Free Kicks performed by eight players from the under 23 and B teams of one of the most well regarded Portuguese football team, were evaluated. These kinematic parameters consisted of the angle of the supporting leg, the last stride length and the distances covered, the maximum velocity and the average speed of the movement of these joints. In the electromyography we analyzed three leg muscles. Our results revealed that the angle of the supporting leg seems linked to impact absorption of the movement performed. We also concluded that the greater the distance traveled by the foot, and of the last stride, the greater the ball speed. These parameters also seem to be linked with the body rotation. It was also observed that the medial gastrocnemius is activated earlier and longer than the quadriceps muscles, in all pitch zones. Free Kicks from greater distances show greater muscle activation than Free Kicks from nearest zones, while in laterality, no major changes were observed. These findings reinforce that the study of this field can still evolve a lot, and that a greater investment by sports teams and researchers in the development and expansion of knowledge in sports performance analysis can offer advantages that, in these competitions, are often invaluable.engAnálise de PerformanceBiomecânicaEletromiografiaCiência do DesportoFutebolTeses de mestrado - 2023master thesis203507800