Mathematical model to optimize goalkeepers' jumping

• Grant number: 12/03097-2
• Support Opportunities: Scholarships abroad - Research
• Start date: June 30, 2012
• End date: February 27, 2013
• Field of knowledge: Health Sciences - Physical Education
• Principal Investigator: Sergio Augusto Cunha
• Grantee: Sergio Augusto Cunha
• Host Investigator: Walter Herzog
• Host Institution: Faculdade de Educação Física (FEF). Universidade Estadual de Campinas (UNICAMP). Campinas , SP, Brazil
• Institution abroad: University of Calgary, Canada

Abstract

In soccer, the goalkeepers have very specific characteristics regarding their physical preparation, technique and tactics. The goalkeeper's movement, when he executes the defense, consists of three phases: the ready position, the first step and the jump. There the aim of this study is to optimize the movement strategy of a goalkeeper's defense movement by means of a mathematical model that includes subject-specific muscle properties. Specifically, we will optimize the first step phase that provides maximal jumping performance in a minimum of time. Ten youth goalkeepers will be assessed. They will all sign an informed consent form. From the determination of hip, knee and ankle angles that maximize the goalkeeper's jump power, the participants will perform the jump starting from ready position and executing the first step trying to achieve a ball launched to their right side. So the player has to perform a jump that is as high as possible and to land on a foam mattress. Some marker will be set strategically, in order to calculate flexion/extension angles of the hip, knee and ankle. The results will be used to position the goalkeeper's body relative to the position of maximal muscular power output identified by the mathematical model. To verify if the results of the mathematical models are compatible with the experimental situation will be compared the two jump types of each goalkeeper and to verify if there is an improvement of the resultant power when using the strategy identified by the model. (AU)