Rendimiento técnico-táctico del portero de fútbol

Abstract

The aim of this series of studies that constitute the present thesis was to analyse which goalkeeper performance indicators had more presence in a determined training method such as small-sided games (SSG). Study 1: The main aim of the first study of the present thesis was to design and validate an observational instrument for analysing the technical-tactical performance of the goalkeeper both in the offensive and defensive phase. The validity and reliability processes were carried out by 12 experts. After carrying out a quantitative and qualitative evaluation by them and testing the inter- and intra-observer reliability of the analysis of the different variables used, it can be determined that it is a valid and reliable instrument to measure the technical and tactical behaviour of the goalkeeper in football, both in attack and defence. Study 2: The purpose of this study was to determine how the pitch size affected the appearance of the different technical tactical behaviours of the goalkeeper in the offensive and defensive phase of the game when playing in three different SSGs. Three different pitch sizes were defined (62 x 44 m; 50 x 35 m; 32 x 23 m). A descriptive analysis of the variables used was performed to define the distribution of the data gathered. The Fisher´s exact test was used when the expected distribution was below 5 or included values below 1%. Statistical significance was set at p <0.05. The results of this study shows that the pitch size affects the behaviour of the goalkeeper and it should be taken into account when designing tasks by coaches focusing on technical and tactical actions, both in defensive and offensive phases. Study 3: The main goal of this article was to define how the pitch size of three different SSGs affected the physical demands and the tactical demands of the goalkeeper. Three professional goalkeepers take part in this research. Three different pitch sizes were designed (62 x 44 m; 50 x 35 m; 32 x 23 m). Positional data of each goalkeeper was recorder by using a 18 Hz global positioning system (GPS) device. A one-way analyse of the variance (ANOVA) and a Magnitude-base inference (MBI) was performed to assess the statistical analysis. The results showed that the absolute distances covered by the goalkeeper was higher when comparing the small SSG with the medium and large. When comparing the intensities among the three scenarios, only in the walking and the jogging intensity were found variances. Regarding to the tactical variables, all three variables increased when comparing the small SSG with the medium SSG and the large SSG. This thesis is the first work focused on the analysis of the performance of the goalkeeper in a SSG. How the pitch size of three different SSG was compared among the technical, tactical and physical demands of the goalkeeper. In general, it can be stated that the pith size affects the performance of the goalkeeper. Further research on how other modifications can affect those demands and defining better physical variables based on the real demands of the goalkeeper would help to a better understanding of the topic.