Time-motion analysis of goalball players in attacks: differences of the player positions and the throwing techniques.

In this study, we aimed to analyse goalball players time-motion variables (distance covered, time spent, maximum and average velocities) in official goalball match attacks, taking into account the attack phases (preparation and throwing), player position (centres and wings) and throwing techniques (frontal, spin and between the legs). A total of 365 attacks were assessed using a video based method (2D) through manual tracking using the Dvideo system. Inferential non-parametric statistics were applied for comparison of preparation vs. throwing phase, wings vs. centres and, among the throwing techniques, frontal, spin and between the legs. Significant differences were found between the attack preparation versus the throwing phase for all player time-motion variables: distance covered, time spent, maximum player velocity and average player velocity. Wing players performed most of the throws (85%) and covered longer distances than centres (1.65 vs 0.31 m). The between the legs and the spin throwing techniques presented greater values for most of the time-motion variables (distance covered, time spent and maximum player velocity) than did the frontal technique in both attack phases. These findings provide important information regarding players' movement patterns during goalball matches that can be used to plan more effective training.

Development and evaluation of an observational system for goalball match analysis / Desenvolvimento e avaliação de um sistema de observação para análise do jogo de goalball / Desarrollo y evaluación de un sistema de observación para el análisis del juego del goalball

Abstract Our purpose was to develop and evaluate an observational system for goalball match analysis. We used a non-participant systematic game observation method including eight elite games, video recorded, and randomly chosen. Observational categories and performance indicators were determined for each offensive (i.e., ball control, attack preparation, and throwing) and defensive principles (i.e., defensive balance, throw reading, and blocking). The comprehensive method of development and the ideal reliability levels (kappa coefficient of 0.81-1.00) of this protocol ensure the generation of quantitative and qualitative information for players and coaches and the rigor required for scientific use.

Resumo Nosso objetivo foi desenvolver e avaliar um sistema de observação para análise do jogo no goalball. Foi usado um método de observação sistemática não participante, incluindo vídeos de oito jogos de elite escolhidos aleatoriamente. Categorias de observação e indicadores de desempenho foram determinadas para cada princípio ofensivo (i.e., controle de bola, preparação do ataque e efetivação do arremesso) e defensivo (i.e., balanço defensivo, leitura da trajetória e interceptação do arremesso). O abrangente método de desenvolvimento e os níveis de confiabilidade ideais (coeficiente kappa de 0,81-1,00) desse protocolo asseguram a geração de informações quantitativas e qualitativas para jogadores e treinadores e o rigor necessário para uso científico.

Resumen Nuestro objetivo fue desarrollar y evaluar un sistema de observación para el análisis del juego del goalball. Se utilizó un método de observación sistemática no participante, que incluía vídeos de ocho juegos de élite elegidos al azar. Se determinaron las categorías de observación y los indicadores de rendimiento de cada principio ofensivo (p.ej., control del balón, preparación del ataque y lanzamiento) y defensivo (p.ej., equilibrio defensivo, lectura de la trayectoria e interceptación del lanzamiento). El método completo del desarrollo y los niveles de fiabilidad ideales (coeficiente kappa de 0,81 a 1,00) del presente protocolo aseguran la generación de información cuantitativa y cualitativa para jugadores y entrenadores, y el rigor necesario para el uso científico.