Manipulação da Restrição da Tarefa de Arremesso em Atletas Amadores de Handebol
Data
2019-11-27
Autores
Ribeiro, Gabriel Aguado 
Orientadores
Carvalho, Raquel de Paula
Tipo
Trabalho de conclusão de curso
Título da Revista
ISSN da Revista
Título de Volume
Resumo
No handebol, velocidade e precisão são características indispensáveis para o rendimento do arremesso, no entanto, a velocidade final da bola tem relação direta com o nível de rendimento de atletas. Este movimento, assim como os demais, está sujeito a restrições do organismo, do ambiente e da tarefa. Sendo assim, o objetivo deste estudo foi verificar como a manipulação da tarefa influencia o arremesso em atletas amadores de handebol. Para isso, 18 atletas amadores de handebol entre 18 e 27 anos foram recrutados e realizaram 10 arremessos para a tarefa de força, orientada pelo comando “com sua força máxima, no alvo”, e 10 arremessos para a tarefa de precisão, orientada pelo comando “no centro do alvo”. Foram fixados 8 marcadores em proeminências ósseas do voluntário para captura e posterior reconstrução 3D do movimento. As estratégias de movimento durante as fases de preparação e aceleração do arremesso foram analisadas através de variáveis cinemáticas angulares e espaço-temporais. Empregou-se o teste t de Student para amostras relacionadas. Foi usado o programa SPSS (Statistical Package for Social Sciences) e considerou-se nível de significância de p < 0,05. Foram encontradas diferenças significativas de variáveis espaço-temporais em ambas as fases de preparação (velocidade, trajetórias da mão, do acrômio, das espinhas ilíacas) e aceleração (velocidade, tempo, trajetória da espinha ilíaca póstero superior direita e razão entre as trajetórias de acrômio e espinha ilíaca póstero superior direita). Em geral, a tarefa de força apresentou maiores resultados que a tarefa de precisão, com exceção do tempo na fase de aceleração. As variáveis angulares também demonstraram alteração entre as tarefas, tanto para o início da preparação (ângulos de ombro e cotovelo), quanto para o fim da aceleração (ângulo de cotovelo). A tarefa de força apresentou maior índice de acerto e menor variação de desempenho em comparação à tarefa de precisão. Concluiu-se que as tarefas apresentam atratores distintos, modificadas pelo parâmetro de controle que envolvem a intencionalidade do movimento, ou aplicação de torque muscular motivado pelo comando verbal, e a demanda de precisão, representada pelo tamanho do alvo. Estes fatores influenciam o arremesso de atletas amadores de handebol de acordo com a demanda da tarefa.
In handball, speed and accuracy are indispensable characteristics for throwing performance. However, the final speed of the ball is directly related to the athletes performance level. This movement, just like others, is subject to constraints on the organism, the environment, and the task. Thus, the aim of this study was to verify how the manipulation of the task influences the throw in amateur handball athletes. Therefore, 18 amateur handball athletes were recruited and made 10 pitches for the strength task, guided by the command “with your maximum strength, on the target”, and 10 pitches for the precision task, oriented by the command “in the center of the target". Eight markers were set on the volunteer's bony prominences for capture and subsequent 3D reconstruction of the movement. Movement strategies during the preparation and acceleration phases of the pitch were analyzed using angular and spatiotemporal kinematic variables. Student's t-test was used for related samples. Statistical Package for Social Sciences (SPSS) software was used and a significance level of p <0.05 was considered. Significant differences in spatiotemporal variables were found in both phases of preparation (velocity, trajectory of hand, acromion, iliac spine) and acceleration (velocity, time, trajectory of right superior posterior iliac spine and ratio between acromial and right superior posterior iliac spine trajectories). The strength task generally presented higher results than the precision task, except for the acceleration phase time. Angular variables also showed alteration between tasks, both at the beginning of preparation (shoulder and elbow angles) and for the end of acceleration (elbow angle). The strength task presented higher hit rate and smaller performance variation compared to the precision task. It was concluded that the tasks have different attractors, modified by the control parameter involving the intentionality of movement, or application of muscular torque motivated by verbal command, and the demand for precision, represented by the target size. These factors influences the throwing of handball amateur athletes according to the demand of the task.
In handball, speed and accuracy are indispensable characteristics for throwing performance. However, the final speed of the ball is directly related to the athletes performance level. This movement, just like others, is subject to constraints on the organism, the environment, and the task. Thus, the aim of this study was to verify how the manipulation of the task influences the throw in amateur handball athletes. Therefore, 18 amateur handball athletes were recruited and made 10 pitches for the strength task, guided by the command “with your maximum strength, on the target”, and 10 pitches for the precision task, oriented by the command “in the center of the target". Eight markers were set on the volunteer's bony prominences for capture and subsequent 3D reconstruction of the movement. Movement strategies during the preparation and acceleration phases of the pitch were analyzed using angular and spatiotemporal kinematic variables. Student's t-test was used for related samples. Statistical Package for Social Sciences (SPSS) software was used and a significance level of p <0.05 was considered. Significant differences in spatiotemporal variables were found in both phases of preparation (velocity, trajectory of hand, acromion, iliac spine) and acceleration (velocity, time, trajectory of right superior posterior iliac spine and ratio between acromial and right superior posterior iliac spine trajectories). The strength task generally presented higher results than the precision task, except for the acceleration phase time. Angular variables also showed alteration between tasks, both at the beginning of preparation (shoulder and elbow angles) and for the end of acceleration (elbow angle). The strength task presented higher hit rate and smaller performance variation compared to the precision task. It was concluded that the tasks have different attractors, modified by the control parameter involving the intentionality of movement, or application of muscular torque motivated by verbal command, and the demand for precision, represented by the target size. These factors influences the throwing of handball amateur athletes according to the demand of the task.
Descrição
Citação
RIBEIRO, Gabriel Aguado, Manipulação da Restrição da Tarefa de Arremesso em Atletas Amadores de Handebol. 2019. 51 f. Trabalho de conclusão de curso de graduação (Educação Física) - Instituto de Saúde e Sociedade (ISS), Universidade Federal de São Paulo (UNIFESP), Santos, 2019.