Abstract des Autors

The purpose of this study was to examine the effects of the practice variability from a developmental point of view. The effects of practice variability were analysed with reference to two factors; (a) throwing distance, and (b) throwing direction. Subjects were 192 males; 64 preschool elementary school children and college students respectively. The task assigned was to throw 100 g beanbags at specified target sat in a fixed chair. All subjects practiced four blocks of 8 trials giving a total of 32 trials. After that, 2 test blocks of 8 trials were given. In the first test block, the target was placed on the standard target (criteria distance and direction). In the second test block, the target was placed on the transfer distance and direction not experienced in practice trials. Subjects in each age group were randomly divided into four groups according to practice condition. The results were as follows: 1. Preschool and school children assigned a variety of practice performed significantly better than specific-practice group. 2. For preschool children, there was significant variability effect in direction factor. 3. For school children, there was significant variability effect in distance factor. 4. For college students, there were no variability effects, both in distance and direction factors. From these results, it is suggested that there is the best period and the best parameter of variability fo rpractice variability to operate effectively. (gekürzt)