A study was conducted to clarify factors that influence the learning effect of overhand-throwing, focusing on physical fitness and throwing motion before learning. Twenty-two boys and 24 girls in the second grade of elementary school, and 24 boys and 29 girls in the fifth grade carried out a learning program comprising four kinds of teaching materials. To improve their throwing motion, they carried out the program seven times for 15-20 min as a physical education class during a three-week period. Tennis ball throwing distance was measured, and the subjects' throwing motions were video- taped and evaluated by the observation method. At the same time, physical fitness and imitation ability were tested. As there was no significant correlation between the learning effect of throwing motion, and physical fitness and imitation ability in the group of second grade girls, it was thought that proper acquisition of throwing motion led to the improvement of throwing distance. In the group of fifth grade boys, those with a lower physical fitness level showed a large throwing motion learning effect. In the second grade boys and fifth grade girls groups, the imitation ability of the lower limb was one of the factors that influenced the learning effect. These results suggest that proper motor learning of overhand throwing has the possibility of improving throwing ability, and that some conditions present before learning, such as throwing motion, physical fitness and imitation ability, influence the degree of the learning effect.
