抄録
The purpose of this study was to acquire the knowledge of coaching concerning jump toss of the setter.
This study analyzed the transformation of motion by repetition training for acquisition of better jump toss
techniques. A college male volleyball player repeated the jump toss 5000 times in this training. Through
observation of preparatory phase for motion, this study analyzed the relation between the number of repetitions
and the resulting transformation of motion.
Results obtained are as follows:
1) As for the good position for the jump toss (front, center, back）.
a. The good setting was center position. This position increased through about 2500 times practice.
b. When the setter was in this good setting position, the rate of successful tossing increased.
c. The rate of successful tossing increased through about 5000 times practice.
2) As for the vertical good bodily positions (low, middle, high）.
a. The good setting was high position. This position increased through about 2500 times practice.
b. When it was good setting position, it was high position and the rate of successful tossing increased.
c. When the setter tossed in the high position, the trajectory of toss was ideal.
3) As for the transformation of compensational motion
a. The compensational motion with the arms and the legs decreases through about 5000 times practice.
b. Even if the rate of successful tossing increased, the compensational motion appeared again.
4) Transformation of time for taking off.
a. The time required for taking off decreased through about 2500 times practice.
b. The time for taking off influences jumping height.
Moreover, few transformations of motion were seen in the first term. They increased in the middle term,
and the rate of successful tossing increased in the last term. Finally, the ability of space criterion for timing
improved ahead of the ability of time criterion for timing.
