The purpose of this study was to obtain basic data for advancing game performance by clarifying the effects of static stretching, dynamic stretching, clenching and shouting on knee extension strength. The knee extension strength of a total of thirty eight people (thirty four healthy young men and four young women) divided into various groups were measured with a digital back strength meter. The following results were obtained:

1. The knee extension strength increased significantly for the dynamic stretching plus warming up group and the shouting group;

2. The knee extension strength decreased significantly for the static stretching group;

3. There was no significant difference in the knee extension strength for the clenching group, however, there were significant effects depending on the individual.

According to the results, in advancing game performance for athletes, it is important for them to use dynamic stretching and shouting corresponding to the situation while static stretching should be used modestly before the main game performance. Clenching can be used for advancing game performance for those who have shown effective results.