This study compared and analyzed the effects of a circuit training program on the knee joint muscle function of 20 female volleyball club members in their 30s, and the following conclusions were drawn.
1. The results of the study on the right extensor muscle strength showed significant differences between groups and by time point, and the interaction effect between groups and by time point also showed significant differences. 2. The results of the study on the right flexor muscle strength showed significant differences between groups and by time point, and the interaction effect between groups and by time point also showed significant differences. 3. The results of the study on the left extensor muscle strength showed no significant differences between groups and by time point, but the interaction effect between groups and by time point showed significant differences. 4. The results of the study on the left flexor muscle strength showed no significant differences between groups, but the interaction effect between groups and by time point showed significant differences. In addition, the interaction effect between groups and time points showed a significant difference . 5. The research results of the right extensor/flexor ratio showed no significant difference between groups, but there was a significant difference by time point. In addition, the interaction effect between groups and time points showed a significant difference. 6. The research results of the left extensor/flexor ratio showed no significant difference between groups, but there was a significant difference by time point . In addition, the interaction effect between groups and time points showed a significant differenc. In other words, the 12-week regular circuit training program of this study produced overall positive research results on the isokinetic muscle function of female volleyball players.