Introduction:
In the field of sports science, there are two major methods of motor learning: Blocked Practice and Random Practice. Blocked Practice is based on the Closed-Loop theory and involves consciously repeating a desired movement. However, Blocked Practice takes time to consolidate skills, making it challenging to adapt them in competitive situations. In contrast, Random Practice, which is based on Schema theory, involves practicing multiple tasks in a random order to acquire movements unconsciously. Because this method involves unconscious learning, progress may not be obvious, but it enhances the ability to apply skills in competitive environments. However, we have been exploring a method that enables rapid skill acquisition and effective adaptation to competitive situations while practicing specific techniques. Therefore, inspired by Lyndon’s "old way/new way" approach, we developed "Comparative Practice," which promotes the stabilization and development of skills by alternating between similar but different movements while comparing them.

Objective:
This study aimed to analyze and compare the psychological processes involved in Blocked Practice and Comparative Practice using text mining, in order to clarify the differences between the two methods and assess the effectiveness of Comparative Practice for skill acquisition.

Methods:
The study involved 22 university volleyball players learning the short serve. Participants were divided into two groups: Blocked Practice (BL) and Comparative Practice (CP). Participants reviewed videos of their own serves and decided which movements they wanted to modify. The CP group practiced alternating between short and long serves, while the BL group only practiced short serves. Text mining was used to clarify the differences in psychological processes (i.e. problem identification, solution strategies, insights during practice, and reflections from competitive scenarios) between the CP and BL group. We compared psychological processes between groups using Yates’ chi-square test. Further, we assessed performance outcomes with a two-way ANOVA, focusing on the number of successful serves placed in the target area before and after the experiment.

Results:
The CP group showed a significant improvement in short serve performance (pre-test mean: 1.67, SD: 1.61; post-test mean: 3.00, SD: 2.09; p < .01), whereas the BL group did not (pre-test mean: 2.00, SD: 2.26; post-test mean: 2.10, SD: 1.73; ns). In the text mining analysis results, the CP group placed more emphasis on "tossing technique" (CP: 34%, BL: 18%, p < .05) and "hitting technique" (CP: 18%, BL: 6%, p < .05) than the BL group. No significant differences were observed in "body movement," "hitting position," or "ball trajectory." Introspective descriptions revealed that the CP group exhibited greater self-awareness of differences in their own movements, thought about how they could improve their movements, and corrected them.

Conclusion:
The study revealed significant differences in both the number of successful serves and the psychological processes during practice between the CP and BL groups. These findings suggest that Comparative Practice increased introspection about one’s own movements, thereby improving performance. This approach may be beneficial not only for volleyball serves but also for acquiring various sports skills in physical education settings.

Keywords: Comparative Practice, Blocked Practice, text mining, discrimination, motor learning.