Most kendo practitioners, from beginners to experts, repeatedly practice striking by making a large swing of the shinai overhead and then cutting down. We call this a “basic men-uchi”. In actual matches, however, no expert practitioner raises the shinai overhead but instead makes a compact swing, which we call a “practical men-uchi”. We addressed a fundamental question: is it really necessary to practice basic men-uchi in order to master practical men-uchi? We began by theoretically reanalyzing the dynamics of a single bar model, which showed that for obtaining a fast shinai tip speed, it is not effective to press the shinai in opposite directions with the right and left hands. This result suggested that the efficient motion of the shinai is composed of three processes: a quasi-translational motion, a 2-step braking motion, and an axis-free seesaw motion. Considering each process carefully, we found several advantages of practicing basic men-uchi in order to acquire skill in practical men-uchi. For example, to perform the quasi-translational motion well in the practical men-uchi, it is important to move the shoulders forcefully instead of moving the elbows or wrists. Repeating large swings is an appropriate training method for beginners to learn proper shoulders motions. However, practicing only basic men-uchi is not sufficient because some players have difficulty mastering practical men-uchi despite many years of training. We therefore propose that even beginners should practice practical men-uchi. Developing a coaching method based on our results is a pressing issue and progress in this matter is being made.
