Some explication of skills in baseball batting

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The main purpose Of this Study is to understand skillful batting motions and to explicate the skills which actualized them, and also to search the research method for them. The Secondary purpose to analyze the effect of the air resistance to a fly ball. For the latter, we compared the actual flying distance and the distance which was calculated on initial velocity of a batted ball supposing to fly in a vacuum. In our an experiment, the latter average was 78.8 m for the former average of 96.7 m. And the divergence in vertical direction to that of initial velocity was the average of 20.0 m.The main result for the main purpose are as follows. (1) The trajectories of a bat in Cuban subjects look like an egg-oval throughout a swing in the horizontal plane, contrarily in Japanese subjects like the crescent-shaped. the former is extended to the direction that the pitched ball is coming. (2) As to the times from the start of forward swing to the impact (swing-time), Cuban subjects is the short … More est. In the subjects with long swing-time, the trajectories of a bat through the start take the shape of almost two fan, one of which is piled up upright on another one's apex, either in the horizontal plane and in the vertical plane. In the subject with short swing-time the joining point of those is near the head of bat, or the trajectories take the shape of almost an triangle. (3) In terms of the timing of the hip movements, Japanse subjects started in the first part of the swing, and Cuban subjects just before the impact. The style of swing in Cuban subjects is to move their own body like a spring, for that of Japanese subjects like a whip. For, in a spring one side is fixed, and before the operation the energy has been stored. But in a whip after one side moved, the energy is stored because of it. (4) Cuban subjects started their grip moving moderately inside-out and moderately down at forward swing, and to do them toward the front side of shoulder-elbow-grip plane and gradually to the normal direction to the plane. But this features are shared with some Japanese subjects. Less