• Kosei Katsuzaki
  • Takeshi Sato
  • Takayuki Watanabe
  • Masami Miyazaki
  • Shoji Igawa
Keywords: professional, pitching, DLT


The objective of this study was to analyze three-dimensional motion chains of pitching movement, and determine how the chains of movement of the limbs were working together from the lower extremities to the upper extremities. There were devided three experimentals group for compareing the motion skills: professional (n=9), amateur (n=9), and high school (n=9) baseball players. The pitching motion recorded for all subjects performed the maximum their effort from the mound for throwing the ball. It was recorded in videotapes by two high-speed cameras to arrange places. Then four points of every picture were digitized per 1/500 second. Three-dimensional coordinates for the segment endpoints were computed by a direct linear transformation (DLT) method. The resultof this study, linking the lower and upper body, professional picher could move the body efficiant and give the speed for ball. on the other hand, it was found that amatur and high school picher could not move the body efficient becouse to move the shoulder of piching side to piching direction.