THE RELATIVE POSITION OF "SEIKA-TANDEN" AND THE CENTER OF GRAVITY IN STANDING POSTURE

Abstract

The purpose of this study was to observe the positions of "seika-tanden" (the lower abdominal region) and the whole-body centers of gravity(CGs) in three sorts of standing postures (i. e. the relaxed, the standard and the corrected postures) , and to evaluate these postures applying the body alignment test and the degree of spinal curvature with a conformateur. The estimation of CGs was based on H. Matsui's body segment parameters by means of pictures in profile. The positions of tanden were obtained by H. Hida's and T. Yanagida's drawing figure methods. The subjects in this study were a trained man in "Seitai-Hou" and 13 untrained men. The results were as follows: 1) As to the characteristics in three postures estimated by the degree of spinal curvature, the relaxed and the standard posture tended to be "stoop" and "straight", respectively. While the corrected posture was characterized by the posture which showed the flatted back, the intense lumbar curvature, and the relatively projecting buttocks. 2) According to the results of the body alignment test, the score evaluated in the corrected posture for untrained men was lower than that in the standard posture, but the score for trained man in the corrected posture increased when changing from the relaxed posture to the corrected one. 3) The relative positions of tanden obtained by H. Hida's drawing figure method were in front of CGs in all postures. 4) Adopting T. Yanagida's drawing figure method, the positions of tanden (inner position) for both trained and untrained were fairly close to CGs in the corrected postures.