Abstract
In order to examine the basic traits of postural sway in standing posture on two feet, a new measureable analysis was devised in the study of static equilibrium. Using an XY recorder, the movements of the center of gravity in the standing posture were recorded for about I minute in 26 normal subjects, including 6 left footed persons. These records were measured in the following factors; the area, the angle, maximum length (Lα), width and Lα/width. Then, these records were also classified into 3 patterns (lateral, right declivity, and lengthwise) by the angle and into 4 patterns (concentrating, diffuse, shifted, and mixed) by the form of concentration of the center of gravity. There were statistically significant differences only in the area and the form of concentration according with the subject's footedness. But, in general, as the angle of the sway increased, the area La and width also tended to increase, and the sway became more diffuse. The results were discussed mainly from the point of psychology in the control of postural sway on two feet.
