CHANGES IN POSTURAL SWAY RELATED TO AGE / 体力科学

ABSTRACT

The purpose of the present study is to investigate the changes in postural sway (PS) related to age quantitatively. The movement in the center of gravity of the body projected into the base of support was used as a criterion of PS. It was measured in 45 subjects, 23 males and 22 females, ranging in age from 22.1 to 68.1. The subjects maintained erect posture with feet together for about 2 minutes with eyes open, and thereafter with eyes closed respectively. The measurement of PS has been made by measuring the weight at two points of the supporting platform. The degree of PS was calculated by using an electronic computer (HITAC-10-II) . The following results were obtained.<BR>1. The displacements of body's center of gravity per 1 minute with eyes open as well as with eyes closed increased with age. The PS, however, showed a gradual increase with eyes open, and then it did a steep increase with eyes closed from the age of fifties.<BR>2. The PS was reduced to two components, i.e., lateral (X) and antero-posterior (Y) ones. The ratio of the Y component to the X one (Y/X) with eyes open as well as with eyes closed showed a gradual decrease with age.<BR>3. The ratio of X component with eyes closed to that with eyes open was calculated as well as the ratio of Y component. At all ages the ratio in X component was larger than that in Y component.<BR>4. Judging from both the steep increase in PS with eyes closed and the gradual increase with eyes open with age, there seems to exist the modification of static equilibration mechanism in the aged, especially the much degradation of some regulatory function other than visual one.