ABSTRACT
Schoberth describes unsupported seated postures in which the body's weight is solely supported by the buttocks and feet. The postures are characterized by the location of the upper trunk's centre of gravity relative to the ischial tuberosities. The outcome measures were tolerance time, centre of gravity displacement, pain location and intensity. The purpose of the present study is to determine the extent to which posture and centre of gravity (CG) displacement affect seating tolerance in both the middle and anterior position. The chair was bolted to a force plate large enough to accommodate the chair and the subjects' feet, to determine centre of force in the vertical plane. Tolerance times for the four postures and number of pain responses related to the low back varied considerably among subjects, as demonstrated by the high standard deviations. The greatest effect on tolerance time resulted from the combination of forward shift of CG and forward flexion.
