Motion Analysis of Standing Sequence Based on Vertical Force Measuring with a Use of Force Plates

Abstract

The motion of standing sequence initiated from four different types of sitting positions was analysed based on the total vertical force (TVF) with a use of four force plates and at the same time, the force applied on the handrail located on the right of the subjects was measured. The subjects were seventeen helthy adult women. They were 18 to 21 years old with an average age of 19.2 years.
The standing sequence was categorized in five phases as follows: 1. initiative phase, 2. preparative phase, 3. sitting to standing phase, 4. up righting phase, 5. balancing phase.
At the first phase, TVF has decrease to 99% because of the weight was slightly shifted to down and backward to create the force forwardly. At the second, TVF has varied to 96% becouse of creating the force forwardly activating upper body flexion. At the third phase, TVF has incresed to 119% primarily activating the knee extention to create the force upwardly. At the fourth phase, TVF was decrease to 80% as the upward force has diminished. At this phase, the center of gravity of the total vertical force has shifted from the heel to the middle point of foot. At the fifth phase, TVF has revealed 100% becouse of neither the motion nor the force was necessary upward and forwardly. Then, the standing balance has kept as a natural standing posture.