Analysis of the Effect of Visuals on the Stabilization of Trunk Muscles During Rotational Motion

摘要

Seated balance, especially for the application of wheelchair users, has become an area of interest for researchers. Numerous studies have been done to date, which analyze the effects of wheelchair propulsion on shoulders and limbs, but little study has been done in regards to trunk muscles and their stabilization effects. Therefore, for this study, motorized rotational motion at a rotational angle of 45 degrees was performed on nine subjects in both the forward and backwards directions of motion. Eight abdominal and back trunk muscles (rectus abdominis, external oblique, thoracic erector spinae, and lumbar erector spinae) were analyzed via electromyography (EMG). In addition, the effect of the presence of virtual reality was analyzed on the muscle activity. Each trial was made up of four randomized test, and were performed three times each on each subject for accuracy purposes. The acquired raw signals were processed in MATLAB, and their results were analyzed. It was found that the most muscle activity was present in the forward rotational direction while visuals were playing on the screen in front of the subject. This indicates, that it is under that condition that the muscles work their hardest in order to stabilize the body and maintain balance.