Comparison of muscle strengthening exercise of quadriceps femoris with weight load and standing up from and sitting down on the chair using electromyography

The purpose of this study was to analysis how muscle strengthening exercise of quadriceps femoris with weight load on the chair reflects stand up from the chair. Ten healthy young adalt females (from 20 to 26 years of age) were informed and participated in this study. First trial was motions of stunding up from and sitting down on the chair. Second trial was motions of knee extension from 90° to 0° with 2kg weight load in sitting on the chair. In both traials, subject\u27s knee and hip angle and surface EMGs from quadriceps femoris (rectus femoris, vastus medialis and vastus lateralis) were recorded. In first traial, the three muscles activities were increased at motions of right after started standing up and motions of right before finished sitting down. In second traial, the three muscles activities were increased as knee angle approached more 0° and decreased as knee angle approached more 90° . There was no difference in patterns of muscle activities between three muscles at both traials. In comparison of muscle activities of motions of standing up from and sitting down on the chair and motions of knee extension from 90° to 0° with 2kg weight load in sitting on the chair, muscle activities of rectus femoris and vatstus medialis were more in the latter than in the former in all subjects. The results of this study leads our presumption that effect of muscle strengthening in quadriceps femoris highter in the latter than in the former. But, muscle activities of three muscles differented the former and the latter in knee angle. We conceive that muscle strengthening exercise in quadriceps femoris must be performed properly in consideration of that purpose, joint angle, weight bearing and several situations. From these points we might go on to an even more detailed examination of the function of qadriceps femoris concerned in standing up, standing and gait.国立情報学研究所の「学術雑誌公開支援事業」により電子化されまし