[Objective] To clarify the effects of the difference of loading methods and loads on muscle activity of the agonist muscle, antagonist muscle and the distal muscle. [Method] With 16 healthy female adultsʼdominant hand upper limb as subjects of study, at the elbow flexion angle of 90 degrees, 4 different load types from 10% to 70% maximum voluntary isometric contraction were used. In addition, Two loading methods were adjusted by ʻself-adjustmentʼwhere the subject looks at a display screen, and by ʻothers adjustmentʼwhere the adjustment is done by the examiner. [Result] AccordingtotheTwoway analysis of variance (ANOVA), both the weight loads difference and the loading methods had significant effect on the agonist muscle and the distal muscle. However, only the weight loads difference had a significant effect on the antagonist muscle. [Conclusion] Together with the increase of weight loads to the agonist muscle, the muscle activity of the agonist muscle, the antagonist muscle and the distal muscle also increased. Besides that,the muscle activity of the agonist muscle and distal muscle are higher in ʻothers adjustmentʼcompared to ʻself-adjustmentʼ.
