The purpose of this study is to conduct a comparative analysis of the right shoulder"s muscle activity when lifting ipsilateral and contralateral legs during the Push Up Plus (PUP) exercise, which is a typical shoulder stabilizing exercise, and to provide effective data for a shoulder stabilization exercise. Upper trapezius, lower trapezius, levator scapula, supraspinatus, infraspinatus, deltoid posterior, serratus anterior and pectoralis major, which are eight main muscles of a shoulder, were analyzed for the left and right leg lifting by using an electromyogram (EMG). The study revealed that the muscle activities of the right shoulder"s upper trapezius, levator scapula, supraspinatus, serratus anterior and pectoralis major were higher when lifting an ipsilateral (right side) leg, compared to lifting a contralateral (left side) leg. Therefore, lifting an ipsilateral leg can be an effective method for enhancing the maneuverability (mobility) of the right shoulder when lifting a single leg.
