Shoulder Muscle Activity during Selected Skills on the Uneven Parallel Bars

Abstract

Abstract The purpose of this study was to investigate the relationship of activity in selected shoulder muscles to the degree of swing on the uneven parallel bars. Muscle activity was measured electromyographically using surface electrodes on the following muscles: pectoralis major; anterior, middle, and posterior deltoids; biceps brachii; superior and inferior heads of the trapezius; and latissimus dorsi. A strength test was given to determine muscle activity during maximal contraction. A percentage of maximal contraction for each muscle was then calculated during the swing phase of the following skills: a stationary hang into a squat on the low bar, a jump-catch swing into a squat on the low bar, a cast-off the high bar into a pike around the low bar, and a cast-off the high bar into a back hip circle on the low bar. A videotape of the performance was used to determine the duration and range of the swing phase of each skill. The results indicated that activity of the selected muscles increased with an i...