The Effects of Push-ups with the Trunk Flexed on the Shoulder and Trunk Muscles.

[Purpose] The purpose of this study was to compare the activity of the shoulder and trunk muscles in two push-up positions: standard push-ups and push-ups with the trunk flexed. [Subjects] Fifteen young adult males participated in the study. [Methods] This study measured the clavicular and sternocostal portions of the pectoralis major, the serratus anterior, and the rectus abdominis during push-ups under the two conditions. [Results] The activity of the sternocostal portion of the pectoralis major and that of the rectus abdominis were significantly greater under Condition 1 than under Condition 2. The activity of the clavicular portion of the pectoralis major and that of the serratus anterior were significantly greater under Condition 2 compared with Condition 1. [Conclusion] These results indicate that exercises can selectively activate muscle parts under different clinical situations.