The aim of this study to investigate the effects of craniocervical flexion on muscle activities of scapular upward rotators during push-up plus exercise in subjects with winging scapula. Eighteen males with scapular winging were recruited, and each subject performed knee push-up plus and other exercises, in two conditions (craniocervical flexion vs. natural head positions). A surface electromyography (EMG) was used to measure upper trapezius (UT), serratus anterior (SA), and lower trapezius (LT) muscle activity. A paired t-test was used to determine the statistical significance between the different condition with/without applying of craniocervical flexion. UT EMG activity significantly decreased and SA EMG activity significantly increased during knee push-up plus involving the craniocervical flexion compared to the natural head position. However, no significant differences (p>.05) were found in the activity of the LT muscle. The UT/SA ratios with and without craniocervical flexion showed a significant difference (p<.05). These results showed that the knee push-up plus other exercises performed with craniocervical flexion could strengthen the serratus anterior muscle and minimize the activity of the UT muscle.

• Si-jeong Song(Dept. of Physical Therapy, The Graduate School, Yonsei University)
• One-bin Lim(Dept. of Physical Therapy, The Graduate School, Yonsei University)
• Jeong-ah Kim(Dept. of Physical Therapy, The Graduate School, Yonsei University)
• Joon-hyoung Yong(Dept. of Physical Therapy, Hallym Polytechnic University)
• Heon-seock Cynn(Dept. of Physical Therapy, College of Health Science, Yonsei University, Dept. of Ergonomic Therapy, The Graduate School of Health and Enviroment, Yonsei University)
• Chung-hwi Yi(Dept. of Physical Therapy, College of Health Science, Yonsei University, Dept. of Ergonomic Therapy, The Graduate School of Health and Enviroment, Yonsei University) Corresponding author