Comparison of upper and lower trapezius electromyographic activity during Y-raise exercise with and without isometric adduction in healthy volunteers

BACKGROUND: Lower trapezius (LT) plays an important role in maintaining the stability of the scapula. Sufficient activation of LT can reduce the risk of rotator cuff tear and shoulder impingement syndrome. The Y-raise exercise has been recommended for effective LT activation. However, the upper trapezius (UT) can be co-activated during universal Y-raise exercise. OBJECTIVE: This study aimed to compare the activity of the UT, LT, and serratus anterior (SA) during Y-raise exercise with and without isometric adduction (IAD) using Thera-Band. METHODS: 21 healthy males voluntarily participated in the study. The participants were asked to perform Y-raise exercise with and without IAD using Thera-Band. Surface electromyography was used to measure the muscle activity of UT, LT, and SA during Y-raise exercise with and without IAD. Paired t-test was used to analyze the significance of the muscle activity of UT, LT, and SA as well as the activity ratio of LT/UT and LT/SA. The significance level was set at α= 0.05. RESULTS: Compared with Y-raise exercise without IAD, the muscle activity of UT and SA decreased (p= 0.001 and p= 0.003, respectively), whereas that of LT increased (p= 0.038) during Y-raise exercise with IAD. Additionally, the activity ratio of LT/UT and LT/SA was greater during Y-raise exercise with IAD (p= 0.001 and p= 0.001, respectively). CONCLUSION: Y-raise exercise with IAD using Thera-Band is recommended as an efficient exercise to selectively activate the LT and increase the activity ratio of LT/UT and LT/SA.