earticle

영어

The purpose of this study is to investigate the effect of scapular retraction exercises at different shoulder abduction angles on shoulder muscle activity to efficiently strengthen the muscles. This study was conducted with 30 healthy male participants in their 20s enrolled at G University. The reason for selecting adult males among the participants was to minimize bias in the results and reduce potential variables that could arise during data analysis. The experiments for this study began with a preliminary test in March 2024, and participants were recruited and the study was conducted by the end of april 2024. The participants positioned themselves against a wall with an attached protractor, and muscle activation was assessed during retraction exercises at 60°, 90°, and 120°. The muscles examined included the upper trapezius, middle trapezius, lower trapezius, and serratus anterior. Resistance was applied by having the participants hold an elastic band while abducting their shoulders, and they maintained each end position at the three angles for 10 seconds. The middle trapezius showed the highest muscle activity at 90° of shoulder joint abduction. This is because the lever arm is at its maximum length and has a more efficient line of force than the upper and lower trapezius during this movement. The upper trapezius showed the highest muscle activity as the angle increased, while the middle and lower trapezius showed the highest activity at 60° and 90°. The serratus anterior showed the highest activity at 60°. Therefore, it can be concluded that scapular retraction exercises are widely used in shoulder stabilizer exercises.