Comparing shoulder girdle muscle activation during two yoga poses in female athletes with and without scapular dyskinesis

Purpose Many yoga poses involve supporting part or all of the body weight on the shoulder girdle and arms, which impose high loadings on the shoulder girdle. The present study aims to investigate the differences in electromyographic (EMG) activity of shoulder muscles in female yoga athletes with and without scapular dyskinesis (SD) during two yoga poses. Methods This cross-sectional analytical survey study included 24 female athletes aged 18–40 years with ( N = 12) and without ( N = 12) scapular dyskinesis from a yoga club in Tehran, Iran. EMG (Aktos; Myon, Inc.) data were collected to measure the peak activation of the shoulder girdle muscles, including: upper trapezius, lower trapezius, serratus anterior, infraspinatus, posterior deltoid, and teres major of the dominant side, explicitly focusing on their electrical activity during the two yoga poses, Chakrasana and Pincha Mayurasana. An independent T -test and Mann-Whitney U test were used to analyze inferential statistics with a significance level of p ≤ 0.05. Results The results showed there is no significant difference between the with SD and without SD groups in the activity of the upper trapezius, serratus anterior, posterior deltoid, and teres major muscles during Chakrasana and Pincha Mayurasana poses ( P ≥ 0.005). In contrast, the two groups had significant differences in the lower trapezius ( P = 0.033) and infraspinatus ( P = 0.045). Specifically, lower trapezius activity was greater in the SD group, whereas infraspinatus activity was greater in the non-SD group. Conclusions This study suggests that scapular dyskinesis influences the activity of the infraspinatus and lower trapezius muscles during Chakrasana and Pincha Mayurasana poses. The data highlight the importance of targeted neuromuscular interventions to address muscular imbalances in the shoulder complex, especially in populations exposed to overhead and inverted movements, such as yoga practitioners.