Investigation of the EMG activity of erector spinae and trapezius muscles during Islamic prayer (Salat)

Abstract

This study aimed to investigate the electrical activity of two muscles located at the dorsal surface during Islamic prayer(Salat). Specifically, the electromyography (EMG) activity of the erector spinae and trapezius muscles during four positionsobserved while performing Salat, namely standing, bowing, sitting and prostration, were investigated. Seven adult subjects withan average age of 28.1 (± 3.8) years were included in the study. EMG data were obtained from their trapezius and erector spinaemuscles while the subjects maintained the specific positions of Salat. The EMG signal was analysed using time and frequencydomain features. The results indicate that the trapezius muscle remains relaxed during the standing and sitting positions while theerector spinae muscle remains contracted during these two positions. Additionally, during the bowing and prostration positions ofSalat, these two muscles exhibit the opposite activities: the trapezius muscle remains contracted while the erector spinae muscleremains relaxed. Overall, both muscles maintain a balance in terms of contraction and relaxation during bowing and prostrationposition. The irregularity of the neuro-muscular signal might cause pain and prevent Muslims from performing their obligatoryprayer. This study will aid the accurate understanding of how the back muscles respond in specific postures during Salat.