Abstract
[Purpose] In this study, we investigated the influence of slipped posture in bed-backrest on the activity of respiratory muscles and energy consumption. [Subjects] Twenty-one young healthy men (mean age 27 ± 4.4 years) were investigated in the present study. [Methods] Surface electromyograms were recorded for five respiratory muscles (sternocleidomastoideus muscle, trapezius muscle, back muscles, rectus abdominal muscle, and oblique abdominal muscle). The energy consumption was measured by calorimetry. We measured these values in three types of bed-backrest posture: posture 1, head-up 60° and knee flexes at 20°; posture 2, head-up 60°; and posture 3, slipped. [Results] The electromyographic activity (202.1%) of the rectus muscle during expiration was significantly higher in posture 3 than any of the other postures (98.2% in posture 1, and 100.0% in posture 2) (p<0.05). The energy consumption (123.2%) was significantly increased in posture 3 compared to posture 2 (100.9%) (p<0.05). [Conclusion] The slipped posture in bed-backrest enhances tonic activity in respiratory muscles and increases energy consumption by augmenting minute ventilation.
