Immediate effects of respiratory muscle stretching on chest wall kinematics and electromyography in COPD patients

This study evaluated the immediate effects of respiratory muscle stretching on chest wall kinematics and electromyographic activity in COPD patients. 28 patients with COPD were randomized into two groups: 14 to the treatment group (TG) and 14 to the control group (CG). The TG underwent a stretching protocol of the rib cage muscles, while the CG remained at rest under similar conditions. After a single session, TG increased the tidal volume of the pulmonary rib cage (Vrcp) (p = 0.020) and tidal volume of abdominal rib cage (Vrca) (p = 0.043) variations and their percentages in relation to the thoracic wall, Vrcp% (p = 0.044) and Vrca% (p = 0.022). Also, TG decreased the end-expiratory Vrcp (p = 0.013) and the end-inspiratory Vrcp (p = 0.011) variations. In addition, there was a reduction in respiratory rate (RR) (p = 0.011) and minute volume (MV) (p = 0.035), as well as an increase in expiratory time (Te) (p = 0.026). There was also an immediate reduction in sternocleidomastoid (p = 0.043) and upper trapezium (p = 0.034) muscle electrical activity. Then, the study supports the use of stretching to improve COPD chest wall mobility with positive effects on chest wall mechanics, on volume distribution and electromyography.