Electrical impedance tomography will be used to verify the effect of the lateral posture and associated breathing techniques in COPD and healthy individuals. The subjects will be placed in a standardised position before the measurements begin. The subjects will be placed in a right lateral recumbency position. The protocol comprises four manoeuvres, each interrupted by a short rest phase. Each subject will begin the experiment with the spontaneous ventilation manoeuvre in order to obtain the reference ventilation distribution. This will be followed by four other manoeuvres during which ventilation was measured: 1) using an spirometer to obtain a tidal volume of 1L, 2) performing the ELTGOL technique independently, 3) performing the ELTGOL technique assisted by manual pressures applied by a physiotherapist. 4) using a positive expiratory pressure (PEP) device.
