Paradoxical respiratory motion is a pathological respiratory motion caused by trauma to the chest, multiple ribs or multiple rib fractures in the lungs, and softening of the chest wall without the support of the intact ribs. During normal breathing, the thorax is elevated during inspiration, which increases the volume of the thorax and increases the negative pressure, which helps gas enter the lungs, and during exhalation, the chest wall is lowered, which decreases the volume of the thorax and decreases the negative pressure, which helps gas exhale from the lungs. Paradoxical respiratory exercise is the opposite of this situation, which causes the thorax to fall during inspiration, instead of increasing the negative pressure, and decreases the negative pressure in the thorax during exhalation, making the pressure increase to affect normal breathing.