Physiological sigh

A physiological sigh is a double inhale through the nose followed by a long exhale through the mouth; it can rapidly reduce stress. 1

• How to do it: Take a deep inhale through your nose, add a second brief nasal inhale to fully inflate your lungs, then exhale slowly through your mouth until your lungs are empty. 2
• For rapid calm: One sigh—and sometimes two or three—can quickly lower stress and help shift the body toward calm, including in high-pressure moments. 3
• Natural sighs: The body also produces sighs spontaneously during sleep and at other times; the second inhale reinflates small air sacs in the lungs that may have collapsed, supporting gas exchange. 4
• During running: For a right-side stitch, two or three physiological sighs while continuing to run may ease the pain; Huberman links the effect to changes in sensory feedback from the phrenic nerve. 5