What is the physiological sigh

The physiological sigh is a natural breathing pattern that humans and animals use to regulate stress and enhance calmness. This technique involves a double inhale followed by a long exhale. By intentionally practicing this type of breathing, you can quickly reduce stress levels.

The physiological sigh works by reinflating small air sacs in the lungs, which may collapse under stress, helping to efficiently expel carbon dioxide and increase oxygen intake. This process can rapidly lower physiological arousal and promote relaxation in stressful situations. This sighing occurs naturally about every five minutes during both wakefulness and sleep, but can also be used intentionally to modulate stress responses effectively 1.

For instance, doing a double inhale, even with a small second breath, fills up more air sacs in the lungs. The long exhale that follows allows effective release of carbon dioxide, which in turn helps to reduce the body's alertness levels. This is considered one of the fastest ways to reduce stress responses in real-time, especially when mindfulness and meditation techniques may not be feasible 2 3.