Physiological Sigh

What is Physiological Sigh?

The physiological sigh is a breathing pattern your body produces spontaneously — every few minutes during sleep, and when you sob deeply as a child. It consists of a full inhale, a second short “top-up” inhale, then a long, extended exhale.

Done deliberately for a few minutes (called cyclic sighing), it has become one of the most talked-about calming techniques thanks to research from Stanford University.

How to do Physiological Sigh, step by step

1. Breathe in through your nose until your lungs feel about two-thirds full.
2. Without exhaling, take a second short sip of air through the nose to fill them completely.
3. Exhale slowly and fully through your mouth — make it twice as long as the inhales.
4. Repeat for 1–5 minutes. Even one or two sighs can noticeably reduce tension.

What the science says

Tiny air sacs in the lungs (alveoli) gradually collapse during stress and shallow breathing. The second inhale pops them open again, improving gas exchange, while the long exhale efficiently releases carbon dioxide and engages the calming parasympathetic system.

In a 2023 randomised study, five minutes a day of cyclic sighing for a month produced greater improvements in mood and a larger reduction in breathing rate than mindfulness meditation or other breathing patterns (Balban et al., 2023, Cell Reports Medicine).

Benefits of Physiological Sigh

Tips for better practice

• The second inhale is short — think of it as topping up a glass.
• Make the exhale unhurried; that is where most of the calming happens.
• Use it as a reset between tasks or after a stressful message.

Safety notes

Frequently asked questions

References

1. Balban M.Y. et al. (2023). Brief structured respiration practices enhance mood and reduce physiological arousal. Cell Reports Medicine.