Cyclic Sighing
Two inhales, one long exhale. The strongest recent evidence for a brief breathing practice.
About 3 minutes
What to do
- Sit or lie comfortably.
- Breathe in slowly through your nose, filling the lungs to about two-thirds.
- Take a short second inhale through your nose to fully fill the lungs.
- Exhale slowly and completely through your mouth. Let the exhale be longer than the combined inhales.
- Repeat for about three minutes (around twenty cycles).
The exact pace is less important than the shape. Most people settle into six to ten cycles per minute. Don't force any phase.
Why it works
The double-inhale-then-extended-exhale pattern is sometimes called the "physiological sigh." It mirrors how the body naturally sighs when it needs to reset breathing or release tension. The short second inhale opens collapsed alveoli (tiny air sacs in the lungs), and the long exhale clears carbon dioxide and activates the parasympathetic nervous system.
A 2023 randomized controlled trial compared cyclic sighing to box breathing, cyclic hyperventilation, and mindfulness meditation over 28 days of daily five-minute sessions. Cyclic sighing produced the largest improvements in positive affect and the greatest reduction in baseline respiratory rate. The effects persisted outside the practice window.
Guided breathing
Evidence
Rating: strong
Cyclic sighing has the strongest recent randomized evidence of any brief breathing protocol. A 2023 trial randomized adults to one of four practices (cyclic sighing, box breathing, cyclic hyperventilation, or mindfulness meditation), each for about five minutes daily over 28 days. Cyclic sighing produced the largest improvements in positive affect and the greatest reduction in respiratory rate, including outside the practice itself.