My Secret Weapon: The Physiological Sigh

One of my faves: A fast, effective technique for staying regulated whenever and wherever you are.

A sigh.

Though I often think of a sigh as the noise my husband makes in frustration (and a great reason to go back outside with the dogs), a sigh is actually a life-sustaining reflex that preserves lung function and our ability to stay alive.

What is a sigh? It’s a natural reflex that preserves the efficacy of the alveoli — the half-billion, delicate tiny sacs in the lungs where oxygen enters the bloodstream, and carbon dioxide leaves it.

On a daily basis, the average human sighs once every five minutes. That’s about 288 times a day. But here’s the thing — we can also sigh on a voluntary basis.

Sighing activates the parasympathetic nervous system (rest+digest). As we discussed previously, this decreases our heart rate, slows our breathing rate, and can be a deeply soothing experience in times of anxiety or stress.

This week, our experiment is to practice the physiological sigh:

A double inhale through the nose followed by a long, slow, extended exhale through the mouth.

Simple, right?

Before sharing this in visual, written, and video form, I want to remind you that The Healing Lab is all about honoring you. So, if you try this and discomfort continues to arise in your body and mind, and that discomfort grows into distress, please wash the experiment down the proverbial sink. Really. Choose YOU.

Remember, choosing yourself is the greatest act of healing any of us can ever do.

---

How to practice the physiological sigh

1. Find a comfortable position.

2. Double Inhale through your nose (without exhaling in between).

   1. The first inhale fully expands the lungs, and the second, smaller inhale helps inflate the tiny alveoli (air sacs) in the lungs that may have collapsed, thereby maximizing oxygen intake.

3. Slowly exhale out of your mouth.

   1. The long, slow exhale helps offload excess carbon dioxide (CO₂) from the bloodstream, which lowers physiological stress and activates the parasympathetic nervous system (the “rest and digest” state)

4. Repeat for five minutes.

---

Fun facts about the physiological sigh:

• Studies have shown that engaging in as few as 1-3 physiological sighs can empower an individual to stay or return to a calmer, more regulated state. (source)

• A recent clinical trial shows that if one practices cyclical physiological sighs – i.e., if one engages in continuous physiological sighs for five minutes, the practice can reduce an individual’s overall stress and enhance their overall mood. (source)

---

Science, Stories + Source Material

• Effect of Breathwork on Stress and Mental Health: A Meta-Analysis of Randomized-Controlled Trials — a meta-analysis by Emma L. Noble and James P. McIntyre

• How Breath-Control Can Change Your Life: A Systematic Review on Psycho-Physiological Correlates of Slow Breathing by Andrea Zaccaro et al.

• The Sigh from the Physiological Perspective by L.J. Severs et al.

• The Integrative Role of the Sigh in Psychology, Physiology, Pathology, and Neurobiology by Jan-Marino Ramirez

• A Sigh of Relief or a Sigh to Relieve: The Psychological and Physiological Relief Effect of Deep Breaths by E. Vlemincx et al.

• Respiratory Variability, Sighing, Anxiety, and Breathing Symptoms in Musicians by E. Vlemincx et al.

• UCLA and Stanford Researchers Pinpoint Origin of Sighing Reflex in the Brain by W.E. Ross et al.

---

That’s it from us in Vermont! Now, it’s time to frolic with my two girls in all the freshies. Goodness knows they have been oh-so patient this week as I nerded out fiercely about respiration so I could write this for all of you.

I hope you can find joy and a moment of refuge (in the snow or otherwise) this weekend and a deep breath somewhere along the way too.

Kindly,

Kate

---

Thank you, as always, for being here with us.

If this edition of The Healing Lab served you in any way, please consider sharing the post with a friend who might also appreciate it or commenting and liking here. It (is silly, but it) helps more than you know.

---