There is a breathing exercise you have already done dozens of times today without noticing. Two in-breaths, then one long out-breath: the sigh. Your body does it by itself, in your sleep and after a moment that touched you. Do it consciously, and it is the fastest way there is to let a spike of tension or irritation settle. No cushion, no time, no special place needed. In this article you will read what the physiological sigh is, why that second in-breath makes the difference and when to use it. You can also breathe along with it right away below.
Breathe in through your nose until you are full, add a little more air on top, and then let it go long and audibly through your mouth until you are empty. Two or three times is enough. That second short in-breath is the whole trick: it reopens air sacs that collapsed during shallow breathing, so the long out-breath afterwards releases more carbon dioxide in one go.
The physiological sigh consists of two in-breaths through your nose in a row, followed by one long out-breath through your mouth. The first in-breath is an ordinary, full breath. The second is short and comes on top of it, as if you are scooping in one last bit of air while you are already full. Then you let everything go in one long stream.
The special thing is that you do not need to learn this pattern. Your body performs it by itself, regularly, even if you do not notice. It happens in your sleep. It happens after a good cry, where the sobbing is exactly that double in-breath. And it happens after a difficult conversation, when you sigh deeply without thinking and notice something settle. So the exercise is not a new technique but an existing reflex, used consciously at the moment you need it.
It is known as the physiological sigh, and you will also come across it as cyclic sighing or the double inhale. Behind all those names is the same pattern.
Deep in your lungs are millions of tiny air sacs, the alveoli. That is where your blood exchanges oxygen and carbon dioxide. If you breathe shallowly for a while, which happens as soon as you are tense or sit still behind a screen for long, some of those sacs collapse. They stick shut, as it were. The space where the exchange takes place becomes smaller, and more carbon dioxide stays behind than is comfortable. That contributes to that stifled, rushed feeling.
An ordinary deep in-breath only partly opens those collapsed sacs. The second, short in-breath does: it comes on top of lungs that are already full and pushes the last sacs open. Only then does a long out-breath really make sense, because then you release a lot of carbon dioxide in one go.
Then there is the pace. A long, complete out-breath naturally brings you to a slow breathing pace, close to six breaths a minute, and at that pace your heart rate drops. Your autonomic nervous system has two modes: an active, alert mode and a calm, recovering mode. The vagus nerve, the long nerve connecting your brainstem to your heart, lungs and gut, is the route that second mode runs along. Slow breathing is the simplest way to get there.
In short: the double in-breath makes room, the long out-breath uses that room.
1. Breathe in through your nose, calmly and fully, for about three counts.
2. Add a little more, a short extra sip through your nose on top of the first, for about two counts.
3. Breathe out slowly through your mouth, until your lungs are really empty. Take plenty of time for it, about seven counts.
Then take one normal breath, and repeat the whole thing two or three times. Sit or stand upright, with your shoulders low. The counts are a guideline, not a competition: if the second sip feels forced, the first was already too full.
It sounds simpler than it feels the first few times. Most people take a maximum breath straight away at step 1, so there is no room left for step 2. So make that first in-breath a little fuller than normal, but not to the brim. Then there is room for the small extra that does the work.
Sit upright, let your shoulders drop.
There are two ways to use it, and they ask something different of you.
The first is acute. You notice you are getting rushed, you are irritated after a message, you are about to do something you are dreading. Two or three sighs and you are approachable again. This is where the exercise excels: it needs no preparation, takes half a minute and you can do it while waiting in line or sitting at your desk. Nobody has to see it.
The second is daily. Then you do the pattern calmly for a fixed five minutes a day, regardless of whether you are tense at that moment. That is a different goal: not flattening a spike, but getting your nervous system used to switching back faster. For most people a fixed moment works better than a good intention, for example right after getting up or at the end of your working day.
Looking for something else? Then another exercise makes more sense. Want to stay calm and sharp at the same time, for example right before a presentation? Look at box breathing. Want to switch off and fall asleep more easily? Then 4-7-8 breathing fits better. Want to improve your basic pattern so you breathe more calmly all day? Start with practising belly breathing. An overview of techniques for tense moments is in breathing exercises for stress.
The physiological sigh has received attention in recent years thanks to a 2023 Stanford study (Balban et al., Cell Reports Medicine). Just over a hundred participants did a breathing exercise or a meditation for five minutes a day for four weeks. The four forms were compared side by side: cyclic sighing, box breathing, a faster form of breathing, and mindfulness meditation.
In that study all four forms improved mood and lowered tension. Cyclic sighing came out best on mood, and the breathing rate of that group dropped the most. The effect also grew the longer people kept it up, which matches what I see in practice: in the first week you notice something, after three weeks you notice the difference even at moments when you are not practising.
Two caveats belong with this. It is a single study with a limited number of participants, so it is an indication rather than an established fact. And the study looked at five minutes a day over four weeks, not at what a single sigh does in a single moment. The latter is what people most often read into it, and it is exactly what was not measured.
Ada is the breath coach of De Adempauze on WhatsApp. She sends you a short, tailored breathing session every day, the physiological sigh and other techniques, exactly when it suits you. Two weeks free, no obligations. Ada only speaks Dutch for now, but will be speaking English soon.
Do your first breathing session nowThe most common mistake is already mentioned above: making the first in-breath too full, so there is no room left for the second. Make the first generous but not maximal.
The second mistake is letting go of the out-breath too early. Many people blow out forcefully for a few counts and then stop, while there is still air left. It is precisely the last part that counts, because that is the air that has been standing still the longest. Let it go until you are really empty, without pushing.
The third is wanting too many in a row. Five, ten, fifteen sighs in a row is not a faster version of the effect. It can make you light-headed, and that is exactly the feeling you wanted to get rid of. Two or three is enough, with normal breaths in between.
And finally: do not expect your head to be empty afterwards. What changes is the sharpness of the moment. The thoughts are still there; they are just less insistent. That is enough to make a different choice than you would have made a minute earlier.
A sigh at the right moment helps you through that moment. The gain that lasts lies in repetition. If you practise for a few minutes a day, your nervous system gets used to moving to calm mode faster, and after a few weeks you notice that in tense moments you think of your breathing sooner. That is the real goal: not an emergency measure, but a habit that makes your days calmer.
That is exactly where it gets stuck for most people. Not on the technique, which you can learn in a minute, but on remembering. That is why De Adempauze works with daily guidance rather than a one-off explanation: Ada sends you a short exercise via WhatsApp every day that suits how you are doing, and you practise along in the practice room, where the circle sets the rhythm for you. Ada and the practice room are in Dutch for now, and will be in English soon. You can read the background of the approach on the page about the method. Rather practise with someone who watches along? Read how stress coaching works.
The physiological sigh is two in-breaths through your nose in a row, the second short and on top of the first, followed by one long, complete out-breath through your mouth. Your body does this by itself, in your sleep and after an emotional moment. As an exercise you consciously do what your body already does naturally, which makes it the fastest breathing exercise for a spike of tension or irritation.
In an acute moment, two or three sighs are enough. More rarely adds anything and can make you feel light-headed. If you want it as a daily exercise, choose a fixed five minutes a day and repeat the pattern calmly. Keep a normal breath between the sighs and do not rush the pace.
When you simply breathe deeply, you take a full breath and blow it out again. In the physiological sigh you add a little more air at the end of the in-breath. That second sip reopens air sacs that partly collapsed during shallow breathing, so the long out-breath afterwards releases more carbon dioxide in one go. So the difference lies in that second, short in-breath.
In two minutes you breathe yourself calm. A short breathing session every day via WhatsApp, tailored and at your moment. The physiological sigh and more, no obligations. Ada only speaks Dutch for now, but will be speaking English soon.
Do your first breathing session now