Breathing exercises for stress: three, and you are in charge.

There are three breathing exercises for stress worth learning: the double sigh, the counted breath out and belly breathing. They all work the same way, through a long breath out: when you make it longer, your heart slows down. The shortest one takes 30 seconds.

By the third meeting your breathing is already short and high up, and you do not notice it. I see it often in the business owners I work with: they look for another coffee, when the fastest tool is already in their body.

How do you know if you are breathing badly under pressure?

Put one hand on your belly and sit still. If it does not move when you breathe in, you are breathing high up, with your neck and shoulders. It is very common and not an illness.

• Your belly stays still. You breathe in and your chest, collarbones and shoulders lift.
• Your breathing is short and jerky. Sometimes you hold your breath without noticing.
• You breathe through your mouth. Your nose filters, warms and moistens the air.

Why do breathing exercises calm stress down?

Because breathing out reaches the pacemaker of your heart. It is the only voluntary route into a system that otherwise runs on its own.

Breathing out slows you down, breathing in speeds you up. A long or strong breath in raises your heart rate. A long breath out lowers it: it touches a fibre of the vagus nerve that slows that pacemaker down. That is why "take a deep breath" is the wrong advice.

The two breaths in both matter. Inside your lungs there are hundreds of millions of tiny air sacs, the alveoli, and under tension they stay stuck together. The first breath fills many; the second, short one reopens the rest. Through the nose is better: the air meets more resistance.

You do it more than 20,000 times a day. At rest you breathe about 15 times a minute and move 8 litres of air; under stress you reach 200 litres. The diaphragm is the first muscle that tension blocks.

The three exercises: how to do them, and when they do not work

The double sigh: 30 seconds, as soon as you put the phone down. Breathe in through your nose twice, with the second one short, then breathe out slowly through your mouth until your lungs are empty. Do it one to three times, and often the first is enough. Your body already does this cycle by itself, even while you sleep.

The counted breath out: two minutes, in the car before you walk in. Sit with your back straight but not stiff. Breathe in slowly through your nose for 4 seconds, filling your belly first. Add a short breath into your chest for 1 second, then breathe out through your mouth for 8 seconds. One round is about 13 seconds: 5 to 10 rounds and you drop from 15 breaths a minute to four or five.

Belly breathing: two minutes, in bed at night. Lie down, one hand on your chest and one on your belly: as you breathe in, only the lower hand should move. If you cannot, put a book on your belly and try to lift it.

The mistake almost everyone makes: pushing the belly out all day. Belly breathing builds awareness, it is not a rule for ever. Standing and moving, you need the other one: the breath that widens your ribs sideways.

When they do not work. If you breathe a lot and fast you blow off too much carbon dioxide and end up worse: dizziness, confusion, restlessness. And if your body is loaded with energy, breathing alone is not enough: first you burn it off by moving. I explain how in the article on calming down quickly.

A breathing exercise is not a retreat practice: it is a mechanical lever that works even if you do not believe in it. Learn it while you are calm, before you need it.