Stress-relief breathing: the 5-minute exercise to know before an exam or a competition

Why breathing affects stress

Stress is driven by your autonomic nervous system, the one that runs your heart, digestion and sweating without you thinking about it. It has two main branches: the sympathetic system, the accelerator (“fight or flight”), and the parasympathetic system, the brake (rest, recovery). Before an exam or a competition, the accelerator takes over: racing heart, shallow breathing, tense muscles.

Breathing has one special feature: it's the only automatic function you can also control at will. And it's directly linked to your heart. When you breathe in, your heart rate speeds up slightly; when you breathe out, it slows down. By lengthening your exhale and slowing your pace, you press the brake.

A systematic review published in 2018 pulled together the studies on slow breathing (fewer than ten breaths per minute): it is associated with greater parasympathetic activity, better heart rate variability and, in terms of how people feel, more calm, alertness and comfort, with less anxiety¹.

The anti-stress breathing exercise, step by step

Here's the simplest version, to do sitting down, standing in a hallway or on a locker-room bench. It takes five minutes.

1. Get settled. Back straight but not stiff, shoulders relaxed, jaw loose. If you can, put one hand on your belly.
2. Breathe in through your nose for about 4 seconds, letting your belly rise rather than your chest.
3. Breathe out slowly for about 6 seconds, through slightly parted lips or through your nose, as if you were blowing on a candle without putting it out.
4. Keep going without forcing, at this pace of about six breaths per minute. No holding your breath with full lungs.
5. Bring your attention back to your breath every time it drifts toward what's coming. It's normal for it to drift: the work is to come back.
6. After five minutes, go back to normal breathing and rate how you feel, from 1 to 10.

If 4 and 6 seconds feel too long at first, start with 3 and 5: what matters is that your exhale is longer than your inhale and that the pace stays comfortable.

What about cardiac coherence?

Cardiac coherence is a particular form of slow breathing, close to what is often called “coherent breathing” in English and very popular in France as the “365 method”: 3 times a day, 6 breaths per minute, for 5 minutes (5 seconds in, 5 seconds out).

The pace of six breaths per minute wasn't chosen at random. In most adults, it's around this rate that the oscillations of the heart and those of blood pressure synchronize and grow larger: heart rate variability is then at its highest. This “resonance frequency” phenomenon is well described by researchers Paul Lehrer and Richard Gevirtz².

Let's be honest: the “365” rule is a practical recommendation to build a habit, not a protocol validated as is. What counts is practicing slow breathing regularly. If 5-5 suits you better than 4-6, stick with it.

The “physiological sigh”: the express version

Only have ten seconds before walking into the exam room or stepping onto the tatami? Try the physiological sigh:

1. Breathe in through your nose.
2. Without breathing out, take a second, shorter breath in through your nose to fill your lungs completely.
3. Breathe out very slowly through your mouth, all the way.

One to three rounds are often enough to release tension. In a 2023 trial where volunteers practiced five minutes a day for a month, this breathing centered on a long exhale (“cyclic sighing”) improved mood more and slowed resting breathing rate more than mindfulness meditation did³.

When to use anti-stress breathing

• Every day, for a few minutes: that's your training. A skill practiced when you're calm becomes automatic on the day the pressure rises.
• On the morning of an exam, after breakfast, or on your commute.
• Right before you walk into the exam room or give your oral presentation: two or three physiological sighs.
• During the exam, discreetly: three long exhales through your nose if you get stuck.
• Before a competition, during your warm-up or between two rounds, like mokusō in karate (see our guide to mental preparation in karate).
• In the evening, to fall asleep when your mind is still racing.

Common mistakes

Breathing too hard

Breathing slowly doesn't mean breathing a lot. Big, forced breaths taken too close together can cause dizziness or tingling (hyperventilation). Your breathing should stay gentle, almost silent.

Trying to force yourself to be calm

If you do the exercise while telling yourself “I absolutely have to calm down right now,” you add pressure. Just follow the rhythm: calm comes as a consequence, not as a goal.

Only trying it on the big day

Discovering a technique on the morning of the exam is like trying on new shoes on marathon day. Practice a few days before, so the skill feels familiar.

Apex's Kiai: guided breathing

In Apex Mindset, breathing is one of the four steps of the Express Protocol: the Kiai, a guided breath to relax your shoulders and jaw, preceded by anchoring (Mokusō) and followed by mental rehearsal (Kata). The rhythm is shown on screen: you have nothing to count, just follow along. You rate your stress before and after, so you can see the effect on you instead of taking our word for it.

To know what to do the day before and the day of an exam, also read our 7 steps against exam stress.