Breathing safely
Most of the techniques in ALISI are as safe as sitting still. The retention rounds are not, and they are the reason this page exists.
Why breath retention needs care
The urge to breathe is triggered by rising carbon dioxide, not by falling oxygen. Breathing quickly for a minute or two flushes carbon dioxide out of your blood, so when you then hold your breath the alarm does not go off — while your oxygen keeps dropping. You can lose consciousness without ever feeling short of breath first.
On dry land, sitting or lying down, a blackout is frightening but usually harmless: you pass out, you start breathing again, you come round. In water it drowns you. Swimmers and freedivers have died doing exactly this, which is why every water-safety body warns against hyperventilating before a breath hold.
The rules, every time
Never in or near water
Do not practise this in a pool, the sea, a bath, a shower, or anywhere you could fall into water. Breath holding after fast breathing can make you black out with no warning and no urge to breathe first. People have drowned this way.
Sit or lie down
Fainting is a real possibility. Practise seated or lying down, somewhere you cannot hit anything on the way down. Never standing.
Not while driving
Do not practise while driving, cycling, swimming, or operating machinery — including as a passenger about to take over.
Check the health questions first
Breath holding is not suitable for everyone. Answer a few health questions once, and talk to a doctor before starting if any of them apply to you.
Stop if it feels wrong
Tingling, lightheadedness and tightness in the hands are common and pass on their own. Chest pain, a pounding or irregular heartbeat, severe headache, confusion or feeling faint are not — stop, breathe normally, and seek medical advice.
Do not practise breath retention if…
Talk to a doctor first. The calming techniques — coherent breathing, extended exhale, the physiological sigh — involve no breath holding and are a better starting point.
- I am pregnant. Breath retention and hyperventilation are not recommended during pregnancy.
- I have a heart condition or have had a stroke. Includes arrhythmia, coronary artery disease, heart failure and prior stroke or TIA.
- I have epilepsy or a history of seizures. Hyperventilation is a recognised seizure trigger.
- I faint easily or have fainted before. Breath retention after fast breathing can cause loss of consciousness.
Take extra care if…
- I have high blood pressure that is not well controlled. Speak to your doctor before practising breath retention.
- I have asthma, COPD or another lung condition. Keep your reliever inhaler to hand and stop at the first sign of tightness.
- I experience panic attacks. Fast breathing can bring on the physical sensations of panic. Start with the calming techniques instead.
- I have had surgery in the last three months. Check with the team who treated you before doing breath holds.
Normal, and passes
- Tingling in the hands, feet or face
- Lightheadedness or a floating feeling
- Tightness or cramping in the hands
- Feeling warm, or a wave of emotion
Stop immediately
- Chest pain or pressure
- A pounding, racing or irregular heartbeat
- A severe or sudden headache
- Confusion, or trouble speaking or seeing
- Feeling like you are about to faint
Alisi is a wellbeing app, not a medical device, and nothing in it is medical advice. It does not diagnose, treat or prevent any condition. If you have a health condition, are pregnant, or are unsure whether these exercises are right for you, speak to a doctor first. If you feel unwell, stop. In an emergency, call your local emergency number.