The one rule: never train breath-holds in water alone. Not in the sea, not in a pool, not in the bath. Blackout can happen without warning, and in water it can kill. Dry training on land is fine with someone present. In the water, always have a trained buddy watching you, one up, one down.
People search this question for all sorts of reasons: surfers who want to survive a hold-down, spearfishers, swimmers, people who just want to snorkel down to the sea floor and look around. The answer is the same for all of them. You hold your breath longer by using less oxygen and by getting comfortable with the urge to breathe, safely. Toughness has very little to do with it.
Why you want to breathe
The urge to breathe does not come mainly from running out of oxygen. It comes from carbon dioxide building up in your blood. Your body is very sensitive to CO2, so the first discomfort arrives long before oxygen is anywhere near dangerously low.
That is useful to understand for two reasons.
First, the early urge to breathe is not an emergency. With training you learn to recognise it as a signal, stay relaxed through the first contractions of the diaphragm, and not panic.
Second, the warning system can be switched off, and that is dangerous. If you lower your CO2 artificially, you remove the signal while oxygen keeps falling. That is how people black out without ever feeling that they needed to breathe.
Relaxation is most of the work
Every tense muscle burns oxygen. A racing mind burns oxygen too. So the biggest improvement most people ever make comes from simply relaxing: loose shoulders, soft face, still body, slow heartbeat.
Freedivers also benefit from the mammalian dive reflex, a set of automatic responses that humans share with other air-breathing mammals. When your face is in cool water and you hold your breath, your heart rate tends to slow and blood is directed towards your vital organs. You do not need to do anything to trigger it except stay calm; stress works against it.
What helps
Breathe slowly before a hold
Before a breath-hold, breathe calmly and slowly for a couple of minutes, with a relaxed, longer exhale. Then take a full but comfortable last breath, without straining. That is the basis of everything we teach on land before anyone gets in the water.
Do not hyperventilate
Several fast, deep breaths before a hold is the most common mistake. It makes the first part of the hold feel easy by flushing out CO2, but it adds almost no extra oxygen. The result is a longer hold with no warning at the end of it. In the water, that is exactly how shallow water blackout happens.
Train dry, on land
The safe place to practise is lying down on a bed or a mat, on land, with someone nearby who knows what you are doing. Freedivers use simple tables:
- CO2 tables keep the breath-hold the same and shorten the rest between holds. They train you to stay relaxed with rising CO2.
- O2 tables keep the rest the same and lengthen the holds gradually. They build comfort with longer holds.
Keep the holds well within your comfort, stop at any sign of dizziness, tingling or tunnel vision, and never do tables in water, standing up or while driving, cycling or anywhere a sudden loss of consciousness could hurt you.
Improve your technique
In the water, a longer dive is often about wasting less rather than holding more: smooth finning, a streamlined body, good equalisation so you are not struggling on the way down. This is where coaching makes the biggest difference, because it is hard to see your own technique.
General fitness and routine
Regular aerobic exercise, good sleep and not diving tired or dehydrated all help. So does not eating a heavy meal just before training.
What does not help
- Pushing through warning signs. Tingling lips or fingers, dizziness, a strange calm or narrowing vision are signs to stop, not signs of progress.
- Competing with friends in the pool. Breath-hold contests in water are how people drown.
- Holding at depth for longer on your own. The most dangerous part of a dive is the last few metres of the ascent and the first seconds at the surface.
Shallow water blackout, in plain terms
Oxygen in your lungs is under more pressure at depth, which helps your body use it. As you swim back up, that pressure drops, and so does the oxygen available to your brain. If you have stayed too long, your oxygen can fall below the level needed to stay conscious in the last metres before the surface or just after you arrive. There is often no warning.
A blackout on land usually means you wake up after a moment. In the water, without someone there, it means drowning. That is why freedivers always dive in pairs: one diver goes down while the other watches from the surface, and stays watching for at least half a minute after the diver comes up and is breathing.
Taking it further, properly
If you want to go beyond a few calm breath-holds on land, learn with a qualified instructor. On our beginner courses, people typically reach two to three minutes of breath-hold and 10 to 20 m of depth over two to three days. It starts on land with breathing and relaxation, then continues in calm water on a line, with an instructor beside you and never more than four students per instructor. No experience is needed, but you should be comfortable in the water and able to swim about 200 m.
Most of our sessions take place at Schinaria Beach, east of Plakias. Read what freediving is for what a first session involves, the freediving gear guide for the equipment, and our courses and prices when you are ready. If you are visiting the area anyway, the Plakias guide from our partners at Scuba Diving Crete covers the rest of the trip.
This guide is general information, not medical advice. If you have any medical condition, speak to your doctor before you start breath-hold training.