Learning to breathe
The fine art of free diving
FREEDIVING HAS ALWAYS seemed to me one of those sports that belong in the same category as wingsuiting; death or injury appears a matter of when, not if. Scuba diving to a hundred metres is loco enough, but doing it sans tank, with only a lungful of air, well that, my friends, seems certifiably insane.
Which is why I felt so weird that on my first freediving session. There I was, far below the surface, deeper than I’d ever dived, and I was feeling not pumped with adrenaline but instead so comfortable I felt I was in a womb. A baby-blue womb of sloshy amniotic fluid, all soft and protective where I could just float and relax. I’d stopped descending at this stage. Hitting the end of the 12m rope that had been set up, I was in no hurry to ascend, so I’d decided to sit and wait until I began running out of breath. The curious thing was that this didn’t happen; the urge to breathe, it seemed, had simply disappeared. I sat there looking up at the soft light beaming down from above, examining the spidery shapes of my fellow freedivers, way, way up there on the surface. And I meditated.
Not consciously chanting mantras or deliberately trying to clear my mind, but there’s no better way to describe the peace and stillness I felt other than to say it was meditative.
That first day of freediving took place in the tropical blue waters on a small island off the coast of Indonesia’s Lombok called Gili Trawangan, and I was there with instructor Mike Board, along with three other pupils learning the basics of the sport. Just a couple of days earlier I’d been snorkelling around the spectacular coral of nearby Gili Air, and swimming with sea turtles and schools of tropical fish that sparkled like glittering confetti. Most of my outings were towards the island’s northern end, away from other snorkelers. But two days earlier I shared the waters with a spear fisherman, and I watched him working the coral wall. Damned if he couldn’t stay down there. And damned if I didn’t want to, too. It is, of course, the very reason so many snorkelers progress to scuba diving.
But there’s something about scuba diving that’s never quite captured my interest. Tanks, nitrox, regulators, gauges – it just seems so equipment heavy. Instead, I like the simple purity of just filling your lungs and going for it. So I’ve always stuck with snorkelling. Freediving seemed just as pure, only it took it to another level. That I liked, too. It took skill. Physical skill. It even had, unlike scuba, a competitive element. Go longer. Deeper. Harder. Oooh baby.
And yes, I admit it, there’s another factor; I am a tightarse.
Having never liked the idea of continually hiring scuba equipment, the free in freediving held double appeal: minimal equipment, and—once I’d purchased my snorkel, fins and mask—diving without the further outlay of even one brass razoo. But it had never occurred to me there might be an actual school out there teaching you how to do it, let alone instructing you how to not die in the process. But watching the deeplunged spear fisherman jogged my memory of a freediving school on the island next door run by Board—a Britisher who holds four national freediving records as well as an unofficial descent to 103 metres. That evening, I sought him out.
HOW NOT TO DIE
I won’t bore you with all the details regarding each dive I did, nor prattle on about the kaleidoscopic experience of seeing brightly coloured fish and extravagant coral in the warm tropical waters, but I will impart what I learnt from attending Board’s freediving course.
As well as learning how not to die, I also learnt more about science and human physiology in two days here than in a year of high school science. The Respiratory System! Capillarisation! Cerebral vasoconstriction! Eustachian Tubes! Boyle’s Law! The Law of Partial Pressures! All that useless stuff that back then bored me to tears—you know, facts—now seemed riveting.
I was fascinated to learn, for example, that it’s not actually lack of oxygen that makes you want to breathe; it’s CO2 buildup. To learn that
Unlike scuba, there are no issues with nitrogen and decompression sickness. And in organised freediving competitions there has never been a fatality.
humans, like dolphins and seals, can use the mammalian dive reflex to stay underwater longer. To learn that hyperventilating is not only dangerous, it makes your ability to stay down far shorter. But these I’ll get to later.
Importantly, I also learnt that freediving is, or at least can be if the correct procedures are followed, surprisingly safe. True, Board’s demeanour – calm, considered, confident – could convince you anything is safe. The crisply accented Englishman oozed such confidence that within minutes of meeting him I’d decided he was a man I could trust with my life. Only later did I discover that Board’s life path to becoming a freedive instructor included six years in the Royal Marines, followed by years as a diplomatic security consultant in Israel, Palestine, Baghdad and on the Georgian-Chechen border.
Unlike scuba, there are no issues with nitrogen and decompression sickness. And in organised freediving competitions there has been just one fatality. That’s not to say others don’t die. By some reckonings, freediving ranks only after base-jumping in terms of deaths, although those figures include spearfishing. Blackouts are the most common cause.
But Board insists blackouts themselves are not dangerous. “They’re no more harmful to you than fainting. Essentially you pass out; you continue breathing and when enough oxygen returns into your system, you wake up. There is no damage at all. You still have minutes until the flow of oxygen stops. And then you have several minutes again until any brain damage occurs.”
At least, this is the case on dry land. In the water, though, it is different. When you pass out, your brain recognises there is water by the airways, so you continue to not breathe. Without oxygen, the brain begins to suffocate, to the point it can no longer send the signal to not breathe. Your airways open up. Now you begin taking in water.
You are fucked.
Unless you are with someone.
Which you are, right? Because this is the golden law of freediving. Without someone to rescue you, a blackout will kill you. Guaranteed. With someone, you will be safe. Virtually guaranteed. The reason is that nearly all blackouts are at or near the surface, where your partner can easily rescue you.
Pressure is the villain and saviour here, a two-edged sword that makes freediving both dangerous and safe. Well, at least safer. The dangerous bit is easy to understand; every 10m of underwater descent increases the pressure by one atmosphere. Your ears, at least, can be equalised to deal with the increasing pressure. The key is to equalise often and, crucially, early. “Don’t be stingy with it,” says Board. “Don’t wait until you feel the pressure build; begin equalising even in the first few metres underwater.”
What you cannot equalise, however, are your lungs. And what Boyle’s Law – which to refresh your memory is simply that gas volume decreases proportionally with increasing pressure – means for your lungs is this: at 10m, they are already half their usual size. At 30, a quarter. A hundred metres below the surface – and the very best freedivers can get deeper still – and the average male’s six-litre lungs have shrunk to the size of a pair of oranges. Lung squeeze is a very real danger for freedivers.
But shrunken lungs allow you to, for want of a better way of putting it, squeeze the oxygen out of them. It’s as they expand that it becomes harder. And the greatest expansion, and hence most blackouts, occurs not at depth but where the greatest pressure differential lies – the upper 10m, and in particular, at the surface. Precisely where you can be rescued.
“I’ve only ever seen blackouts below the surface in competitions,” Board assures us. “And even in competitions, the deepest safety divers only go to 50m.”
“But what happens if you get narcosis at 80m, and you’re off with the fairies?” asks one of the other students, Paul, a pilot now based in Hong Kong.
“Well,” replies Board, without a trace of emotion, “that can be a problem.”
THE SCIENCE OF BREATHING
Perhaps it is strange that competitive breathing has never taken off as a sport. Breathing is, after all, our most fundamental activity. Not running. Or eating. Or even procreating. Without breath, we each have just minutes to live. But while we have all manner of sports testing physical skills with varying levels of contrivance, very few sports actually test our ability to take in a lungful of air.
Breathing, Board explains to us—as we listen in our open air classroom to the wail of the muezzin, the jingle of passing horse carts, the crack of thunder and the pattering of rain—works like this: we inhale oxygen, which moves down our bronchial tubes, into the alveoli in the lungs.
The membrane in the alveoli is extremely thin, just a few cells thick. The oxygen moves from high pressure to low pressure, through the capillaries and in the process it bonds to the haemoglobin in the blood. This then travels throughout the body. The vein network then returns the blood, now with CO2, back to the heart and then the lungs.
It’s this CO2 – which is a metabolic toxin – that triggers the urge to breathe. “Your body doesn’t mind being low on oxygen, funnily enough,” says Board. “It’s the CO2 it wants to get rid of.” The medulla—where the brainstem connects with the spinal cord, and which controls respiratory and cardiac functions, along with sneezing, vomiting and other fun involuntary bodily functions—detects changes in the pH. It sends a message for you to exhale, to release the increased amounts of CO2.
Given the importance of the awareness of breath, it’s perhaps unsurprising that our breathing lessons commence not in the classroom or in the water, but instead in the yoga hall. I had never considered a connection between the two but, of course, both are heavily focussed on breathing, and the relationship is symbiotic enough that the school is actually 50:50 freedive and yoga.
For us though, Board has adapted a series of yoga manoeuvres focussed on stretching the thoracic area. He starts with Sufi grinding. Done by Board, it’s a kind of graceful swirling movement of the torso while seated; done by me it evolves into a motion not unlike a madman rocking backwards and forwards in an asylum. From there we move to spinal flexes, rotations, side bends and neck rolls. In sum, these are designed to warm up the spine and the muscles used for breathing.
The breathing exercises themselves follow. Again they are essentially yogic techniques. We commence with diaphragmatic breathing, which is breathing without moving your chest but instead letting your abdomen move in and out. Freedivers or yoga practitioners aren’t the
Relaxation is key to staying underwater longer. Your brain is a big consumer of oxygen; if you’re panicking, it uses more.
only ones to benefit from diaphragmatic breathing practice, however. We all can. With our sedentary, largely seated lifestyles, many of us breathe shallowly, through the chest. But studies have shown diaphragmatic breathing, at the very least, reduces stress. Others believe it can help with specific disorders, such as high blood pressure, insomnia and asthma.
Then we reach the heart of the matter; the art of filling your lungs. It’s not the breathing technique usually assumed; hyperventilation is not only dangerous, Board explains, it doesn’t work anyway. To demonstrate, he gets us to hyperventilate. We take 10 quick, heavy deep breaths. “How do you feel?” he asks. “Dizzy? Tingling?” We all nod. “Exactly!” Hyperventilating lowers your CO2 levels, which increases cerebral vasoconstriction and in turn decreases the blood flow to the brain. And it stops the mammalian dive reflex, which I’ll get to shortly, from kicking in.
No, the art of lung filling is not hyperventilation but two-section breathing.
You first fill slowly with the diaphragm, and only once it’s full do you then expand your chest, again slowly, to inhale as much air as possible. Learning the art of two-section breathing is important for freediving as they are the last breaths you take before diving. You take no more than four of these – it’s dangerous otherwise – and on the final one you fill your lungs and go for it.
“Your final breath should feel like you want to explode,” Board instructs us. “And don’t worry about getting too full; once you’re underwater, the pressure will stop you from feeling too stretched out.”
This technique of two-section breathing, and indeed yogic breathing in general, does more than simply fill the lungs; it triggers a deep state of relaxation. And relaxation is key to staying underwater longer. Your brain is a big consumer of oxygen; if you’re panicking, it uses more.
But to induce relaxation, breathing is just one of two key techniques; for the other, we need to board Board’s outrigger, sail past a gaudy flotilla of local fishing boats moored off the beach, and get in the water. The mammalian dive reflex is what allows aquatic mammals like seals, dolphins, otters and whales to stay underwater for long periods of time. But humans possess the mechanism too, albeit in a weaker form. The effect works best in cold water, and also the younger the person, which is why you sometimes hear stories of toddlers spending an inordinate time under freezing water and still surviving.
When your face is submerged and you stop breathing—which is why the effect works for freedivers but not scuba divers—water sensitive receptors around the nasal cavity and other parts of the face relay this information to the brain, and a number of physiological reactions take place. Your heart slows, thanks to process known as bradycardia, thus using less oxygen. Top freedivers, says Board, can slow their hearts
down 17 to 20 beats a minute. Your spleen contracts as well, releasing more red blood cells into the body.
Meanwhile, in a process known as vasoconstriction, the capillaries in your extremities – hands and feet, then arms and legs – get smaller. This leaves more blood for other essential organs, such as your heart, brain and lungs. And speaking of lungs, there is one last key element of the mammalian dive reflex, one that saves them from being crushed by deep dives. As your lungs reduce in volume because of increasing pressure, blood shifts to them and swells their blood vessels. This inhibits excessive compression, aka lung squeeze, and prevents barotrauma injuries that might otherwise occur at depth.
There is a side effect of all this: you feel really, really comfortable underwater. Blissful even. “It might take a few dives to induce this,” says Board. “It might even take 30 or 40 minutes. But after a while you’ll notice you’re feeling incredibly relaxed; that’s the mammalian dive reflex kicking in.”
Which brings me back the most surprising element of all of this. Relaxing under the water. Sitting still. Not moving. Watching the dancing sunlight play down in columns. Contemplating the seamless gradation from baby blue to darkening depths. Embracing the thick warmth of the water. But, most unexpectedly, letting the mammalian dive reflex embrace me. Down here, deeper than I’ve ever dived, I expected to find adrenaline; instead I discovered one of the most complete states of relaxation I’ve ever found.
A minute later I would be on the surface, having returned not because of a lack of air but because I’d been down so long it would seem prudent to do so. I would reach the surface so relaxed the need to draw breath would seem barely apparent. My lungs would not be heaving; one small inhalation and I would begin talking immediately.
But all this would be later. For now I sat. Sat far below. Meditating. And astounded that here of all places, I had found a soft blue peace.
It’s easy to laugh when you can dive 100m deep on a single breath. Freedive Gili co-founder Mike Board.
First things first: before we even jumped in the water, Board ran us through a sequence of yogainspired breathing and relaxation techniques.
Relaxing on the outrigger to the dive site.
Instructor Gary McGrath shares a laugh with students.
The soft blue peace of freediving.