Meet The Freediver Who Smashed The 100m Barrier

William Trubridge is a true pioneer who became the first person to dive unassisted through the 100m barrier, on a single breath of air

Freediving is a fascinating sport – the idea that an air-breathing human could even survive to swim 100m deep, under pressure ten times that of the surface and on a single breath, is hard to comprehend. When you consider that New Zealander William Trubridge backed his physical ability to swim back up again, as well as his mental ability to hold panic and the rising desire to breathe at bay, for four minutes 14 seconds, you start to see what it took for him to break 100m. What can we learn from his steely cool?



With Jennifer Lawrence and James Cameron currently working on a movie about the sport of freediving, it’s a good time to look into this mysterious world… Put your face into cold water and a funny thing happens: rather than panicking your heart rate into overdrive, it actually starts to drop. It’s down to something called the mammalian dive reflex, which it seems humans share with dolphins and other marine mammals. Dive deeper – on a single lungful of air – and a blood-shift occurs, sending oxygen away from our limbs and to our vital organs and brain. Dive even deeper and the spleen contracts, pushing a ‘reserve tank’ of oxygen-rich blood into the bloodstream. If it were not for freedivers like William Trubridge, pushing the limits of human survival, scientists would never have become aware of these extreme capabilities, which we all share. That might help explain why Trubridge spent two years training to dive past 100m, unassisted, with no fins and on a single breath. It sounds hard but it’s even harder than you think, because deeper than about 10m you become negatively buoyant – stop swimming up and you immediately start sinking, basically.

So, swimming back to the surface becomes bloody hard work, especially on a single breath, clawing your way with hands and feet as gravity attempts to pull you down to Davey Jones’s Locker, with rescue only possible once you’re within the range of safety divers at 30-35m. Maintaining a zen-like level of calm, as well as a super-efficient stroke, becomes essential for survival. In 2014 Trubridge fell short of that, 10m from the surface, and had to be swum to safety by the divers.


RISING You also set a record of diving to 120m in 2016 – how was the unassisted one different?

William Trubridge ‘The record was to 102m unassisted. The other record was for free immersion where you use the rope to pull yourself down, and up, so you can get to a deeper depth. This record was to 102m in the no-fins discipline, which is the purest form of freediving because you don’t have any propulsive assistance – it’s just your body moving through the water.’


‘I’m not so good at static breath holds – the longest I have done is 8 minutes – it was pretty difficult’


RISING What is the most challenging thing about being the first human to break the 100m barrier?

WT ‘The main challenge is just being at great depth and not having a way to return to the surface with a lot of propulsion. It’s not like swimming in a pool where you can kick, or take a stroke and glide – as soon as you stop swimming you stop moving and start sinking again. That can be a bit disconcerting at first. The main thing is just to move as efficiently through the water as possible.’


RISING You’ve said that the key to your success is staying present in the moment during a dive to calm your mind, and not think about how deep you are – how do you do this?

WT ‘So, rather than thinking about those things then I just focus on technique. I’m emptying my mind and not thinking about anything at all. A halfway measure would be to give the brain a menial task, which doesn’t use any mental energy, such as counting my strokes – I take a stroke about every four seconds on the ascent so I often count those. It’s a very very slow rhythm, so if I’m counting those strokes then it slows my mind down as well. 1…. and….. 2…. and….’


RISING You train breath holding statically too – what’s the challenge there and how long can you hold your breath for?

WT ‘When you start out breath holding it’s about finding relaxation in that state of urgency that comes with the urge to breathe. I’m not so good at static breath holds – the longest I have done is 8 minutes. It was pretty difficult.’


RISING You must have to be super-confident in your athletic ability – you do any specific swimming training?

WT ‘Through training I’ve created the right stroke technique and timing for swimming, and that happens spontaneously. There are a lot of different areas of training that have to be worked on: technique at the pool or resistance to high CO2, low O2 levels; flexibility is important especially in the chest, ribs and diaphragm. Then, if you have a more powerful stroke that’s also more oxygen efficient, you’re going to be getting the maximum power.’


RISING You’ve said before that you get into the athlete’s ‘flow state’ in order to dive deep – how do you do this?

WT ‘The more you train and program muscle memory, the more it becomes subconscious and automatic. Also the narcosis, the high pressure of nitrogen and carbon dioxide help to take the edge off and slow the mind down more. So it’s a combination of repetition and the effects of the pressure, that makes getting into flow state easier.’


‘As soon as you stop swimming, you stop moving and start sinking – that can be a bit disconcerting’


RISING You’re the first to smash the 100m barrier – how deep do you think humans could go?

WT ‘New depths will come and it will be a more organic process. For now the deepest unassisted dive is 102m. If I was to say that the human limit is 105m then I might reach that but no deeper, because that would become a mental block for me. For now I’m focussed on my own career and the campaigns that I support, the state of the oceans, the species on the verge of extinction and the amount of plastic that we’re putting into those ecosystems.’


RISING Do you ever get a sense on a dive that things aren’t going to plan?

WT ‘On a bad dive the descent would be similar to a good one – but somewhere towards the end of the descent, or start of the ascent, I would start to get an awareness that it’s not going to be an easy dive. And, that feeling might intensify on the way up to the point where I instinctively realise that it’s definitely going to be bad – then I will abort the dive, and I do that by starting to pull on the rope, which makes the ascent easier.’


RISING What about a good dive – how does that feel?

WT ‘On the perfect dive, on the way down, I would be totally concentrated, relaxed, being able to empty my mind and feeling very peaceful on the descent. At the turn I would still have an empty mind and it’s about then, at the turn or soon after, that I begin to get an instinctive awareness that the dive is going to be good, or easy. Breaking the surface would be sensations of joy, exhilaration, relief and happiness.’


RISING Explain why the most dangerous point of a dive is close to the surface?

WT ‘If you imagine a breath hold, then you’re lowest in oxygen at the end of the dive, as you approach the surface. You’re not going to have low oxygen at the lowest point of the dive, unless you have really overestimated yourself. You should still have half of your oxygen left. The safety divers come to 30-35m and that’s more than adequate – I have never had a problem deeper than 10m and I have only had a problem beneath the surface on a couple of occasions.’


RISING You’ve said in the past that narcosis at depth has made you clearly see lights and human faces in front of you. What do you normally see down there – it must be very dark?

WT ‘In the open ocean even at 100m there would be plenty of light but Dean's Blue Hole [in the Bahamas] tends to swallow the light. For most of the dive I can only see the line in front of my face, and that’s it. On the way down I mostly have my eyes closed. I open them every few seconds to check my position against the line to make sure I’m falling straight. On the way up I have them open more. For a competition there are lights at the base plate, but you only see those when you are very close to it. If the conditions are bad, then I will wear a little head light so that I can still see the line at depth.’


RISING You’re a World Record holder but is that the only reason you dive? What’s the appeal?

WT ‘We spend all of our lives in air – we hardly ever move through liquid and freediving allows us that opportunity. And it’s the purest measure of human aquatic potential. Aside from that the reasons I freedive are to do with the sheer pleasure and enjoyment of being underwater and the escape from the life above the surface. It’s a very different sensation – it isn’t something we come across in our everyday lives.’



WHAT NEXT? In order to get an idea of the challenge Trubridge bested, watch his full record breaking attempt online. You might want to sit and try a static breath hold from the moment he dives, and see where you get to – just make sure there is someone on hand to catch you if you faint!