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Two weeks ago, champion New Zealand freediver William Trubridge lost his sight and hallucinated in a dive he thought was about to claim his life.
But yesterday the 27-year-old elite sportsman took to the depths again, breaking a world record by diving unaided to a depth of 84m. The dive, part of the Vertical Blue competition involving 16 of the world's best freedivers, took three minutes 20 seconds.
Speaking to the Herald on Sunday from his home in the Bahamas just hours after his victory, Trubridge said yesterday's dive was "thrilling" - especially after his experiences a fortnight ago.
The former geneticist, who took up freediving only five years ago, had then attempted a "free immersion" dive, which involved pulling himself down a line to an extreme depth before being pulled back up. It resulted in severe narcosis, or a state of stupor, in which he lost all vision.
"I started hallucinating on top of that, then as I was towards the end of the ascent I saw a white light come in," he said. "I kind of interpreted that as the white light you see just before you die."
Trubridge, the son of renowned New Zealand artist David Trubridge, recovered sufficiently for yesterday's record attempt.
The previous unassisted dive record was held by an Austrian who dived 83m last year in Egypt.
The extreme sport of free diving is growing in popularity. Trubridge says it is as much a mental as a physical discipline.
"In your mind when you are thinking you need a significant amount of oxygen, you have to limit your thoughts. Thinking can sometimes lead to negative thought patterns which stress you out, accelerate your heart and increase your oxygen intake," he says.
It can, however, be a pleasurable experience. "You can sometimes get a high. It has a narcotic effect from the incredible concentration of gases, carbon dioxide and nitrogen. It can be scary but it can be quite euphoric.
"You need to have really flexible lungs," he says. "Because the deeper you go the more your lungs feel crushed."
Trubridge grew up on boats - his family sailed from Europe to New Zealand. "We were always in the water snorkelling, spending most of the day in the water. I guess it's kind of in me from the start."
Currently based in the Caribbean, where he teaches diving, Trubridge has plans to break more world records. Next week he will again attempt the free immersion record dive.
"This is the only sport that totally satisfies me. I did a bit of rowing. That was very physical but there was no mental side to it. I also played chess competitively and that was very psychological.
"Free diving combines the two - it's a great balance between the mental aspect and the physical."