Kiwi free diver William Trubridge has less than 36 hours to prepare for his "redemption".

With the heartbreak of a failed 2014 record attempt still in his mind, 102m of deep blue ocean is what stands between him and success.

And he is having to endure one of the toughest mental battles imaginable.

On the one hand, Trubridge must calm himself to a point where adrenaline becomes irrelevant. On the other, he feels the pressure of going for a new free diving world record.


"Just the weight of that, it weighs you down as much as the depth itself," Trubridge told the Herald from Bahamas.

"Mentally, you have to convince yourself you can do it."

In 2014, supporters from all around the globe tuned in to watch Trubridge come agonisingly close to the record. He needed assistance from his crew just metres from the top.

But now, Trubridge has more belief than ever.

"Where I am, mentally, has changed in a big way," he says.

"In my personal life, a few years ago there was some stuff going on which made it much more difficult.

"I've been able to gain a greater peace of mind going into this attempt and I think that will make a huge difference."

For those who are nescient to the nuiances of free diving, there are a number of different ways for a diver to descend into the darkness.

The free immersion method, which Trubridge got the record for last month, involves the diver pulling themselves up and down on a guide rope.

Another method allows divers to be aided by fins.

But the true challenge, and the ultimate test of composure and fitness, is the constant weight without fins.

No assistance, just the diver, his arms and feet, and his mind.

"It's definitely the hardest and I'm a sucker for a challenge," Trubridge says.

"I see it as the purest discipline and that motivates me as much as the record.

"It's just you. Your hands and feet. So you actually feel, with every stroke, the sensation of grasping the water and pulling yourself toward it and that can be a really magical feeling."

Trubridge has been training for this dive for the best part of a year, starting immediately after his sponsor, Steinlager, had finished with the Rugby World Cup.

Since then, he's been slowly but surely making his way down to the 102m mark and is poised to reach his goal early on Thursday morning (NZT).

And whether successful or not, Trubridge made one thing clear; he won't be retiring.

"I have great passion and drive to continue to go deeper," he said.

Trubridge will make his attempt at Dean's Blue Hole, the site where he makes most of his dives.

Viewers can tune in to TVNZ's Breakfast at 7.40am on Thursday morning to watch the attempt.