Kiwi William Trubridge put himself on autopilot and used yoga techniques as he free-dived to a new world record of 100 metres in the Bahamas.

The 30-year-old dived unassisted to reach the mark set in 1980 by Jacques Mayol, whose exploits were featured in the film The Big Blue.

But whereas Mayol used a weighted sled to descend and an inflated lift bag to return to the surface. Trubridge relied on his hands and feet to propel him through the depths.

After breaking the 100m record yesterday – and his own record of 95m – he said that he did not remember much of his dive, as he had been on autopilot throughout.

"I'm doing that more and more," he said.

"It's the same as driving or washing the dishes, it becomes part of your muscle memory, your subconscious. It means more efficient movements and with your brain out of action it uses less oxygen.

"A lot of my techniques are taken from yoga practice. My mother Linda is a yoga teacher and my wife Brittany has just become one too."

This was his 13th world record, but Trubridge, originally from Havelock North, said there was more pressure put on him during the latest record-breaking attempt.

"The earlier dives were part of competitions but this was a stand-alone event and everyone was there to watch. That raises the ante a little bit."

Additional pressure came his linking of the attempt to reach the 100m mark – one hectometre – with a campaign to help save the endangered hector's dolphin.

Only about 100 North Island hector's dolphins, also known as maui dolphins, remain.

He is using the publicity from his new record to try to put pressure on the Government to increase its protection of the dolphin.

He is also raising funds to help protect the dolphins by selling off one-metre lengths of the dive rope – a safety measure if needed – used in the record dive.

"That's going well, there's only 28 metres left," he said. Bids for the rope can be made through the Vertical Blue website.

Trubridge is not planning any attempt to extend his unassisted record in the near future.

"A hundred metres is kind of a nice round number," he said. "It kind of makes it more like a momentous achievement."

However, he is interested in trying to break the record for free-diving with fins, which stands at 124m.

He also wants to see if he can interact with hector's dolphins when he returns to New Zealand in January. "I'd love to swim with them."

- © Fairfax NZ News