GOING for a swim is something many Australians take for granted.
Whether in the pool or the ocean, a dip on a hot day is a common ritual on this island continent of ours.
Not for Todd Sampson, though.
Open water is something that makes the man, who has climbed Mount Everest unassisted, quake in his boots.
"I don't have a phobia of water but I don't like it. I live in Bondi and I don't go to the beach," he tells Weekend.
"I learned to scuba dive because I'm scared of water. I thought that would habituate me, but it didn't. I breathe really fast and chew through my air."
So it's not surprising when Sampson says he was not at his most comfortable in scuba gear 20 metres below the surface in the warm clear waters of the coral triangle off Borneo.
"I was struggling to keep my buoyancy and cameras were all there filming me. I look like a frog underwater. But then suddenly this body shoots down with Facebook underwear on and nothing else. He dives straight to the bottom, looks at me with his handmade goggles, gives me a thumbs up and proceeds to walk on the bottom of the ocean floor for four minutes. That blew my mind."
The scene he describes was filmed as part of his new TV series Body Hack.
In the six-part documentary the father-of-two tries to unlock the secrets of some of the world's most extraordinary people, in this case freediving Bajau fisherman Sulbin.
He also spent two weeks training for his first MMA cage fight, lived with hunter gatherers in Tanzania, worked as a Bollywood stuntman and a Himalayan sherpa and pushed himself to the absolute limit both physically and mentally while training with the notorious French Foreign Legion deep in the Amazon jungle - all in the name of informative television.
"It's one thing to observe things when they happen but it's another when it happens to you," he says.
"Everything looks okay on paper but once you get there it's like 'wow this is not easy'."
Two years in the making, the series was not written for natural thriller-seekers and adventurers like Sampson.
"If they watch that's cool but I wrote it for mum sitting at home with the kids," he says. "It's a science show about human potential.
"I made it because I think there are interesting things to learn from it, not because I want to get punched in the face by an MMA fighter."
Sampson spent two days drinking out of a straw after his MMA fight in the US state of New Mexico and doesn't even remember most of the bout because he was concussed.
It was during filming for this first episode of Body Hack when he decided he needed a "safe word", Baltimore, which he would use if any of the challenges ever became too much.
"Throughout this series I thought 'Baltimore' but I never said it," he says.
"My director would pop up during really bad situations and say 'is this Baltimore?' I would bear down on my teeth and give him that face like I wanted to kill him."
That grit and determination helped Sampson to succeed in the business world. An advertising executive by trade, who was twice named Australia's CEO of the Year, Sampson created the successful Earth Hour initiative.
But the Canadian-born Sampson is best known by most Australians as one third of the ABC's sharp-witted Gruen team, who are on our screens every Wednesday night analysing the best, and worst, of advertising, marketing and spin.
"When a million people watched us in the first episode (of this season) with very little advertising it's like, 'okay people love this show'," he says. "When you know that it really does inspire you to want to make it better.
"I'd like to think people appreciate shows that are intellectual as well as entertaining. Sure I watch The Bachelor sometimes; I watch reality TV with my kids but I also force them to watch Brian Cox."
Three years ago he embarked on his first solo TV series Redesign My Brain, which won an AACTA Award and went on to become one of the most-watched Australian science documentaries of all time.
"I got an email two days ago from a young woman in Nigeria who said she uses it (Redesign My Brain) as part of her psychology class to teach kids," he says.
"I was absolutely thrilled to read that.
"A crusade would be going a bit far, but I'm definitely on a mission to get young people more interested in science."
Sampson is on his way to doing just that. Body Hack will be distributed internationally by Discovery Science and is expected to reach tens of millions of overseas viewers.
"I'm very fortunate to have a big platform to do what I love on such a big scale," he says.
"This show is about exploring extraordinary people to see what we can learn from their lives for ours."
He hopes the series, which has been described as Brian Cox meets Bear Grylls, will inspire viewers to make positive changes in their lives, no matter how small.
"I have this strong belief that we can all do much more than we think and science can help us get there. I don't care if you're completely out of shape. You can decode any challenge, any activity and you can be better at it.
"It's those small wins, those small achievements that build who you are."
Todd Sampson's Body Hack premieres on Channel 10 on Tuesday, October 4, at 9pm.
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