IT’S almost four years since TV presenter Ben Fogle and Olympic champion James Cracknell embarked on a gruelling adventure that saw them row across the Atlantic in 49 days.

Along the way, the pair faced waves “bigger than houses”, a blazing sun that forced them to row without clothes, and wince-inducing blisters on their backsides.

“The Atlantic was hideous. I’m very proud we did it, but I don’t look back with very fond memories,” says 35-year-old Ben.

“But it didn’t put me off. If anything, it fuelled that curiosity about how far we can push ourselves and the boundaries of our own physical endurance.”

After sharing such an experience it’s no wonder the two have remained close friends. As Ben puts it: “James and I are very different characters. James is obviously very competitive, very sporty, and I’m neither of those. But we learnt on the Atlantic how we could work together with those strengths and weaknesses.”

It was towards the end of 2007 that the duo decided it was time to hatch another extreme challenge: a race to the South Pole.

“What we liked about this challenge is that a race like this, against other teams, had never been done before,” says Ben.

“It was a proper adventure, we weren’t going to be led by anyone. We’d stand or fall by our own mistakes. If something went wrong it was our fault, so we knew we had to put a lot of planning and preparation into it.”

BOTH married – James to TV presenter Beverley Turner, with whom he has two children, Croyde, five, and Kiki, three months, and Ben to Marina, who’s expecting their first child later this year – the pair agree it takes understanding partners to put up with their adventurous exploits.

“You know there’s no way you can explain it without coming across as selfish because it is selfish,” says 37-year-old James. “You’re going away to do something that is self-indulgent.”

In the months leading up to the race, Ben’s family was put under immense emotional pressure when he was diagnosed with a flesh-eating disease.

“I was in hospital for the month leading up to the departure and it was a pretty bleak period because we’d been planning and training for months,” says Ben.

Amazingly, doctors gave him the allclear with only days to go, although since returning from Antarctica the disease has come back and Ben continues to receive treatment.

“I was just very unlucky and even more unlucky for it to come back,” says Ben. “I hate to admit it, but it’s probably partly my fault that I didn’t recover enough afterwards.”

Training for the expedition started a year in advance. The team also embarked on mini-expeditions, including experiencing temperatures of minus 40 degrees in industrial freezers, learning to crosscountry ski in Norway, as well as attending training camps in Switzerland and Hollywood.

“Our third team-mate for about six months was the actor, Johnny Lee Miller,’’ says Ben. “But, sadly, he dropped out because of work commitments and also his girlfriend was pregnant.”

As a result, a national search was opened and Dr Ed Coats, an ex-decathlete, was selected as Johnny’s replacement.

But, for all the planning and training, nothing could truly prepare the trio for walking hundreds of miles while pulling a 150lb sled in temperatures up to minus 50 degrees.

Shortly before reaching the halfway point, when doctors assess all the competitors’ health before they are allowed to continue, James suffered pneumonia and for a while it looked like they were going to pull him out of the race.

“If you have to be rescued, it’s hugely expensive,” says James. “They didn’t want to put other people’s safety at risk either by me going out there.

“It would obviously also have meant my training had been wasted, but as you have to finish with the same number of people you start with, it would have meant the other guys would have missed out as well and I would have felt terrible.”

Having captured the high and lows of their Antarctic experience on personal cameras, which will be shown as part of the series, viewers can expect lots of emotion.

“We did a lot of the same sort of filming that we did on the Atlantic,” says Ben.

“And yes, there were many, many tears again.”

■ On Thin Ice starts on BBC 2 tomorrow, 9pm.