Sir Ranulph Fiennes is not someone who strikes you as giving much truck to weakness.
This is a man after all who chose to confront his vertigo by conquering both Everest and the Eiger.
Cut him and one suspects he bleeds grit, pluck and a curiosity that has taken him to the top and bottom of the world.
However, ‘Ran’ says that there are still times when his will is tested – by those till-side temptations when he stops to fill his car up.
“You can’t pay for your petrol without being surrounded by the best chocolate, just when you are tired,” he says. “It must be put a stop to.”
He is struggling to give up his favourite treat, finding it harder to say no to than the cigarettes he quit 30 years ago.
But he is trying “very hard to behave” and change his diet after he was diagnosed as being in the pre-stages of Type 2 diabetes.
He realised something was wrong at the most inopportune moment, pulling out of an attempt to co-lead the first team across the Antarctic during the polar winter after suffering frostbite - caused because he was repairing a ski binding without gloves in temperatures of –30.
“I couldn’t understand why my circulation which had been so good for so many years had suddenly become bad in one hand and not the other, which I now know.
“I suppose I was quite lucky – although I didn’t feel like it – discovering it when I did rather than letting it get deeply into my body before having a chance to mend my ways food wise.”
The expedition itself, dubbed The Coldest Journey, was ultimately called off a few months after it started when the teams entered a crevasse field so vast it was impossible to negotiate with the heavy equipment.
Even though Ran turned 70 this year, he is still itching to get back out there to complete what he describes as “the last big one” in terms of expeditions.
“We or the Norwegians have broken all the records except that one.
“You can invent new ones, all sorts of gimmicky things, but for genuine man against the elements, the winter crossing of Antarctica is the last.”
He will be recounting some of his adventures at Birmingham’s Town Hall next week in a talk called Living Dangerously.
Dubbed the “world’s greatest living explorer” by the Guinness Book of Records, he has plenty of material to draw from.
“We have broken a number of world records over the years against our rivals, including the Norwegians. I’ll probably concentrate more on the ones where we broke the record rather than the ones where we haven’t,” he says.
“The Norwegians have been the great rivals on the polar expeditions.
“On the desert expeditions there’s no sign of them. I assume they feel more at home in the cold. They are certainly a hardy lot when it comes to the ice.
“For the archeological (expeditions), looking for lost cities, that sort or things, the German archeologist groups are probably the foremost ones that you hope are not as clued up as you are in finding whatever it is you are looking for.”
There is very little terrain that Ran hasn’t covered in his pursuit to be the first to be somewhere remote or do something seemingly impossible in the most gruelling conditions.
A few of the accomplishments that have earned him his place in the record books include being the first to circumnavigate the world along its polar axis, leading the first hovercraft expedition up the Nile – the longest river in the world, completing the first unsupported crossing of the Antarctic Continent (with Dr Mike Stroud) which was the longest unsupported polar journey in history, and discovering the lost city of Ubar on the Yemeni border in 1992, after seven previous searches.
This last triumph he shared with his late wife, Ginny.
“She spoke extremely good Arabic and she was like a terrier, she was determined to find it.
“It took 26 years. If we’d had to say we have wasted all that time, all those different sponsors and we have never found it, it really would have been sad. So when we did find it through luck it was really great. We were on a high for quite a long time.
“After that we went back to cold things.”
Raised in South Africa for the first 12 years of his life, he says he prefers adventures in the desert to the frozen wastes.
“I only went back to cold because the media give it more interest and that is what the sponsors want and we can’t do anything without them,” he explains.
All his trips are sponsored. Money raised through the trip goes to charity – “Altogether my expeditions have raised $16.3 million” – while he scratches a living on the lecture circuit and from writing books.
He says he only turned to this unusual career because of academic failure at Eton.
“Until I was 24 I only wanted to do one thing which was to do what my dad did and be a commanding officer of a wonderful Scottish regiment, which he was killed commanding in the war (he died a few months before Ran was born).
“But you couldn’t go to Sandhurst without A levels.”
He did join the army and was eventually seconded to the SAS but was “thrown out for bad behaviour with explosives”.
He had been trying to blow up an unsightly dam built in a pretty English village by the crew filming Doctor Dolittle.
He offered to unset the fuses after being rumbled and got off with a fine, narrowly avoiding a prison sentence.
“If it had happened one year later, after the IRA had started using explosives on mainland Britain, it would have been treated not as a prank but as a crime.”
His profession has not been without physical cost, most famously some of his fingers to frostbite. But he has treated illness and injury as another challenge to be overcome.
He sawed off his own necrotic fingertips with a fretsaw.
And when he suffered a heart attack and had to undergo a double heart bypass, he picked himself up and ran seven marathons in seven days and in seven continents in aid of the British Heart Foundation.
Even fatherhood hasn’t slowed him. His second wife, Louise, gave birth to their daughter, Elizabeth, in 2006.
“I am still debating that one,” he says when I ask him if it had changed his attitude towards pitting himself against the elements in far flung corners of the earth.
“I do not really come up with a full answer to it. It certainly does have a big effect.
“My late wife and I were married for 38 years and if we had had children I am not sure if we would have been able to do the things we did.
“I hope I am not going to hang up my hat. I still feel that draw to go out there and do more.”
* Sir Ranulph Fiennes: Living Dangerously will be at Birmingham Town Hall on Wednesday, June 18. For tickets call 0121 345 0600 or look up www.thsh.co.uk
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