Previously an unfit beer-bellied office worker, Jeremy Scott did minimal training ahead of his almost completed 50,000 km ride from London to Auckland.
The 41-year-old architectural designer expects to complete his ride at Starship Hospital this month.
He set out from London two and a half years ago, captivated by the idea of returning to his native New Zealand over-land, and using the journey to raise money for the Heart Foundation.
The only training ahead of the trip consisted of a weekend riding in the Lakes District to check if his leg had recovered fully from recent surgery.
Scott had had read accounts of long-distance bike rides, he wanted to experience a life-changing adventure and felt it would be fitting to give something back to the cause of cardio treatment.
Aged four, his own life was transformed through a Greenlane Hospital operation, which repaired the seriously damaged heart he had been born with.
From being a lethargic little boy, barely able to play with others I received an entirely new lease of life. That affected me deeply and I always wanted to give something back to help children in a similar predicament, he says.
Pulling out his panniers on the eve of the trip and realising his entire world would have to fit inside them for more than two years was sobering.
My first days on the road were depressing, I'd never met anyone who'd done something like what I was attempting and I was beginning to doubt myself.
But after 10 weeks I'd ridden across Europe and all those doubts were gone.
I figured it would just be another 10 weeks to cross Turkey and another 10 weeks to almost reach China. Eventually I just started to concentrate not on my ultimate goal but on how far I could ride in a single day.
Scott says Holland, Belgium and Japan are extremely well set up for cyclists. But the most dangerous roads and drivers were in China and Indonesia.
There's so many vehicles on the road in these countries, so much pollution and the philosophy is 'the winner takes all'. In Jakarta it seemed like if I left a couple of centimetres between my front wheel and the next vehicle in front, somebody would squeeze their wheel into that gap to get in front of me. I basically learned to play by the game and not give any room to anyone.
However, despite the over-crowded roads, poor driving skills, frequent road crashes and woefully maintained vehicles, Scott no road rage on Asian roads.
"Our roads and driving standards are generally far better, yet when things go wrong drivers in the West are far less patient and seem to get 10 times as angry."
Generally he was received with kindness and generosity by those he met along the road.
He says the traditions of hospitality in Islamic countries, such as Turkey and Iran was particularly strong, at least for male travellers. But there were exceptions.
In Iran, an Inn where he stopped to ask for water, turned out to be a Mafia drug den where, after snorting their drugs, his gun and knife toting hosts attempted to make him a prisoner.
Scott managed to escape when several truck drivers stopped at the inn and ordered food. This distracted the men who he felt certain had been about to attack him. It provided witnesses to the dangerous way he was being treated and gave him an opportunity to excuse himself and leave.
Other "hairy moments" included being detained by Iranian military officials near an underground nuclear power plant; fighting off an Uzbek goat herder, who tried to grab gear from his saddle bags and fleeing Filipino gangsters in Cambodia. The last group had intended to drug him and get him involved in a high stakes card came.
The weather was varied, with Scott at times cycling through sand storms, typhoons and temperatures ranging from -20 to more than 50 C.
"But it really was the adventure of a lifetime and I have no regrets," says Scott.
"The big question now is what will be my next challenge."