Earlier this week I went to hear a talk by a young neighbour who returned two weeks ago from a year-long, 15,000-mile cycle trip with a friend. Both recently qualified doctors, they had ridden from London to Singapore in aid of Médecins Sans Frontières; and they had ridden on bicycles they had made themselves – out of bamboo.

Bamboo is cheap, light, strong and, most importantly, highly shock-absorbent. Its use is championed by a London organisation, the Bamboo Bicycle Club, which runs workshops in how to construct one. Once sprayed up in shiny black, it’s hard to tell that the frame is made of anything other than carbon or titanium.

Tom Roberts and Nicky Moore built their steeds at the Bamboo Bicycle Club a few days before departing, last summer. Twelve months later, one of the bikes had made it all the way and one hadn’t quite (bamboo’s fatal flaw is that you can’t weld it). Happily, though, both riders had completed what turned out to be a more exhilarating journey than they could ever have imagined. A more gruelling one too: for example, riding for eight days on a diet of nothing but bread and butter at 4,000 metres, with night-time temperatures of minus 20, along the Pamir Highway in Tajikistan; and, by contrast, a 150-kilometres- a-day canter through northern India in 45 degrees while suffering from Delhi belly.

I came away from the talk greatly entertained, but also inspired and full of admiration for them, for their courage and endurance and good humour, for their belief in their charitable cause, and for their humility. ‘We were really just two blokes having a laugh,’ said Tom in answer to one question from the audience. Well, yes … but two blokes testing themselves to the physical and psychological limits, while staying friends with each other, and keeping in touch with the constantly changing peoples and landscapes around them.

The observations that struck me most were that the countries they had been warned would be the most difficult and hostile turned out to be the easiest and friendlest, while the most generous hospitality they received was invariably from the poorest people. I can imagine that there must have been something utterly disarming about two such genial young men on such an epic trip, turning up in some of the remote places they visited; but it also takes a great deal of trust and openness to throw oneself on the goodwill of unknown people in unknown lands.

They reminded me a lot of my own younger, more adventurous self, although the scale of their challenge was of an order of magnitude greater than anything I ever undertook. There’s no comparison between petrol power and pedal power, but I did follow part of their route my first summer at university, driving from London to Tehran with three friends in a VW bus. The thought of attempting that on a bicycle leaves me gasping, and it’s only about one third of the distance they travelled.

‘How has the journey changed you?’ asked one of the audience. ‘Ask our girlfriends,’ they joked. They couldn’t possibly know, just a fortnight after crossing the finishing line in Singapore. But it will have changed them, even though, as they pointed out, they were unlike many who undertake such trips in that they had taken off a finite amount of time, for a specific purpose, from careers they’ve just embarked on and are returning to.

I carry memories of my youthful journeys in my core and I know that they shaped me in ways I probably still don’t fully understand, more than 40 years later. The old cliché that travel broadens the mind is only part of it. Travel also opens the heart, it knocks off the sharp corners and smooths out the rough edges, and it nourishes the soul. If I was in need of a doctor and I had a choice between one who had gone straight from medical school into practice, and one who had first had to fix the chain on a bamboo bike in sub-zero winds on an empty plateau high in the Pamir Mountains, I know which one I’d choose.

You can find Tom and Nicky on Facebook at Cycling Without Borders, and you can donate to Médecins Sans Frontières via their Just Giving page at http://www.justgiving.com/cyclingwithoutborders