"I've got Parkinsons, it hasn't got me" - that is the mantra of a 58-year-old fitness instructor gearing up to cycle 1,200 miles across Thailand and Burma to raise money for research into the disease.
Ex veteran and former butcher John St.John-Mosse, who was diagnosed with the neurological condition nine years ago, has already raised £52,000 for Parkinsons UK.
He has completed sponsored challenges such as climbing Mount Kilimanjaro and cycling in Vietnam, Cambodia, Laos and Thailand.
But the determined husband and father-of-one, of Tudor Drive in Morden, believes the 12-day solo ride in October will be his toughest journey yet.
He said: "I'm fit as a fiddle at the moment but it's getting worse and I might not be able to do it next year.
"This is the biggest physical and mental challenge of my life and I need to do this before my condition stops me."
Temperatures are likely to reach 38 to 40 degrees centigrade during the trip which will mostly cover mountainous terrain.
Mr St.John-Mosse, whose unusual surname was chosen by his Iranian father so it would sound less Jewish during the Second World War, said: "I would never have done it if I hadn't got Parkinsons.
"I would never have dreamt of going there.
"I will finish it. If it means cycling 24-7, I will do it. I know I'm going to push myself to my absolute max on this. I want to raise as much money for Parkinsons UK as I possibly can."
He added: "Having a positive attitude with Parkinsons really does help - and having fitness, good exercise, cycling.
"When I'm on the bike I can be a completely different person.
"I can be anybody who I want. Just because you've got Parkinsons, it doesn't mean to say you're life's finished."
Support Mr St.John-Mosse by donating at justgiving.com/gonecycling.
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