Freewheeling Stephen McKeown, who's clocked up thousands of miles for fun on his bike, is gearing up for a new marathon ride for charity despite having been plagued with what could only be described as a vicious cycle of heart problems.
Stephen, a 52-year-old supermarket worker from Dromore, is getting back on the saddle to prove that life goes on even after having endured a heart attack, triple bypass surgery, the insertion of a stent, lung problems and three long hospital stays.
And that's not the half of the horror story of his medical nightmares during which he was called a ticking time bomb who was at risk from a condition some people called the widow-maker.
Even so Stephen, whose exhausting exertions have helped countless good causes in the past, is preparing for a long-distance bike challenge in Britain that would test the endurance and fitness of many a healthier man.
He's setting his sights on pedalling 1,000 miles in June and July in England and Scotland on a journey which he's calling Cycle for Autism 2018.
Stephen's brother is autistic and his sibling wants to collect money for Autism NI, a charity that he says is 'close to his heart' - a pun he fully intends.
He also wants to raise awareness of autism which is a lifelong disability that affects the development of social and communication skills.
Figures show that one in 40 children in Northern Ireland have a diagnosis of autism.
From his own health perspective, Stephen thought he was in fine fettle until his heart condition surfaced out of the blue during his regular bike rides.
He says: "In many ways my love of cycling helped save my life because the irregularities mightn't have been detected otherwise.
"I had no absolutely no idea that there was anything wrong with me but on cycles during the winter of 2011/12 I became aware of a 'twinge' in my chest."
The pain kept recurring but it always went away as quickly as it came and at first Stephen wasn't unduly worried.
He says: "There were none of the classic warning symptoms like crushing chest pain, arm pain or shortness of breath, just a sore point in the same place in my chest covering an area of about one square inch.
"I was certain that it was just a chest muscle playing up and just cycled through it which, with the benefit of hindsight, wasn't one of my better moves.
"I later learned that somewhere along the way I'd actually had a heart attack of some description."
That finding was conveyed to Stephen after he wasn't able to ignore the twinges any longer and he was referred to a consultant cardiologist.
A treadmill test confirmed that all wasn't well. Stephen was diagnosed with angina and was told that he needed a lifesaving triple heart bypass.
But even after the surgery his problems were far from over. Two years later it was discovered that two of the three bypass grafts were completely blocked, requiring a stent to be inserted in the crucial left main stem - just weeks after he had been cycling 500 miles for charity.
Stephen was told that unknown to him he'd been a ticking time bomb who could have died at any moment from a heart complication that the medical teams nicknamed the widow-maker.
"I've been very lucky that everything was caught on by the doctors who were able to help me," he says.
After his procedures Stephen slowly regained his strength and though walking was tough, he was determined to get on his bike again and says: "I tried to do 1,000 miles around the UK for the British Heart Foundation and Diabetes UK in 2016 but I stopped 95 miles short of my target because I didn't think that my heart was up to completing the last bit.
"So the 2018 ride is unfinished business in a sense as I try to get that monkey off my back." And he's confident his health won't let him down. "I was able to do a 1,001 mile ride around Ireland last year without any hitches," says Stephen. "And on that 'Young Hearts tour' despite some terrible weather we raised £6,000 to buy a specially adapted trike for a workmate's daughter Grace McKee who was born with a complex heart condition in 2011."
This year Stephen is hoping to cover between 90 and 115 miles a day on a route that will take him from the Lake District and the Peak District, up to Edinburgh and down again to the ferry in Cairnryan.
It'll be a solo effort but Stephen won't be on his own. For a support team comprising his wife Pamela, his 12-year-old daughter Amy and cousin David Bruce will be shadowing him in a car, carrying vital cycling equipment and tents for overnight stays in campsites.
Stephen isn't taking a cavalier attitude to health concerns. Far from it. He'll be wearing a heart monitor which will feed readings to a display unit on his handlebars.
He insists: "I know the tell-tale signs to look out for. And I will respond immediately if I see anything that doesn't look right.
"The importance of all that was drummed into me at cardiac rehab sessions in hospital."
Stephen's stop-overs for his summer journey have also been carefully selected in locations which aren't far from hospitals. Just in case.
Stephen says he's had a series of check-ups in advance of the charity ride and his doctors have backed him with the proviso that he takes care.
Stephen says he has always tried to listen to the advice that he's received from his consultants and he has urged people to keep a close watch on any cardiac concerns that they might suspect are developing.
He says he's walking - or cycling - proof that the heart's a wonder.
He says: "I've had one heart attack, one open heart surgery, one collapsed lung, one partial left bundle branch block, fluid on my lungs, tachycardia, bradycardia, one angioplasty, three hospital stays, four treadmills, four echocardiograms, two angiograms, a cardiac CT Scan and more ECGs, blood thinning injections and blood tests than I care to remember in four years.
"And I reckon they are a reminder of what an eventful journey it has been in my case and how unpredictable living with coronary heart disease is."
But the ever-cheerful and resilient Stephen adds: "I'm still upright and breathing and it is what it is."
Stephen says he isn't undertaking any extraordinary training regimes in advance of his Cycle for Autism.
He explains: "I don't want to sicken myself completely of the bike by doing really long journeys But I still do the 24-mile round trip to my work three times a week. I also throw in the odd 15-mile round trip to see my parents.
"I still enjoy the feeling of getting out on my bike, especially in the open countryside. The Mournes, however, are more or less out of bounds because the terrain is just too taxing. I try to stick to the flatter roads."
Stephen, who's an Arsenal fan, has four bikes to choose from for his outings.
And for his charity runs he has had the backing of a former king of the roads. Morgan Fox is an ex-professional cyclist whose Planet X Ireland company supply carbon and titanium frame bikes to the Irish market.
"He let me have a bike and set me up with a lot of clothing and so on. His support and advice has been invaluable," says Stephen, who used to be a part-time photographer.
He's also a member of an exclusive band of survivors of open heart surgery who revel in the name of the Zipper Club, so-called because of the shape of the scar which is left after surgeons finish their work on their patients.
An online chat that Stephen did for the club was hailed as an inspiration for other members due to his positive attitude and sense of humour during what was "a real physical and emotional rollercoaster of a ride for the last few years".
And typical of the man, Stephen says he mightn't content himself with the 1,000 miles he plans to travel in Britain.
"Once the ferry docks in Northern Ireland I'll maybe just cycle home to Dromore," he laughs.