Craig Bulloch was doing everything right, exercising and eating well, yet he had a heart attack at the age of 34.
But Mr Bulloch's exercise is more than a jog around the block. He has completed half-ironman events and - having recovered from last February's health scare - he competed in last month's Auckland half-ironman and has entered next month's full-distance NZ Ironman at Taupo.
It was while training for last year's NZ Ironman that he had his heart attack.
"It was 10 days before the ironman. I went out for short runs to make sure everything was going okay. I felt some chest pain. I just thought it was a bit of exhaustion as it was pretty hot. I didn't think anything of it and just kept running. I got home and started speaking to the girlfriend. We decided I should go and see the doctor in the morning.
"Next morning I went to the doctor, had blood tests and they found I had had a heart attack. They ended up putting a stent in [a wire mesh to hold a heart artery open]. There was 75 per cent blockage of an artery.
"They said if I had been unfit and stayed the weight I was, the heart attack I was going to have was going to kill me. Being active, it was just a small heart attack."
Mr Bulloch, an Auckland aluminium joinery salesman, took up ironman training in 2010 to turn his life around.
He weighed 120kg and was on medication to treat depression. He said that setting goals and training had made a complete change to his mental wellbeing, and he was now down to 87kg.
The heart attack was a set-back - he had to cut down on exercise for six months - but he is now back on track.
The cause of his health scare remains unknown.
"They just said I must have been susceptible. They couldn't understand it."
He had no family history of heart disease, stopped smoking five years ago, his cholesterol levels and blood pressure were fine and there was no sign of heart problems attributable to exercise.
There is emerging but controversial evidence that long-term extreme exercise causes excessive heart wear and tear.
Mr Bulloch, who now takes a daily aspirin and statin medication, chose to speak publicly to help the Heart Foundation's annual fund-raising appeal. "I was the fittest and healthiest I have ever been and I still had a heart attack. Everyone should have regular heart checks."
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