John McAvoy has spent 10 years of his life behind bars, at one time deemed one of Britain's most notorious criminals.
McAvoy's prison time stretched over two periods for separate armed robbery offenses.
For the second, he found himself in a high security unit with the radical Islamic preacher Abu Hamza among others.
But the death of a friend in a getaway car in a robbery made him transform his life through sport.
It began with punishing sessions on the indoor rowing machine at his prison aided by one of his prison officers.
He realized he had both an aptitude for suffering and also a lung capacity that helped him set record after record on the rowing machine.
It was then he decided instead to turn his attention away from crime and into training for the ardors of an Ironman.
As an amateur, he found himself surprisingly adept at the punishing discipline and is now taking on the world's best with a sponsor on board.
It is a discipline not without its pain but, having spent 10 years behind bars, McAvoy insists such suffering is easier to bear.
The 33-year-old is of the opinion he would now be dead had he not performed a dramatic U-turn.
His sights are set on beating the best in Europe next May but his criminal past precludes him from traveling to Hawaii for the World Championships.
It is both a life and sporting U-turn. Before he started training for Ironman, he could not swim and had not ridden a bike since he was 12.