He said: "I have lived with the fear of knowing that I could walk out of the doors having been told that I could never do sport again."
Black's career - in which he has won European and Commonwealth 400 metres titles and two Olympic silver medals - has been a rollercoaster ride of achievement and injury. But the heart problem which forced him to give up for a period as a schoolboy has been known only to his family and associates.
As recently as 1985, the year Black won the European Junior a heart specialist wrote to his father expressing reservations about the severe training he was undergoing. "I have to do this for reasons you will appreciate," the specialist wrote. Black's father, a GP until he retired in 1991, also suffers from a heart condition, although of a different type. Black also reveals how he suffered a serious heart scare in 1989, shortly after returning from a two-year absence with a foot injury. He was rushed to hospital when doctors suspected he had a potentially serious heart infection which might have required open heart surgery - and would have meant the end of his career.
After undergoing a week of tests, his problem was diagnosed as being a combination of pneumonia and psittacosis, a viral infection which can be caught from parrots.
Black, now 32 and due to retire after this season's European Champions, has missed only one heart check-up in the last 21 years. That was in 1996, as he was preparing to earn the first Olympic medal of his career. "Whatever I was told," he said, "I knew that that year of all years I would not have stopped running for anything."
How Long's the course? Roger Black: My autobiography is published on 25 JuneReuse content