Britain's six-time Olympic track cycling champion Chris Hoy has revealed he has "two to four years" to live after he was diagnosed with terminal prostate cancer which metastasized to his bones.

The announcement comes after the 48-year-old Scot said in February he was feeling "optimistic and positive" as he was undergoing treatment for an unspecified cancer diagnosed last year.

However, the sprinter, who worked as a pundit with the BBC at last summer's Paris Games, has now revealed he has known for more than a year that his cancer is incurable.

Despite his illness, Hoy says he remains positive and appreciating life.

"Hand on heart, I'm pretty positive most of the time and I have genuine happiness," Hoy told The Times.

"This is bigger than the Olympics. It's bigger than anything. This is about appreciating life and finding joy."

"As unnatural as it feels, this is nature. You know, we were all born and we all die, and this is just part of the process."

Hoy wrote a memoir about his life over the past year in which he describes how doctors discovered his cancer after initially finding a tumor in his shoulder.

The father of two also said he had an allergic reaction to his chemotherapy treatment, feeling "completely devastated at the end of it."

On top of his own treatment, Hoy was dealt another blow when his wife Sarra Kemp was diagnosed with multiple sclerosis in November.

"But you remind yourself, aren't I lucky that there is medicine I can take that will fend this off for as long as possible," an optimistic Hoy said.

"I'm not just saying these words. I've learnt to live in the moment, and I have days of genuine joy and happiness."

"It's absolutely not denial or self-delusion. It's about trying to recognize, what do we have control over?

"The fear and anxiety, it all comes from trying to predict the future. But the future is this abstract concept in our minds. None of us know what's going to happen. The one thing we know is we've got a finite time on the planet."

Hoy was at the vanguard of Britain's era of domination in track cycling, winning gold medals at the Athens, Beijing and London Olympics. He also claimed 11 world titles during a glittering career.

Until 2021 Hoy was the most successful British Olympian and the most successful Olympic cyclist of all time before being overtaken by fellow Briton Jason Kenny who claimed his seventh Olympic gold at the Tokyo Games.