Sir Chris Hoy left in excruciating pain as he tries to save hair for sake of son

Chris Hoy has spoken in depth about his cancer diagnosis and how he's been dealing with the news that he has a terminal illness, as well as an update on his wife's health

Olympic hero Sir Chris Hoy, who is battling terminal cancer, has revealed he endured agonising pain to save his hair for the sake of his 10 year old son. The 48 year old, who first announced his diagnosis earlier this year, has been told by doctors that he has 'two to four years' to live.

An 11-time world champion, Hoy is one of Britain's most decorated Olympians, having won six gold medals and one silver across four different Games - Sydney, Athens, Beijing and London. Also a father to seven year old Chloe, the dad of two has been fighting cancer for over a year and has now spoken in-depth about his painful battle.

In an interview with the Times, Hoy shared that his son Callum asked him: "Are you going to die? " Hoy reassured his young boy that while no one lives forever, he hoped that, thanks to medicine, he'd be around 'for many, many years'. Concerned about his dad losing his hair, Callum continually asked Hoy about it.

READ MORE:Sir Chris Hoy announces he has just a few years to live after terminal cancer diagnosis

READ MORE: Terminally ill Sir Chris Hoy's wife diagnosed with incurable illness in shattering news

To reassure his son and keep his cancer treatment private, Hoy chose to wear a cold cap during treatment, enduring excruciating pain. "It's like your head being in a vice," the 48 year old described.

Despite the intense pain, which Hoy described as the worst he had ever experienced, his hair was saved. "And I've got a very high pain threshold," he added.

During a particularly intense four-hour chemotherapy session, Hoy experienced a 'violent' allergic reaction. "I was absolutely broken by the end of it," he confessed.

"I feel like, 'What a wimp'."

Hoy, who married his wife Sarra Kemp in 2010, three years before retiring, shared more devastating news. In his forthcoming memoir, 'All That Matters: My Toughest Race Yet', he reveals that about a month after his stage 4 cancer diagnosis, Sarra was diagnosed with a 'very active and aggressive' form of MS.

"It was such a huge blow, when you're already reeling," Hoy remarked. Writing and recording his memoir was an emotionally taxing process for him.

"[You're] reading the words out loud, you have to connect emotionally. You've got to actually read in a way that means something," he said. "But the risk is getting too close to it – because you're suddenly thinking, these are the words that my kids will listen to when I'm gone. And that is, without doubt, the hardest thing I've ever done.'"

Since hanging up his cycling gear, Hoy has embarked on various new ventures, including motorsport, where he raced as a driver in the prestigious Le Mans race.

He has also served as a TV pundit during the Olympics and turned his hand to writing, publishing two children's fiction books.