Sir Chris Hoy has revealed the extraordinary sacrifice his wife Sarra made as he battled stage 4 prostate cancer — keeping her own devastating multiple sclerosis (MS) diagnosis a secret so she could focus on supporting him.

In his upcoming memoir All That Matters: My Toughest Race Yet, the six-time Olympic champion shared that Sarra first noticed unusual sensations in her face and tongue just a week after his diagnosis. An MRI scan confirmed early signs of MS, a degenerative disease affecting the brain and spinal cord.

But instead of burdening her husband with the news, Sarra chose silence. For more than a month she stood by his side through gruelling treatments, hiding her pain until she could no longer keep it in. Chris recalled the moment in December when Sarra, with tears streaming down her face, told him: “They think it might be multiple sclerosis.” He admitted he was “floored” by her courage, breaking down at the thought of what she had endured alone.

“She’s the strongest person I know,” Chris wrote. “She kept this to herself while supporting me through every appointment. Her strength and love left me in awe.”

Soon after, doctors confirmed that Sarra’s MS was “very active and aggressive,” demanding urgent treatment. Yet her priority remained Chris’s recovery.

The couple, who married in 2010 after meeting four years earlier, share two children. Chris described Sarra as “the centre of my life” and said from the moment they met, he knew she was everything he had ever wanted.

Following Chris’s cancer diagnosis becoming public, Sarra received a wave of love and support. In a touching post, she thanked well-wishers and called her husband her “real-life superhero.”