A celebrity personal trainer known as Mr Fitness will tackle the Royal Parks Half Marathon two years after he suffered a stroke.
Greenwich man Jon Trevor will take on the 13.1 mile route, which starts and finishes at Hyde Park, in aid of the Stroke Association.
He will be pounding the pavements on October 11 alongside singer Lee Mead, Eastenders stars Jake Wood and John Altman, actor George Rainsford and former Calendar Girls actress Diana Marchment.
It was only when he was rushed to hospital after suffering arm pain and a droopiness to the left side of his face that the 55-year-old realised the diagnosis.
And the fitness fan said he felt he couldn’t disclose his condition to family, even going as far as to say he was “embarrassed”.
He said: “I thought strokes only happened to older people, or those with bad health – not me, a personal trainer.
“I lived and preached fitness and healthy living every day.
“I now know why they call it the silent killer.
“I remember feeling a mix of frustration and fear; I was most afraid that people who didn’t know me wouldn’t understand.
“I felt as though I’d be judged for having a stroke when I led such a healthy and active lifestyle.
“But I soon came to realise that strokes can happen to anyone, at any age.”
Doctors spotted Jon’s rocketing blood pressure when he was admitted to hospital in August 2013.
The symptom is the single biggest risk factor for a stroke and contributes to more than half of incidents in England, Wales and Northern Ireland.
But it doesn’t show any signs - which means many may not realise their health is in jeopardy.
Jon added: “By telling more people about my stroke I feel I’m able to not only educate, but to raise awareness to others about this devastating condition.”