My biological mother gave me away at three months old. My adoptive dad was a good man, but a disciplinarian – I was beaten and never cuddled by him. You can either be resentful or turn it into a positive. Parenting is very important to me. I always send my children messages to say “I love you” and hug them every moment I can.

Being homeless and a single parent to my first daughter at 21 was difficult. I had a job, but it didn’t pay enough. When we moved into a council flat there were rats running around and one bed with bare springs. We made do. It’s part of the foundation stone of who I am.

Discovering fitness in 1983 was a lightbulb moment. I went from teaching in a church hall, to touring the country talking about exercise, to training Gloria Hunniford and Eamonn Holmes. It was like a sequence of dominoes toppling.

GMTV once told me that advertisers wanted a white woman doing fitness, not a black man. Eventually they asked me to come in for a rehearsal – and that was it. I’ve always risen above ignorance.

Wearing a brightly coloured unitard was my idea. I created an image that stayed in people’s brains – a white shirt wouldn’t have resonated. I added a co-ordinated bumbag so I had somewhere to hide my mic.

Cindy Crawford, Elle Macpherson, Meat Loaf, Cliff Richard – every guest on GMTV wanted to work out with me. Luther Vandross asked to be in the same dressing room and we had a lot of fun.

Today’s so-called fitness gurus need to stop and listen. Loads of 15-minute celebrities spin you a yarn and say “This is how I got fit” and when you check it, no they haven’t. When I talk about wellness, I’ve either lived it or met people who have.

Every day I do 67 press-ups – one for each year of my life. I have no intention of getting “old”. I look in the mirror and feel proud of what I see. My glass isn’t just half-full, it’s 100% full: half liquid and half air. I choose not to see the negative.

I’ve been with my wife for nearly 30 years – she’s my best mate. We’ve never had a cross word because I avoid what upsets her. We give each other space for “me time” – even love needs a holiday.

In 2010 we were tied up and robbed by guys with weapons in our home in Jamaica. It made me understand the only thing in life we’re sure of is right now. Enjoy every moment.

Do I miss breakfast television? Yes. I’d love to do a wellbeing programme now. But no matter where I am – music festivals, schools, cruise ships – crowds follow. I’m the Pied Piper of health!

The Warm Up by Derrick Evans (Mr Motivator) is out now (Filament, £14.99)