A 'grossly obese' Glasgow man was furious after being told by his GP he'd die if he didn't lose weight.
Derek Friel, 34, was shocked when his 'brutally honest' doctor said he was 'close to death' after his weight ballooned to 24.5st.
At first, Derek was left infuriated by the diagnosis and was in denial about what he needed to do.
The Castlemilk man said: "I had a pain in my foot and went to see about it.
"I was diagnosed with having gout and the doctor started telling me it was down to my weight gain.
"Basically she said I had to change my life or I was going to end up dead. It was definitely a shock.
"I was raging. I thought 'how dare she be so rude?'.
"She was so blunt ."
Now, just a year-and-a-half on, Derek has dramatically changed his lifestyle and has got his weight down to just 16.5 stone (106kg).
'The Fat PT', as Derek refers to himself as, has lost eight stone in 18 months.
He is a fully qualified personal trainer with dozens of clients all inspired by his story which he is set to share in his incredible journey in a new documentary.
Derek added: "A few weeks after my appointment I realised something needed to change.
"I began asking myself - ‘why is she saying that?’.
"She doesn’t know me or who I am. She has no reason to say that to me if it wasn't the truth.
"Looking back it was obviously the push I needed. I'd even like to thank her for being so brutally honest with me."
The self-funded documentary - due to be released next month - showcases Derek's progress across the 18 months after he made the decision to return to his former trainer, Tony.
Derek explained: "From my very first PT session with Tony, I’ve documented every session I’ve had with him. You see on video all my struggles. Now it’s looking back to that, watching the video again and talking about how I feel at that time.
"It’s to try and help people understand ‘life isn’t always rosy’, especially when you’re on a journey that’s going to change your life. I’ve shown people my struggles and I think people resonate with that a lot.
"There’s moments where I feel like giving up, then the following week it shows I’m so glad I kept pushing."
And, as shown within the documentary, a particular moment of pain - and subsequently inspiration - for Derek comes from a seemingly innocent trip to the Irn Bru Carnival six years ago.
He said: "I went to the Irn Bru Carnival six years ago. I was with my ex and her wee boy and I was too big to get on the ride. That was one of the low points of my life. Her boy is asking why we’re not going on it, we’re saying ‘it’s broke’ and he responds ‘but everybody else is on it’.
"It was down to me abusing myself and abusing body, that he’s getting into trouble for asking questions and me and my ex are arguing. So I talk a lot about relationships and how it affects relationships as well. There's more to it than just losing weight.
"And at the end of the documentary I go back to the carnival and go on the ride - when I go back, I’m still very nervous.
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"I look well, but I’m still that fat guy inside. I’m trying to get that out to people as well - you might see this as great but I still have struggles now. It helps by talking about them."
Derek is hoping to launch a Facebook community in the near future in a bid to make personal training more affordable for the average Glaswegian, a luxury often out of reach for many.
