Cardiac nurse Peter Sariwee lost six-and-a-half stone after noticing a similarity between himself and his patients.
Peter, 42, a nurse from Lancaster, lost the staggering amount of weight in just four months by simply taking up running and changing his diet.
And he now plans to complete a 69-mile ultra-marathon.
Peter knew it was time to start losing weight when he began noticing that many of his patients suffering from heart conditions and heart attacks were a similar size to him and leading the same lifestyle.
He said; “Seeing patients who were leading the same lifestyle as me having heart attacks was a real wake up call.
“I was a couch potato and spent my weekends binge drinking which wasn’t setting a good example and I knew I needed to change something.”
Although barely able to run for 10 metres, Peter saw an Iron Man event advertised in a magazine and decided to enter to give himself an incentive to lose weight.
Since then he has gone on to run more than 30 marathons and is now looking to challenge himself even further with Rat Race’s 69-mile ultra-marathon The Wall!
Peter added: “I am really looking forward to this event – it will be my longest run yet and I aim to complete it in just one day.
“Taking up running has been instrumental to my weight loss and I have found that by setting myself a target and a challenge to complete, such as a marathon, has helped me stay motivated and on track.”
The Wall is a cross-country ultra marathon journey organised by adventure sports company Rat Race.
It follows 69 miles of Hadrian’s Wall country between Carlisle Castle and Newcastle Gateshead Quayside over a mixed-terrain route that incorporates both on and off-road sections.