THREE years ago, Paul Sanderson was so unfit he could barely walk without breaking into a sweat. But after a three year weight loss mission, he is about to take part in the marathon, and said he feels fantastic.

He said: “I have sorted my life out, and I don’t know if I would be here otherwise. I feel fantastic, full of energy. It’s nice knowing I can do it, and I can run anywhere if I wanted to.”

In the last three years, Paul, 52, has lost ten stone – nearly half his body weight – after cruel comments from strangers became too much to bear.

He cut takeaways and “all the rubbish” out of his diet, and started walking around York racecourse. In only three years, he has slashed his weight from 21 stone to just 11, and tomorrow he will run his first marathon.

Paul said: “It wasn’t hard. I just must have been eating the wrong stuff before. I started walking round the racecourse and I’d walk further and go round more times each day.

“Then I started to jog a bit, and now I could run round there five times if I wanted to.”

Before he started losing weight, Paul had to endure constant comments from strangers about his size.

“I went into a takeaway once and a young girl said ‘you shouldn’t be in here, you’re fat’.

“I must have looked really bad, and I was on blood pressure tablets, falling asleep all the time and I had high cholesterol.”

His weight and poor health meant he could not dream of enjoying exercise.

“I used to sweat like mad, even when I was just walking. I didn’t have to go very far for sweat to start pouring off me, and my face would go bright red.”

Paul has done all his dieting and exercise alone, with just the help of runner Darren Bilton, who he met on a train on the way to a 10k race. Darren has helped him with training tips, and has set him a target of running each mile in nine minutes seven seconds to record a marathon time of around four hours.

Paul said: “I am nervous, and starting to wonder if I can do it. I will finish it, but it will be hard.”