Crossing the finishing line of his first double marathon, John Reynolds could not believe how far he had come.

Just five years ago the 46-year-old was bedridden with illness and unable to walk.

Perhaps more remarkable than completing the 53-mile race is the journey he took to get there, and the power of the mind to overcome anything.

It all started in 2003 when Mr Reynolds was receiving treatment at RUH for a thyroid condition. Lying in a hospital bed feeling sorry for himself, Mr Reynolds caught sight of the children's ward with where row upon row of youngsters were courageously battling through despite undergoing the same intensive radiotherapy that he was.

Mr Reynolds, of Radstock, was so moved by their bravery that he decided to, in his words, "buck his ideas up" and concentrate on getting better. And those children and their remarkable strength stayed with Mr Reynolds. So when, two years later, he was struck down with a mystery illness which left him unable to walk, Mr Reynolds knew he could not give up.

Rather than rely on doctors and drugs, Mr Reynolds decided he would recover with sheer determination and dedication.

It took him four hours but Mr Reynolds, who has two sons who live in Chippenham, Wiltshire, managed to walk to the end of his garden. He immediately told his cousins Stephen and Phil Ashford, who were delighted.

Mr Reynolds said: "After that they helped me walk a little further every day until I could complete a mile. Then I got to thinking about how I could help those children in the hospital so decided to run in the Midsomer Norton half marathon to raise money for charity.

"That was my target. I did it in two hours and 20 minutes. My cousins were there at the finishing line with a bottle of champagne. It was an amazing feeling. Stephen said it would be good if I could do a marathon next."

Tragically, Stephen suffered a heart attack aged 45 and died. Mr Reynolds was devastated but decided to run a marathon in his cousin's memory. So on what would have been Stephen's 46th birthday, Mr Reynolds completed the Snowdonia marathon – dubbed one of the hardest in Europe – raising more money for Children's Hospice South West.

Sadly, his other cousin Phil was then struck down with cancer. It affected his ability to walk and Mr Reynolds was determined to help his cousin and they started training together for the half marathon.

Mr Reynolds said: "I told Phil if he made it through the half marathon then I would run a double marathon. I know better than any, the importance of motivation and having a goal.

"Then, before he even had a chance to run the half marathon, Phil passed away too. I was distraught but knew I had to run the double marathon for Phil."

So, after months of training, Mr Reynolds this month completed a double marathon in Kent in ten hours and eight minutes.

He was also named Children's Hospice South West's "Champion for Children." after raising thousands of pounds for the charity.

A charity spokesman said: "John's achievement is fantastic and is a real testament to his personal drive and commitment. It is a real pleasure to support such a dedicated person and we're all looking forward to John's next challenge."

And Mr Reynolds, who has completed three marathons and 11 half marathons to date, said: "I miss my cousins so much and couldn't have done any of it without them but know I need to keep on going. Now it's the thought of the children I'm helping which inspire me."

If you wish to sponsor Mr Reynolds visit www.justgiving. com/johnreynolds-chsw.