Jonelle Roback was ready to run, the 45-year-old having prepared for months in her quest to prove that someone with Multiple sclerosis can complete a marathon.

But at the end of December, her hopes were shattered when a change of medication led to a relapse.

"My neurologist gave me the devastating news that I wasn't to push my body at all and to withdraw from the marathon," she recalled.

"It was a shame, because it was the one thing I always wanted to do."

That left her husband, Jonathan, to represent the family.

The couple, members of Mosaic Reform in Harrow, had originally planned to run together and Mr Roback was keen to fulfil his part of the bargain, despite never having run a significant distance.

He found a personal training programme, followed it to the letter, and came home in a respectable 4:45, raising at least £7,500 for the Multiple Sclerosis Society.

Mrs Roback said that she and their two teenage children were "very proud of him. He did what I couldn't do and it was amazing.

"He never wanted to do it and I'm not sure he enjoyed it."

But Mr Roback, a finance director at a teaching recruitment company, may have caught the running bug. "I think he's considering doing another one now," his wife confided.