A former couch potato is to run the London marathon on Sunday after just 100 days training.

Andrea Britt, 31, will be pounding the streets with tens of thousands of other runners in the hope of raising £1,750 for charity Outward Bound Trust after a gruelling training schedule.

In January Mrs Britt had never run more than three miles, but made the decision to take on the challenge after learning the charity still had a spot on its team.

She has now taken on a military style training regime, with her former Royal Marine husband as her trainer, and is hoping to complete the 26 mile course in under five-and-a-half hours.

She said: "I was really lazy. I can't believe how far I have come, I just hope it all goes well on Sunday."

To sponsor her visit justgiving.com/andreabritt