But she did. On Sunday she speed-walked the 5km route around Alexandra Park, finishing in 80 minutes, and raising £220 for Cancer Research UK.

When the Hastings Observer spoke to Laura, 24, before she completed the race in April, she was 23st 4lbs, down from 38 stone following stomach stapling surgery last year, a strict 650 calories a day diet, and twice weekly gym visits.

Now she has reached an amazing 21st 8lbs.

Laura's 30st mother Doreen's died from obesity in 2005, so it was her aunts Ann Williams and Julie Martin, and the Falaise gym team who ran with her, who cheered her on at the finish line on Sunday.

Laura, of Stonehouse Drive, St Leonards, said: "1 hour 20 minutes was the best time I've done it in.

"It was an achievement. I've been training hard for that medal. I didn't expect to finish it. Even now I'm very taken aback.

"My aunties were there - crying, happy, proud.

"Before I set out for the race I was at home crying, thinking about my mum, and how she'd be proud of me, and would have loved to see me do it.

"I was watching the video of myself on Jeremy Kyle and thinking, blimey I've changed.

"It was a brilliant day. I'll be doing it next year in fancy dress."

Laura will be filmed for a Channel Four Cutting Edge documentary later this year, about her weight-loss publicity.

"Two years ago I was 37 stone and I couldn't even walk around my flat, never mind the park. It's a huge achievement," she said.