It's often said you have to be mad to attempt a marathon. Certainly the Guinness World Record attemptees in this year's Virgin London Marathon appear to have taken temporary leave of their senses.

Take 49-year-old George Bingham from West Yorkshire, who will set off from the start line in Greenwich on Sunday with a two-stone fibre glass model of the Angel of the North on his back.

Why? Well, because if he gets round London's streets with the 4.37 metre model intact he'll break the world record for the tallest costume worn while running a marathon by 10cm, and his name will enter the world famous annual of human superlatives.

"I ran the Great North Run with a smaller version of it in 2005," explains Bingham, who's hoping to raise more than £42,000 for Sue Ryder Care hospices. "A year ago I decided to run the London Marathon because, well, 13 miles isn't very far, let's face it," he joked.

Then Bingham found out about the record, and his model grew by 80 centimetres to be one 12th the size of the real Antony Gormley sculpture in Gateshead, complete with a wing span of 4.5m. Surprisingly, getting under the finish gantry in The Mall is not Bingham's main concern.

"If we get high winds I could have problems," says Bingham, who's not actually trained in his costume - "apart from running up and down the street a couple of times".

Then there's David Ross who will dress as Fred Flinstone and carry a blow-up stone-age club as he attempts to beat the record for the fastest marathon dressed as a cartoon character - a swift 3:36:07. The 42-year-old sales account manager has every chance for he's hardly a marathon novice. Indeed, he's run 175 marathons in 23 countries over the last 11 years, including seven in London.

"2:54 is my best out of costume," he said. "In costume I'm hoping to get under three hours. I thought running as a cartoon character would be great fun but the main motivation is that I wanted to give my fiancée a run for her money. She's already got a record - as the youngest woman to have run 100 marathons."

Ross, who works in the City, is raising money for Guide Dogs for the Blind. Most of his marathons have been completed in regular running gear, although two years ago he did run in a kilt.

So perhaps he will give Andrew White a few tips. The 39-year-old is aiming to run under 4:30:00 as the fastest marathon runner dressed as a nurse - in pinny and tunic.

"It chafes a bit but I think it will be OK," said Nurse White, who's trying to raise £75,000 for CLIC Sargent, the London Marathon's 2010 official charity.

White, who owns a Sports Marketing Business and has four London Marathons behind him, has trained only once in his costume - around Hyde Park at 7.30am with his 10-year-old daughter cycling alongside saying, "Daddy, why do people keep looking at us?"

"I only entered when my wife persuaded me - she who works with the charity," he explained. "Then six weeks ago a form arrived saying ‘What size nurse's uniform do you want?' I do feel completely stitched up."

Tom Soloman knows just how he feels. Soloman is a professor of neurology at the Walton Centre in Liverpool and admits he's not an athlete, by any means. "I can run around the block and that's it," he said. "I got rather duped into this by a colleague who phoned me while I was on my way to Malawi.

"I started training straight away, even in the airport, then when I was back in Liverpool I ran up and down the wards and back to the lab. The put a film of me on You-Tube called ‘The running mad professor' and someone said, ‘You have to run in costume', so here I am."

Soloman is aiming to beat 4:30:00 as the fastest marathon as a doctor, and looking to raise £13,000 for the Encephalitis Society. "I don't think I've got a cat in hell's chance of doing it," he said. "My colleagues think I'm pretty crazy anyway, but with this they think I've gone completely mad."

Soloman won't be the first running neurologist, nor the most famous, even if he does break the record. Sir Roger Bannister set the bar high for his profession when he became the first person to break the four-minute mile in 1954 before becoming a renowned neurologist himself.

Bannister's famous feat is perhaps the most well-known world record of all, and made him something of a hero for runners around the world for ever since.

And talking of superheroes, Jill Christie could be the quickest of all GWR attemptees as she aims to cross the line in around 3:10:00 dressed as Superwoman.

"I need to beat 3:13:33," explained the 27-year-old policewoman from Brentford. "I've done 3:21, but that was quite a few years ago."

She's also completed six long runs in preparation for Sunday, including one of 24 miles. "It was meant to be 20, but I got a bit lost," she says.

With her short skirt and cropped top, Christie will be relatively unencumbered by her costume, not so David Kidd, who's dressing as the children's book character Where's Wally, complete with his grandmother's old walking stick as the cane.

"She died at Christmas so this is a nice way of remembering her," said the 42-year-old from West Oxford.

Kidd is not the runner aiming to enter the record books as a children's character. Jonathan Zeffert will run in a baggy purple all-in-one furry outfit, otherwise known as Tinky Winky, the Tellytubby. The 32-year-old sales director needs to beat 4:30:00 to become the fastest television character.

"Last year I ran as a giant crab," he said. "But this is a good example of what happens if you let your children decide what you should wear. It was a close battle between this and Spiderman, and I'm beginning to wish I'd chosen Spiderman.

"I've been running lots and lots, and I'm hoping to get under four hours, but I think it's going to be a hot day."

Which is just what Michael Szymanksi fears. As a fireman, the 36-year-old from Southampton, is more than used to heat. But then he's not normally running in his work gear - a 40-pound uniform, including boots, helmet and oxygen canister.

"It is a little bit heavy," says the veteran of 10 marathons, including the famous 10-day Marathon de Sable ultra race across the Sahara desert. "I've done a fair bit of training in the boots and I've lost a bit of skin but it'll be worth it at the end of the day."

Szymanski needs to break 5:33:10 for the record. "This kit doesn't let any heat out so I am bit worried about Sunday because it looks like it's going to be hot. At least you get used to the heat a bit in our job."

And when he's finished? "I'll just give it a wash and take it back to work," he says. Mad? Not necessarily, but it helps.