Triathlete Matt Bagwell revels in his reputation as an iron man.

His latest stunt, however, seems a little ridiculous.

The 34-year-old website designer plans to spend four-and-a-half hours pressing clothes while running the London Marathon.

He will carry a 12lb ironing board on his back for the 26-mile race on April 18, stopping every five miles to press creases into items thrown to him from the crowd.

This feat of "extreme ironing", possibly the most bizarre sport on Earth, has never been attempted and could get Mr Bagwell into the record books.

He said: "I'm very happy to iron people's clothes on the way round but I'm talking about single garments."

Mr Bagwell, who lives in Eastern Place, Brighton, with wife Daisy, 35, and daughter Grace, three, has been running up to 15 miles four or five times a week with the board strapped to a rucksack frame.

He said: "I've got a German boss and he can't understand why anyone would want to run a marathon with an ironing board.

"My wife stopped questioning my mental state some time ago."

Extreme Ironing was invented in 1997. Devotees like nothing more than removing creases from their clothes halfway up cliffs, on top of mountains or in busy city streets.

Its creator Phil Shaw, from Leicester, says it "combines the thrill of an extreme sport with the satisfaction of a well-pressed shirt".

Quite how the irons are powered remains one of the sport's enduring mysteries.

Mr Bagwell said: "Depending on who you ask there are allegedly steam-powered irons and battery-powered irons but it's all a bit dubious to be honest."

He was introduced to extreme ironing by his brother-in-law Luke Cresswell, the man behind the Stomp theatre phenomenon.

He said: "He gave me a book on extreme ironing so it's all his fault."

Mr Bagwell says he has been brought up to iron clothes properly and is better at it than his wife, who is due to give birth again around the time of the marathon.

He is competing for Sparks, a children's medical research charity, and has raised £1,500.

Simply completing the course may not be enough. Mr Bagwell will be competing against an extreme ironer from the north of England who he describes as "much younger and fitter".

He said: "I don't know if we are going to be judged on time or the quality of our ironing. It's a race between two idiots."