Will Young - Young's Mankini Marathon Vow

The Leave Right Now hitmaker is in training for the 26.4 mile (42.2 kilometre) run through the U.K. capital in April (11).

He's participating in the race for Catch22, a British charity which helps disadvantaged youngsters - and he's seeking sponsors.

In a post on his Just Giving page, Young writes, "I am very excited/nervous about running the marathon for Catch22. With each painful mile I stumble along in my training I think of the potential money and profile I am raising for a charity that is very close to my heart."

And Young has promised to don a saucy one-piece male swimsuit, made famous by Sacha Baron Cohen in 2006 film Borat, for the 2012 race if he reaches his fundraising target this year (11).

He adds, "If I make £40,000 this year, I will do it in a mankini next year!"