Rugby fans heading through London's Waterloo station on their way to the England versus Wales game at Twickenham yesterday were the target of the first major advertising campaign by a male rape charity.

The charity's poster has already caused controversy after appearing in London underground stations last week to coincide with the Six Nations tournament. Featuring a rugby ball pierced by a nail and the message "Real men get raped and talking about it takes real strength", the adverts will also feature on electronic billboards in March when England play their final home match against Ireland.

Michael May of Survivors UK, a charity that runs a helpline and counselling service for adult gay or heterosexual men who have experienced rape, said the campaign was a response to new Metropolitan Police figures which reveal that on average, in London, a man is the victim of a sexual crime every hour.

The government estimates that 11% of male victims report being attacked. Therefore, May believes, the 945 assaults recorded by the Met in 2009-10 suggest a true figure closer to 8,500 in the capital.

"The alpha-male imagery of rugby is clearly suited to challenging the assumptions about male rape," May said. "A victim is just as likely to be a rugby player as a City banker or a gang member. And we hope that by challenging our innate assumptions about the identity of male victims, we can make it even fractionally easier for a male rape victim to ask for help.

"The posters are proving a bit controversial, but we need to get more men coming forward with their experiences and lose the taboos that hold them back from seeking help."

Professor Kim Etherington, a fellow of the British Association for Counselling and Psychotherapy, said men faced deep-rooted fears about reporting a sexual attack or admitting they had been raped: "Males are taught from a very early age that they should be 'strong' and 'in charge'. To be successfully masculine is to be sexually potent, competitive with other males in sexual matters and dominant with sexual interactions. Being raped challenges and negates all these preconceptions."

A review of male-victim sexual assaults led the Home Office to put aside a small pot of money to help victims. A report last year by Baroness Stern acknowledged that the vast majority of male victims of sexual violence do not report it because of the view that men "should be able to fight off an attacker".

The review recognised that men do not come forward for fear of being ridiculed or disbelieved, or for fear they may be seen as gay, or because they do not wish to be regarded as less of a man.

The Survivors UK Helpline is on 0845 122 1201 (7pm-9.30pm on Mondays and Tuesdays; 12pm-2.30pm on Thursdays)