Tough Mudder is a half marathon with mud and obstacles and it's the biggest sporting challenge of my life. I have accepted the challenge because I want to support Nia tackling gender-based violence. 

Every hour in London, a sex attack is reported. That means 6,718 sexual offences and 3,267 rapes in one year, with many more unreported. Domestic violence is even more common; 46, 900 offences were recorded by the police in the same year. That's 5 per hour, or 128 per day.

Whether or not women want to go to the police, they can go to nia. A service local to north east London, nia is constantly developing new services to support those experiencing gender based violence. In addition to practical support, they help women put the abuse in context – placing their personal experiences in a wider framework of gender discrimination – which can stop them blaming themselves, and increases their commitment to changing their lives. They are vocal about how class and race relate to disadvantage, and they make a point of working with the women other organisations have refused - they run the only refuge dedicated to women who have problems with drugs and alcohol, and never deny access to those seeking a route out of prostitution as well as other forms of gender violence. 

They are simply brilliant. Let's get behind them!