I'm confident of what I have to achieve in the buildup to London 2012.

A half marathon is a good way to have a bit of fun and race against those girls and learn a bit more about them.The world half marathon is a world championship at the end of the day and it's important. I've win it twice and it's a quality event.

I start planning then that's dangerous because then I have a target that I'm blinkered towards and I won't listen to the warning signs quite so much. I'd rather be in shape and then look around and say there's a race next week and jump into that than have it planned.

I have achieved a lot and I'm grateful for that - I'm just a bit greedy because I want to add the Olympics. It's once every four years - everyone wants it and very few people get it.

It's important that athletes can compete on a level playing field. And youngsters coming into the sport can know that if they are working hard and training hard, they'll see a true reflection of where they stand and what they can achieve worldwide and not be swayed by people who are cheating.

From my training I can get a good idea of what I'm capable of.

No one remembers who came fourth.