8 Things You Won't Know Unless You've Run The London Marathon

As thousands of runners prepare to take part in the London Marathon, we find out what it's really like to take part in the gruelling challenge.

1. People take the piss, literally. You'll need to be well hydrated from the off, but there's lots of hanging about before the race begins. Blokes tend to pee in plastic bottles; you'll need to time your pre-race toilet stop or be prepared to wee behind a tree.

2. You need to wrap up for the warm up. You'll be waiting around in a plastic bin bag or foil blanket before the start - everyone chucks them away once they get running, though.

3. You look uncool. My running partner and I had our names emblazoned across our races tees. Not tres chic, but when total strangers shout out for you, it's a real boost.

4. You won't live it down if your friends catch you walking. I told people where to wait on the race route so I could look out for them. I didn't want them to see me walking, so it was a great incentive not to give up.

5. Embarrassing moments are rife. No, I mean really embarrassing. Every year some runners will poo themselves, often because their stomachs aren't used to all the free sports drinks being handed out along the route.

6. Beware jogger's nipple. I smeared Vaseline absolutely everywhere - over my boobs, under my bra straps, between my thighs and even between my toes.

7. You need a plan. Have a goal time before you start, divide it into minutes per mile, and stick to it as closely as possible. It's easy to set off too fast or lose the will at mile 17, so keeping to a schedule really helps.

8. They take your photo at the finishing line. So if you get there, don't forget to smile!

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