My week: Sophie Anderton

The model, making her debut in the London Marathon on Sunday to raise money for charity

Run 13 miles around Hyde Park. It takes me just under three hours. This is the furthest I've gone. I've got metal in my right leg from when I was hit by a car aged 11, so I'm kind of taking it easy. It was recommended that I just do half the marathon but if it gets too much I'll hobble round. I don't want to do any damage. I've already lost my running partner, Tamara, to injury.

Monday

Work with my trainer for two hours. Use stabilisers and the fit ball followed by some cardiovascular work. I normally exercise for two hours five times a week anyway. I love my training but I don't find running easy. I can handle 13 miles but I'm not sure about the rest. I'm pretty terrified about running 26 miles. I'll be crawling or hobbling over the finish line. I'm certainly not planning on setting any records. I just want to get my medal and raise money for the National Autistic Society.

Tuesday

My last training day. Work on my abs, do lots of squats and lunges, then spend half an hour on the rowing machine and the bike. This afternoon I have dress fittings for a campaign I'm shooting in July. Later I indulge in a bit of retail therapy. On Sunday I'm going to be wearing the most unattractive pair of black shorts but they'll be brightened up with a Stella McCartney top emblazoned with my name. I've been breaking my new trainers in all week.

Wednesday

Rest up today. I'm kind of freaked out about the carbo-loaded diet I'm on. It's difficult. I've got to drink precision carbohydrates, protein drinks and lots of water. I'm obsessed with water and making sure my body is hydrated. I'm also taking isotonic drinks to put electrolytes back into my body. I feel like a walking encyclopaedia with all this new information. I've got to consume 2,000 calories a day which is horrific for a model but I'll be burning it all off on Sunday.

Thursday

I pick my parents up from the airport this afternoon. I wonder how the other celebs who are running for the first time are preparing. I admire Nell McAndrew who runs every year. She's amazing.

Friday

A press conference all morning with my charity. Then I'm off to see clients for modelling jobs. All my family are coming into town to support me this weekend. I'm feeling incredibly nervous. After the race, I plan to collapse with a Diet Coke and a big bar of Dairy Milk chocolate.

Interview by Lesley Wright