A t 14, I decided to learn a martial art. I told my parents it was to defend myself on the mean streets of Congleton – a market town in Cheshire largely devoid of danger – when, in truth, it was because I wanted to be like Buffy the Vampire Slayer.

I joined a kickboxing club, and what could have been a passing phase became a thrice-weekly commitment spanning four years. I was a model student, picking up a different coloured belt every few months to mark my progression through the grades. I grew strong and flexible, swapping puppy fat for muscle. I routinely fought men without fear and found a confidence in my body I have never experienced before or since.

‘I was in the best shape of my life’ … Lauren in 2004. Photograph: Mark Potts

By the time I came to do my black belt grading in 2004, I was 19 and in the best shape of my life.…