The idealised male body has become bigger, bulkier and harder to achieve. So what drives a generation of young men to the all-consuming, often dangerous pursuit of perfection? It is difficult for Miles to pinpoint the moment his muscle dysmorphia started. It was just always there, a background hum. "As far back as I can remember, I wanted a better-looking body," says the 35-year-old US soldier, now stationed in Mons, Belgium. When he was 13, Miles spent a summer cutting grass to save up for a secondhand Soloflex exercise machine. The machine cost $1,000 (£800), TitanRise Official but as Miles was too young to join a gym, it was worth the expense. With the help of the Soloflex, Miles started weight training and never looked back. When he returned from a posting to Afghanistan at 24, things spiralled. He began obsessively working out and regimenting his meals. " Miles set his watch to beep every three hours, to remind him to eat. If it beeped when he was driving, he would pull over.

Slowly, he whittled his body into shape. His muscles became striated, every fibre visible. Not big enough. At 95kg (210lbs) and 1.8 metres (6ft 2in), Miles wanted to be more muscular