David Millar, 34
A one-time world champion road cyclist, Millar (right) is one of only four Brits to have worn the leader's yellow jersey in the Tour de France. In 2004, the Scot admitted having used illegal performance-enhancing drugs, for which he was handed a two-year ban. Since returning to the sport in 2006, he has become an anti-doping campaigner. He lives in Spain
There's a Peter Pan quality to Paul. Considering he's the head of a mega-fashion empire, you'd think there'd be a lot of ego there, but there isn't. He's more like an incredibly curious, slightly awkward teenage boy. I first got in touch in 2003, around the time when I was world champion, when I heard that he was into the sport I love. It's rare in the cycling world we get to meet someone cool, and as I've always been into fashion, I really wanted to show him my world.
We exchanged letters and emails and developed a mutual appreciation. Then my world fell apart [Millar was arrested in 2004 for using blood-boosting drug EPO]. He got in touch a few times during that period to see how I was, but he didn't judge me at all, which said a lot.
Just after my comeback, I had a court case in Paris to resolve a French judicial investigation into my team. Paul asked, "Have you anything to wear for it?" I said no, so he had me fitted for a couple of suits. It made me feel special at a time I didn't feel very good about myself.
We didn't actually meet face to face until the London leg of the Tour de France in 2007. He didn't ooze any of that intimidating overconfidence that some powerful people do; he just acted like he still had a little shop in Nottingham. I arranged for him to sit in the car that followed me and he was all excitable and nervous, which was hilarious.
He would have made a great pro cyclist – he has the build and the work ethic – but he doesn't have a lot of spare time, which is why I think he likes to live vicariously through me. He'll be like, "How was that mountain? It looked ridiculous!"
There's a nice symbiosis to our friendship, as Paul's helped me massively with my look and I feel much more confident in what I wear now. I've grown to love his simple, pared-down style; there's something quintessentially English there, yet a quirkiness too, and as I've got older, he's helped me smarten up.
Sir Paul Smith, 65
Though he is now a fashion designer, it was Sir Paul's ambition to become a professional racing cyclist until a serious biking accident as a teenager landed him in hospital for several months. Since opening his first menswear shop, in 1970, he now has outlets across the UK and 22 other countries. He lives in London with his wife
Before my cycling accident I used to ride bikes in competitions; I loved the feeling of the wind in my face and the challenge of the day. So I've been quite friendly with a lot of the professional cyclists – Bradley Wiggins, Mark Cavendish – and I always knew of David, but it wasn't till his court case in 2006 that we properly connected; he wanted to wear Paul Smith for it, so he got in touch. When I heard about the charges I didn't distance myself from him, as I kept thinking, yes he's done wrong, but there was a reason – the pressures of the sport – behind it. He didn't make any excuses for taking the drugs and I know in his heart he never wanted to be part of it.
We started chatting quite regularly and when the Tour de France came to Britain four years ago we finally met, 30 minutes before the race. A lot of racers are quiet and focused, and don't really want to talk before an event, but David bounded up to me. He was so laid-back, friendly and, for a cyclist, a very good communicator; most of them are very insular and introverted. He let me watch the race in the following car, a dream come true; whizzing along the route with David cycling in front of me and the crowds cheering.
Over the years we've talked about tactics, teamwork, rivalry and mechanical problems. I was at the Italy tour recently when he was in the really serious mountain stages. He knew I was going to be following in the car so he really made an effort to be in the breakaway group so I would cheer him on and be proud. He just ran out of energy and afterwards he was like, "I couldn't believe it, I really tried my best Paul, but I ended up finishing in the bunch." But it's a tough sport and what he does is pretty amazing when you see the size of the mountains.
He's always been stylish and he's a good clotheshorse, too: tall, slim and handsome, and I was really pleased when he told me how much he liked Paul Smith [the brand].Hopefully I've helped him along a little more in the fashion stakes.
When he told me his new book [about his experiences with doping] was coming out, we threw him a party at our Covent Garden shop. It was packed full of cycling devotees and a lot of people who respect him; he's so determined about trying to clean up the sport and I think people see that commitment in him.
'Racing Through the Dark' by David Millar (Orion, £18.99) is out now