René Keusen, deputy head of logistics for the Cantonal Court of Zurich, Switzerland

I've already had two slipped discs. And on top of that I have trouble with my knees: I have split kneecaps, which actually isn't that unusual. Lots of people round the world have them. But it has given me a lot of gyp. I used to work in an opera house, and that was physical work. That's why I was forced to give up that job to go back into education or retrain to return to my old job. Since then, I've managed a couple of months without pain. That is, I still get exercise. I strengthen my stomach and back muscles. At first I was quite sceptical about kybun shoes, as I didn't like the way they looked. But I told myself that if they might be of benefit, I should at least try them out. Now I never want to be without them again. The feeling I have when I walk and my general wellbeing are quite different.