Seeing you in action is like watching Spider-Man. How did it come about? It started when I was about 14, growing up in the Parisian suburb of Lisses, just playing around with my friend David Belle. We used to jump off small walls and other obstacles about the height of a chair, and then progressed to jumping from heights of three or four metres (10-13ft).

A legal high? You definitely get an adrenalin buzz and a sense of wellbeing — it’s simply like no other feeling.

How fit does a free-runner need to be? Most of my fitness comes from doing it. I practise for an average of four hours a day and I also go running and do abdominal crunches. When I was younger I used to do gymnastics and athletics, both of which are good for general flexiblity, strength and agility. The fitness and strength come with practice over time, though.

So it’s nothing to with your genes? No. Anybody with two legs and two arms can practise free-running. I’ve seen fat people and people over 50 years old doing it with no problems. Free-running is not all about big jumps. People always talk about those, but the small things — jumping up stairs or balancing on walls — are just as important.

Some of your jumps are spectacular.What’s the most death-defying leap you’ve ever made? The highest was from the top of HMS Belfast in London last summer. A security guard came up beforehand and was about to tell me how high it was, but I told him I didn’t want to know.

We don’t measure our jumps: it’s all about the feeling. And your favourite place to practise? I love the South Bank in London, especially the Shell building, because there are lots of trees and it is easy to get a grip on the walls.

Do you have to psyche yourself up beforehand? I work to a tailored programme that I call “physical meditation”. I focus on a point and blank out any distractions. When you do free-running, there are often noises and movements that can distract you into making mistakes.

Ever wimped out of a jump? Yes, many times, because it didn’t feel right. It’s not about the height — I might not jump because it’s wet or there are other unsafe weather conditions. It’s a question of analysing each jump and reflecting on it afterwards.

Have you always had an appetite for danger? I hate danger! It’s not about danger, it’s about knowing your capabilities. Our goal is not to seek out danger, but to take what we can from each performance and put this into action to make the jump perfect.

Ever had any serious injuries? Not through free-running. I broke my arm once while doing military service.

Are you hot on looking cool? I take an enormous amount of care of my body. The way I look at it is that our bodies are “our engines”. Therefore, I massage my muscles before and after I do free-running: that’s very important. I also think that it’s important to feel good physically, rather than look good.

What’s your poison? I don’t drink except at parties, and when I do it’s very little. And I don’t smoke either. But I do have vices like everyone else, namely McDonald’s.

So you count the calories? I eat everything, even pizza, but nothing to excess. I don’t have a specific diet, but I do eat a lot of pasta or other carbohydrates before doing free-running as it gives me the most energy.

Do you pop any pills? I take vitamin C and magnesium to help combat fatigue.

So what’s on the menu when you want to relax? I actually relax when I am doing free-running, but I find that music helps too. It can range from film scores to other genres, but it’s usually something which is relaxing or reminds me of something positive.

You’re 30 years old. How much longer will you be able to continue? Hopefully all my life, but I don’t know if I’ll always be able to perform at the same level of expertise.

Ultimate ambition? That my discipline is recognised by everybody in the world, and to live my life with my passion — free-running. I want to be able to have the means to share the philosophy of my discipline with everyone.

Sebastien Foucan features in Jump London, available to buy now on DVD, £19.99

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