Since moving to London three and half years ago, I’ve travelled by bike. I moved without a job and couldn’t afford public transport. I took four hours of cycling proficiency classes under the Tower Hamlets cycle scheme to get my confidence up and haven’t looked back. There’s such a freedom to riding a bike: you can travel quickly and easily, even though you might arrive places a little damp sometimes.

Worldwide, there’s been a huge surge in cycle culture and huge conflict also. Bikes have been banned, knocked down and cyclists have kicked back. In his new documentary Bikes vs Cars, Swedish director Fredrik Gertten visits a number of cities across the world to explore the issue more deeply. I caught up with Fredrik for a quick chat.

The world premiere of Bikes vs Cars was held at South by Southwest in March. How was it?

It was fun! We organised the first ever outdoors screening at SXSW. We had bikes that pedal powered the screens and a big slow ride for an hour all around Austin. It was amazing!

After that I went to Mexico where the film is touring and we had bike rides in almost every city. It’s a fun and interesting movement. It's not a group of young radicals, it's much more complex with people ranging from sports enthusiasts to university professors – anyone who’s become fed up with cars.

At the end of the film you show bike lanes beginning to be introduced in São Paolo. Tell me more about where they’re at now.

There’s been rapid change in many cities and São Paolo is one of them; when we began I didn't know it would happen, but it did. In the future, I think cool and modern cities will be more bike-friendly and the mayor of São Paolo has understood that. However, since then there's been a court injunction against the bike lanes, so it's been stopped for a while and they've had big protests. People who lose their parking spaces get really angry!

Bikes are a part of São Paolo's transformation, but often when big changes happen there are a lot of people who don't understand. Car dependent people think they are losing out but they're actually winning; there will be more space for them in the end if more people move over to bikes.

Where’s your favourite city in the world to cycle?

My favourite is my own city, Malmö in Sweden. Whenever I come back from a journey I always feel blessed. It’s also amazing to cycle in Rio de Janeiro along the beaches, but there is not a full grid of bicycle lanes, so suddenly you're swimming with the sharks and that's scary. It’s just fun to bike in foreign cities. You see much more, you move much faster. If you go to Barcelona and rent a bike you can really get to know the city. In London you can ride along the canals and find quiet little side streets.

What is it that you love so much about bikes?

Bikes are so flexible. If you cycle past a shop and see a beautiful shirt you can stop and park. If you're in a car you can't park so you have to keep going. A car isn't flexible. People out in the city on foot or on bikes are good for the economy and local business. They stop and shop and consume so much more. When I was in Mexico City, the coolest restaurants in the city have bike racks outside and they're always filled. If you attract bicycles you can maintain a good business.

What are you thoughts on London’s infrastructure?

There's been a drop of 9% of cars coming into the city. The next step in London is to switch delivery cars to cargo bikes. It's much more flexible. Here in Malmö you can move your whole flat with bicycles! The only way for cities like London to grow effectively is without the car or it'll become gridlocked and won't work. You also have to make it safer to bike. My daughter worked in London for a while and she was too scared to cycle in town. If she felt safe, she'd have been on a bike every day. It needs to be safe and accessible for everyone. It’s also about happiness and quality of life; it's no fun being stuck in a line of traffic waiting. Always late!

In which city have you noticed the best progression?

I was recently in Mexico City and you can see more and more people on bikes, but the best? Probably Paris. New York and London are good too, but Paris has made the most impressive change. The whole election campaign was about traffic and mobility. Traffic is a really core political issue that everyone in Paris is talking about. So not only are they already a great bicycle city, but they also have great ambition to be even better. There's still a long way to go and a lot of conflict, mainly to do with money. A genuinely safe infrastructure costs a lot more than just a narrow white line down the side of the road.

Bikes vs Cars is being screened nationwide as part of the U.K. Green Film Festival.