By braking hard just before a bend, cyclists descend much faster from a mountain. Scientists from TU Delft discovered this with a special measuring bike in collaboration with the Giant-Alpecin cycling team. In addition, the scientists determined how best to ride a time trial. The Giant-Alpecin drivers take advantage of it during the Tour of Italy. And did you know that you cycle faster because of a Slush Puppie?
“A cyclist does not win the Tour de France or Giro d’Italia during a descent. But he can lose a big lap there,” says Arend Schwab of the bicycle dynamics lab at TU Delft. He is a bicycle expert and together with colleagues he built a measuring bike to find out how best to descend from a mountain.
Our time
Schwab is working together with the Giant-Alpecin cycling team, one of the teams that will start in the Tour of Italy next Friday. The eye-catcher of the team is the Dutch cyclist Tom Dumoulin. Last year he caused a sensation by wearing the leader’s jersey for six days in the Vuelta a España, in which he eventually finished sixth. This year he won the opening stage in Apeldoorn of the Tour of Italy.
Giant-Alpecin and Schwab are trying to better understand how best to descend. This subject has always fascinated Schwab. Because there were all kinds of stories about it. “There are many statements from professionals and cycling fans. You would descend faster by leaning into the corner a certain way, choosing a certain line or braking very late. But those are all assumptions, based largely on just looking at the cyclists. We wanted to measure what actually makes the difference. We have small sensors at our disposal that measure anything and everything. That is the beauty of our time and the development of microelectronics.”
Brake late and hard
Together with colleagues, Schwab built a measuring bike chock-full of sensors. The smart two-wheeler measures, among other things, the position on the road, speed, power, how hard a rider brakes and the steering treatment, i.e. how far someone leans in a certain direction. There is also a camera on the back, so that the researchers can check what happens during a ride.
Six Giant-Alpecin riders descended on the meet bike from the legendary La Plagne mountain, where Michael Boogerd won a stage in the Tour de France in 2002. What turned out? The riders who brake late and vigorously just before a corner descended the fastest. “That may seem obvious, but we have now actually established it with this research. It’s not based on stories or just looking, but on data we collected during the ride,” says Schwab.
The researcher does not rule out the possibility that other factors play a role. “Unfortunately, not all systems on the two-wheeler worked equally well. The GPS to locate the cyclists on the road was not accurate enough and the camera often fell off the bike. We were able to look at the lean angle, steering angle and braking behaviour. And so we saw a significant difference in the latter.”
Fear
Thanks to this test, Giant-Alpecin’s cyclists have an advantage over the competition. They know that they have to brake later and could already practice on it. But putting that insight into practice is not so easy, Schwab suspects. “The time you brake is of course related to fear. You can’t just take that fear away. A number of cyclists were also very interested in our results and were eager to get started.”
Schwab is going to do more tests again in collaboration with the cycling team. The researcher wants to find out how scared a rider is. “I don’t know exactly how we’re going to look at that. Maybe we’ll look at the size of the pupils. Tips are welcome. Measuring sweat and heart rate is difficult, because they all sweat and are already making an effort.”
Seconds game
In the near future, Schwab would like to build a bicycle that indicates when cyclists should brake. “Then you indicate with a green light that you don’t have to do anything. A red light then stands for braking. This way the cyclists know exactly when they have to do what. You actually make a remote-controlled bicycle. As long as that’s not against the rules, I don’t see why a cycling team can’t use it.”
Schwab also sees room for improvements in the time trial. Research in the TU Delft bicycle lab has already shown that it is important to look at the power that a cyclist delivers.
“The distribution of wealth is essential. A mathematical study of our lab has shown that,” says Schwab. “Of course there is a maximum to how much power a cyclist can deliver. To perform optimally, an athlete must divide this during a time trial. He or she must deliver more power during a climb and less during a descent. Then you take it easy and you recover.”
Thanks to this insight, Giant-Alpecin is already creating so-called power profiles for riders. They know exactly how much power they have to deliver during the ride. “The average speed is higher than if you don’t do this,” says Schwab. That sometimes saves seconds. In a time trial, which is often a game of seconds, that can make the difference between winning or losing.
