The Paris Olympics wanted a fast track, and they got it. Here's how

The track at the Stade de France for the 2024 Paris Olympics had two requirements: it had to be purple and it had to be fast.

The colour was meant to be fitting for Paris and to create a unique stage for the athletes to perform on – it is a lighter shade than the typical red track, echoing the track at the 2016 Rio de Janeiro Olympics, which was the first to feature a navy blue rather than red.

Increasing speed is not as simple as a design choice — in fact, “fast track” has become one of athletics' most overused phrases — it's unlikely that a host city would request a slow track.

But Paris Was BREAKING NEWS: Seven Olympic records and three world records in track and field were set at the Olympics, excluding the world bests in the decathlon and field events (hammer throw, shot put), which do not use a runway or track.

The number of combined Olympic and world records has been on the rise in recent Olympics: five in London (2012), six in Rio, 10 in Tokyo (2020), and the same number in Paris. It's an oversimplification to say that athletes are getting bigger, faster, and stronger. People are getting smarter, and technology is improving.

In Paris, it wasn't just the records that were set, but also the way they were achieved: 13 runners beat the 10,000m Olympic record (27 minutes, 1 seconds) set by Kenenisa Bekele in 2008, with Joshua Cheptegei of Uganda winning in 26 minutes, 43 seconds.

In Tokyo, four men, including Jakob Ingebrigtsen, broke the 1500m Olympic record, but Ingebrigtsen missed out on a medal, while four women broke Faith Kipyegon's 1500m Olympic record, also set in Tokyo, when Kipyegon won in three minutes, 51 seconds.

Going deeper

The 1500m rivalry between Ingebrigtsen and Kerr has been taken to new heights, even though neither man has won.

The women's 400m final was the fastest ever, with all nine athletes running under 50 seconds. The men's 100m final was the toughest to qualify for in Olympic history; never before had a sub-10 second semifinal time guaranteed a spot.

The final was the closest in history, the only time all nine runners were under 10 seconds in a windless race, and the smallest margin between 1st and 8th place in a World Championship final, with Noah Lyles' gold medal being separated by 0.12 seconds by Oblique Sevilla.

Similarly, the men's 800m final marked the first time that four runners had run under 1 minute 42 seconds in the same race, although no Olympic record was broken in that race.

The 100m final was the only time all nine runners were under 10 seconds in a windy race (Richard Heathcote/Getty Images)

Maurizio Stroppiana is vice president of Mondo, an Italian company that makes synthetic athletics tracks. Mondo built its first Olympic track for the 1980 Moscow Games, 12 years and three Games after the track was first introduced in Mexico City in 1968. Mondo has built every track since the 1992 Barcelona Games.

“Mondo's tracks are known as the fastest in the world, with more than 300 records having been set there, accounting for more than 70 percent of all current records,” Stroppiana said.

With numbers like these, you might say Mondo has figured out the science of building fast trucks, but the science isn't as perfect as you'd expect: Mondo trucks are made from “vulcanized rubber,” Stroppiana says.

When Paris hosted the Olympics in 1924, the stadium was a concrete track “that was almost like dirt,” Stroppiana explains, “so it felt more like running in a field than on a 400-metre (artificial) track, except it was dirty.”

“Fast track” is something of a misnomer. Whether an athlete is fast or not, making the track efficient is what matters. “We're trying to minimize the energy lost. The track compresses[when your feet hit the track]and gives that energy back most efficiently, but some of it is definitely lost,” Stroppiana says.

The 1968 Mexico City Olympics were the first to feature an artificial track (AFP via Getty Images)

When an athlete runs, they generate a vertical force roughly three times their body weight. How much of that translates into horizontal force, or forward momentum, is determined by “braking and propulsion,” Stropiana says.

Mondo implemented “elliptical air cells within the base layer of the truck” and found this had the dual benefit of increasing net horizontal energy return by 2.6 percent and improving impact absorption by 1.9 percent.

The goal is to maximize performance while protecting the athlete, but the two are interrelated: “The track has to provide a certain level of comfort and cushioning,” Stroppiana said.

He explains that the factors that determine maximum energy return are “the type of material, the elasticity of the material. There is an aerosol at the bottom of the truck, which provides extra cushioning and ensures that the energy is returned as evenly as possible.”

“What we noticed on the last track (in Tokyo) was that depending on where the athletes planted their feet, the results varied. We changed the shape to give a more uniform response and also to increase the depressed area of ​​the track,” Stropiana said.

“This makes the track better because you won't feel any difference, and it ensures that the athlete's rhythm is maintained because the elastic response is exactly the same across the entire track.”

That may sound simple, but it's not. “It took us about two years to fine-tune this new solution. We developed the mathematical model at the University of Milan,” Stroppiana says. The model allowed them to run simulations and test new combinations faster; the four-year Olympic cycle provided ideal preparation time.

Track cleaning for the Tokyo 2021 Olympics (Antonin Thurier/AFP via Getty Images)

One of the myths Stropiana wants to dispel is that of track hardness. “This story started with the amazing times at the 1996 (Atlanta) Olympics,” he says. “They started saying, 'Yes, they're fast. They're fast because it's hard.' And we haven't been able to change that perspective ever since.”

How hard is the track in Paris? “It's softer than it used to be,” Stroppiana says. “We really realized that making the track harder is not a good solution, and it doesn't necessarily translate to faster times. In fact, it can lead to injuries. So we've been changing that in the last six or seven years.”

They now use lower carbon production methods and more sustainable materials than before, such as calcium carbonate from mussel shells.

Naturally, it won't be cheap: Stroppiana estimates the cost of the Paris track at “two to three million,” explaining that the composite section on top is “quite thin, only 14 millimeters thick.” Tracks tend to last around 15 years before needing to be replaced or re-laid, he says.

Mondo built the blue track for the Rio 2016 Games (Patrick Smith/Getty Images)

Decades of academic research have thoroughly explained the effects of altitude (positive in sprints because of reduced air resistance, negative in long distances because of reduced oxygen) and wind.

The 1968 Olympics added to the impact of being held at the highest altitude in the history of the Summer Olympics, at over 2,000 meters (7,000 feet). Sprint and jumping records were shattered. Of the 12 sprint events, only the women's 400 meters did not have an Olympic or world record, while the longer distance events were slowed in pace.

Sprints over 1,000 metres are not considered legal and are considered “altitude assisted”, with a maximum tailwind of two metres being the standard for legal sprinting against the wind.

That means a good track needs to be located in the best place to set (legal) records: Saint-Denis, north of Paris, where the Stade de France is located, is less than 50 metres above sea level. Stroppiana says the stadium creates a “microclimate” that “provides more favourable (performance) conditions”.

He explains, “The stadium's structure, including its oval shape and partially covered roof, helps reduce wind interference. The stadium's seating arrangement and the height of the stands help provide some shading from the track.”

In the future, the Olympic Games in Los Angeles, USA in 2028 and Brisbane, Australia in 2032 will both be held in coastal cities.

The Stade de France's “microclimate” provides favorable conditions for fast times (Richard Heathcote/Getty Images)

For Stroppiana, the future of track manufacturing lies in Mondo collaborating with shoe and cleat brands, which “are notoriously secretive about their knowledge. There is now a movement towards open innovation, which means collaboration within the industry, but not through competing brands.”

“I think the next evolution of the track surface is to tailor it to these different (field) disciplines and that's an area of ​​improvement for all runways,” Stropiana said.

He went on to say that Mondo has worked with Adidas, Nike, Asics, ON and Puma, among others, and collaborated with Puma in Paris.

“Before the Tokyo Games, we worked with Asics because they gave us insight. We set up tracks in their lab and they were testing different types, different solutions to see which track works best.

“They will do their own assessment and try to make sure the interaction (between the track and the spikes) is as good as possible, taking into account how the spikes bite into the ground, which is very important.”

Different events require different spike lengths, and Stroppiana says 400m spikes have “different characteristics on the right side,” which makes it easier to run crookedly (as the outside of the foot hits the track first when landing, and the athlete turns on the left side).

There's a trade-off to be made: “Mondo wants to ensure adequate traction but minimise friction, so if the spikes dig too deep into the surface, it will slow the player down,” Stroppiana says. “That's one of the characteristics of the top clothing layer – it needs to be spike-resistant.”

The exceptions are the pole vault and the javelin, where athletes are moving with such force that the spikes need to penetrate the ground to avoid injury.

“In Paris, if you look closely at the javelin runway, the last part is a slightly different colour[to the track],” Stroppiana says. “Why? Because that part is specially designed for javelin throwers. We worked with the German and Finnish teams to test different solutions.” They wanted “a runway with more resistance for the spikes, with more grip,” he says.

“Normally the track has to be the same. You can't have different characteristics in different areas. But for the javelin, they (World Athletics) accepted these changes.” It worked, as Pakistan's Arshad Nadeem threw 92.97 metres, beating the Olympic record by more than 2.5 metres, to win Pakistan's first athletics gold medal.

Stroppiana is optimistic about a future where further adjustments can be made: “For longer distances, we can have specially made sections,” he says, suggesting an inside lane. “In fact, we've built a few tracks like this – not for competitions, but for training. There, you have a different elastic response.”

There's no doubt that the LA track will be even more efficient in 2028. Mondo has four years to test and retest new combinations and spike brands. The main question that remains is what color it will be.

(Top photo: Nathan Lane/Bloomberg via Getty Images)