At the Olympic trials in June, American sprinter Sydney McLaughlin broke the women’s 400-meter hurdles world record, finishing in under 52 seconds. McLaughlin broke his own record by almost half a second at the Tokyo Olympics on Wednesday. The next runner to cross the finish line also broke McLaughlin’s June record, but had to settle for the silver.

It was the same story on the men’s side: the winner and the runner-up in the 400-meter hurdles final both broke the previous world record.

These four runners, along with many more this year, wore a relatively new type of shoe known as super pointe shoes.

“If we look at the whole landscape, most people are convinced that these ‘super spikes’ are definitely a factor,” Laura Healey, researcher in Puma’s shoe innovation department, told Insider.

Super crampons are athletic shoes that use the combination of a stiff plate and soft foam to give runners more energy with every step. Nike launched the first such peaks in 2019, forcing companies like Adidas, Puma, New Balance and Saucony to design their own versions.

These new spikes change what’s possible on the track, although it does cause some old and current track stars to worry about the integrity of the sport. Here’s how super tips work.

Lightweight, resilient foam is the key to energy efficiency

In the past, spikes were designed simply to protect the bottom of a runner’s feet and provide traction (spikes, in this case, refer to shoes, not the tiny, pointed pieces of metal of the same name). They were designed to be as light as possible, with almost no foam – “kind of like functional sandals,” University of Michigan athletic performance researcher Geoff Burns told Insider.

This is because the old types of foam were heavy; think of ethylene vinyl acetate which is used in exercise mats, for example. So, every 100 grams of foam meant a loss of energy efficiency of about 1%. But then came new foam formulations like Nike’s ZoomX, which uses polyether block amide, or Pebax foam. Pebax is almost miraculously light.

“It was mind-blowing and allowed shoe companies and scientists to rethink their assumptions,” Burns said. “What a shoe could do for the body has changed.”

The new foam is softer than its predecessors – giving athletes more comfort because it is compressed – and remarkably resilient. Once the ZoomX foam is crushed, it returns to its original shape, restoring 85% of the energy used by the runner to compress the foam. (By comparison, ethylene foam yields between 60% and 70%.)

“That’s why we haven’t seen any great peaks so far,” Healey said. “Before, the foam was not strong enough to merit adding it to the shoe.”

The other key part of super crampons, the stiff carbon fiber or hard plastic plates, help sprinters run on their toes. Most people run from heel to toe, hitting the ground with the back of the foot, then roll forward to push off with the toes. But it’s an energy-expensive process that involves slowing down with every step, according to Kyle Barnes, a marathon runner and movement science researcher at Grand Valley State University in Missouri.

Barnes told Insider that when he tried on Nike’s ZoomX Dragonflys, a super cleat Nike released a year ago, the shoes instead “tipped” forward, causing him to run only on the shoes. toes and mid-feet.

“Like a glorified version of falling from a hill,” he said.

Are the super tips fair?

Since Nike released its first prototypes of super spikes in 2019, runners using the shoes have broken records in the 1,500-meter, 5,000-meter and 10,000-meter events, Outside Online reported. Although other brands are now using similar models, some athletes are still concerned that Nike shoes give an unfair advantage.

After Norwegian sprinter Karsten Warholm won the men’s 400-meter hurdles event in Tokyo, he criticized his American opponent Rai Benjamin – who placed second – for wearing Nike Air

Zoom
Super Maxfly tips. The Maxflies have a component Nike calls a “Zoom Air unit” under the forefoot: an elastic, flexible cushion that helps runners conserve more energy with every step.

Warholm, which is sponsored by Puma, called the technology “bulls —“, comparing soles to trampolines and saying the shoes take away credibility from the sport.

Healey said that although Warholm’s Puma super spike has a carbon fiber plate similar to Nike’s, Nike’s air unit “has a higher energy return than foams, and Nike has patented this technology. “.

Nike, meanwhile, told Insider that the same three components – carbon fiber, foam and air – have all been used in running shoes for decades, both Nike and others.

“We’re just smarter about the way we design and assemble them,” the company said.

Usain Bolt also complained about the super spikes, although he didn’t specifically call Nike. Bolt, who won the men’s 100-meter and 200-meter sprints at the 2008, 2012 and 2016 Olympics, said the super spikes give current runners an advantage over previous record holders.

“It’s strange and unfair for a lot of athletes,” Bolt told Reuters.

None of the super cleats used at the Tokyo Games break the rules, according to guidelines from World Athletics, the international athletics governing body.

Burns said super-spike technology probably mattered less for shorter races, including the 400-meter, because fuel efficiency is less of a factor when a race ends in less than a minute.

“The sprint is limited by the absolute power output,” he said.

Nike spikes could be 2% more effective – but other shoes are in the same stadium

According to Burns, Nike’s super cleats are essentially clean versions of the company’s hit Vaporfly shoe, which has changed the marathon world over the past five years.

“It’s the same basic recipe,” he said. “They took their lessons from the road shoe and adapted them to the track.”

The Vaporfly are the road racing versions of the super crampons – they also have a stiff plate and resilient foam. A study funded by Nike by independent researchers found that shoes impart about 4% more energy efficiency per step. Athletes using Vaporflys dominated the Rio Olympics in 2016, as well as all major long-distance road races afterwards.

Competing companies struggled to catch up with Vaporfly technology, and then had to do it again after Nike released its first super peaks. Burns believes the one-year delay in the Olympics has given these competitors time to catch up.

“If the Olympics had been held last summer it would have been a joke,” he said.

Nike spikes don’t come with a specific number like the Vaporfly’s 4% energy savings, as that number was calculated based on the amount of oxygen athletes suck in and the carbon dioxide they suck in. ‘they release. This measurement no longer makes sense when runners switch from aerobic exercise – which uses oxygen – to anaerobic work, which it does not. Almost all sprints are anaerobic.

Still, Burns estimated that Nike’s super spikes could confer an energy advantage of 1.5% to 2%.

“When I look at the result of the 1,500 meters, deep inside I think two to three seconds faster,” he said, adding: “I hate to say it, it kind of became a race. to armaments. “

Nike, for its part, said runners’ achievements were never just about their shoes.

“Time and time again, we’ve proven in our labs that Nike running shoes and crampons deliver measurable benefits, but ultimately it’s the athletes on the track and on the roads that validate our work,” said the society.

Many athletes win medals by wearing non-Nike shoes. In Thursday’s 110-meter hurdle race, runners wearing Puma, Adidas and Nike took the top three spots – in that order. The winner of the men’s 400m wore Adidas cleats and the winner of the 200m wore Pumas. When she broke the world record in the 400-meter hurdles, McLaughlin wore New Balance.

Healey said there are plenty of new super tips that give Nike a comparable advantage.

“It doesn’t look like all Nike shoes are on the catwalk,” she said. “We are in a new era of super spikes.”