The Science Behind Nike’s Breaking2 Attempt

There’s a massive science experiment about to commence in Monza, Italy, that has been four years in the making. That’s how long the 20-plus person science, research, and coaching team at Nike has been sweating the variables of how to get an elite athlete to run 26.2 miles in under two hours.

And there are many, many variables. Pacing and strategy, apparel and footwear, and of course, the mental game. Nike is adamant that the Breaking2 project is not about seizing a record — in fact, some of the factors they’re manipulating disqualify the attempt from an official world marathon record — but about creating the perfect circumstances to find out what the true limit of human potential really is. “Why didn’t we just do all of this in a regular race?” asks Brett Kirby, lead physiologist at the Nike Sport Research Lab. “Because we know what happens in a marathon; these guys do that all the time. This is the new experiment. Focusing on the human without worrying about outside factors.”

By twisting every dial in the athlete’s favor, could Lelisa Desisa of Ethiopia  Eliud Kipchoge of Kenya, or Zersenay Tadese of Eritrea — or all of them — do what most running experts say is all but impossible? Here’s how Nike has engineered the odds in their favor.

Set the perfect pace.

We don’t actually know what it looks like for an athlete to push all-out in a marathon. No one has gone from the gun as hard as they can, the Breaking2 team argues, because the lead pack is always watching each other, and curbing their efforts accordingly. They’re racing to win — not to run their absolute fastest.

For Breaking2, Nike will change that: A group of 30 elite runners will act as “white rabbits,” with six pacers running in a triangle formation around Desisa, Kipchoge, and Tadese at all times. The pacers will run only two laps of the 2.4k Formula 1 track (so, three miles), then they’ll be switched out with fresh pacers. The objective is two-fold: Allow the pacers to block wind resistance and create a draft, and give the three athletes a perfectly consistent 4:33-per-mile pace to hit. As Paula Radcliffe, the record-breaking women’s marathoner explained, “To break two hours, they’ll essentially need to redline the entire time, but not push so hard that they can’t sustain it.” Pacers will ensure that happens.

But the switching in-and-out of fresh runners is also the factor that worries Brad Wilkins, director of the Nike Explore team at the NSR lab, the most about the attempt. “It’s a dynamic strategy, and the timing has to be spot on,” Wilkins says.

Because the International Association of Athletics Federations (IAAF) doesn’t allow pacers to be changed out during a marathon, the pacing model is also one reason why the Breaking2 attempt won’t be eligible for a world record. Says Wilkins, “World record or not, we hope this paves the way for those in official marathons to have a shot.”

Dial in the shoes and kit.

All three runners will wear customized versions of the Nike Zoom Vaporfly Elite: the stitching of the knit upper, the stiffness of the carbon-fiber plate in the midsole, and even the amount of proprietary ZoomX foam — which is supposed to return 85 percent of the energy of striking the ground back to the runner, versus standard sneakers’ 60 percent return rate — will all be exactly tailored to what works best for the three athletes based of 3D foot scans. In company-wide and independent tests, the Vaporfly Elite shows a 4 percent improvement in running economy. (The best part about all of this innovation, the Breaking2 team assures the scrum of reporters in Monza, is that it will trickle down to the average runner; the elite shoe’s commercial version will be available in June.)

For apparel, the Nike team aimed to knock down common problems. Number one: they found the athletes would sweat one to two liters an hour during training, and the moisture would collect in their clothing and weigh them down. Solution: Create a whisper-weight singlet fabric that cools and wicks faster. Problem two: the men’s legs, no surprise, got fatigued toward the end of a race. So the team designed compression tape to be placed strategically on the shins (parts of the body that are moving the most and working the hardest) to support the muscles and further cut wind resistance. Custom compression arm sleeves provide the same support and streamlining benefits, and also simply keep the athletes warm. For men who typically train in 80-plus degree weather, the 50-something temps ideal for the Breaking2 attempt feel especially cold.

Instill utter confidence.

“To tell an athlete they’re capable of breaking two hours is one thing, but they have to believe it,” says Matt Nurse, vice president of the Nike Sport Research Lab. Which is why the company invited Desisa, Kipchoge, and Tadese to its NSR lab in Beaverton for a battery of physiological tests to help dial in their performance. Using the results, the team showed the men that, mathematically, psychologically, a human should be able to run the race in under two hours; more important, each one of them should be able to do it.

Believing that data has given the athletes the mental tenacity essential to making the moonshot a reality. “All three athletes absolutely believe that they can run a marathon tomorrow in under two hours,” Nurse says. “To believe that, you also have to be a bit of a rebel, and have a confidence that’s contagious.”