It’s easy to understand why running fans almost missed one of the most epic marathon performances ever last weekend. All eyes were focused on Eliud Kipchoge’s two-hour, barrier-breaking effort in Vienna—plenty of U.S. fans stayed up well into the wee hours on Saturday night to catch it, in fact. When the 34-year-old runner from Kenya hit 1:59:40, it seemed as if the sport had used up all its mind-boggling performances for one weekend.
Then 25-year-old Brigid Kosgei from Kenya set off at a screaming pace on Sunday at the Chicago Marathon, and runners the world over began to sit up and take notice. She passed the 5-kilometer mark at a pace that would have put her across the finish line at 2:10:31. Those paying attention were rewarded with another—and some would argue equally more important—barrier-breaking marathon performance. Kosgei ultimately crossed the finish line in 2:14:04, shattering Paula Radcliffe’s 16-year-old world record of 2:15:25.
“I did not see this coming,” said Steve Magness, performance coach and author. “Paula’s record stood for so long and it was a minute-and-a-half faster than the next-closest performance (Kenyan Mary Keitany) that Kosgei caught me off guard.”
For Magness and others, like Dr. Michael Joyner, a Mayo Clinic physiologist, Kosgei’s world record is equivalent to, or better than, Kipchoge’s sub-2:00 mark. Joyner and two colleagues, in fact, did the math back in 2015 that showed Radcliffe’s 2:15:25 marathon time from 2003 had already achieved the equivalent to a men’s two-hour marathon. So by those measures, Kosgei blew it out of the park.
How it played out
Alison Wade, author of the weekly newsletter Fast Women, said that while Kosgei’s record was unexpected this past weekend, it makes sense. “Given the big jumps men have been making at the marathon distance, the women were due for a breakthrough, too,” she said.
Several factors likely led to Kosgei’s performance. First—and the factor everyone is talking about—are the shoes. Like Kipchoge, Kosgei donned the latest Nike iteration of its performance-enhancing marathon shoe, dubbed the ZoomX Vaporfly Next%. “There’s no question the shoes are changing the marathon,” said Magness. “We see it with elites and sub-elites.”
While the shoes may give anywhere from a 1.1 percent to 5 percent performance boost thanks to their carbon-fiber plates and thick, light foam soles, other factors aided Kosgei in Chicago. “When you look at the big, fast marathons from this year, there really weren’t many where females focused on breaking records,” Wade said. “Rather, the women were focused on competition.”
Wade made her case with London, where the field was big and competitive, making the time on the clock less important. In New York last year, the second half was speedy for the top women, but that followed a slower first half. “In Chicago, Kosgei really didn’t have too many competitors to worry about for the top spot, so she was freed up to go for the record instead,” said Wade.
And go for it she did. Kosgei’s first 5K was a 15:28, leading to speculation that she’d implode. But with the help of two pacers through the 30K mark, Kosgei held on with her nearest competitor, Ethiopia’s Ababel Yeshaneh, more than six minutes back.
Wade said another telling sign that the marathon record was ripe for the taking can be found in performances at shorter distances. “There have been big breakthroughs in women’s performances at most of the other distances,” she said. “We just hadn’t seen it yet in the marathon.”
The weather in Chicago was just about marathon picture-perfect, too, and the flat course lends itself to speed. When you take all the factors into account, perhaps no one should be surprised that a 2:14:04 was possible.
While Kosgei’s agent, Federico Rosa, has been associated with Kenyan athletes who have been suspended for doping, Kosgei herself has never thrown a positive test. In fact, she trained in different camps than those who have.
If nothing else, Kosgei has demonstrated that we haven’t seen the fastest women’s marathon yet. “We’re starting to see what happens when women are given opportunity,” said Joyner. “Thanks to Title IX, the talent pool is expanding and women are catching up with performances like this.”
Magness foresees another women’s marathon record drop before terribly long. “If Kosgei can do that with a too-fast first 5K and only two pacers, I think a 2:13 could happen soon,” he said. “If a female is given conditions that mimic Kipchoge’s, who knows?”