WHEN ELIUD KIPCHOGE crossed the finish line of the Berlin Marathon in 2:01:39 last month, he didn't just beat the world record—he smashed it by 78 seconds, the largest improvement over the previous record since 1967. After that stunning achievement, it's time to consider whether the once unthinkable is possible: Will a marathoner break the two-hour barrier?
After Berlin, 99 seconds separate the world record from the two-hour mark. While there are still plenty of skeptics, in a 1991 paper Dr. Michael Joyner, a physiologist at the Mayo Clinic, argued that a 1:57:58 marathon was theoretically possible for an ideal runner, for instance someone with a high level of maximum oxygen consumption. Last year Nike organized an attempt to break two hours in a controlled environment—nearly perfect weather conditions, an alternating cast of pacers and special shoes supposedly engineered to offer a 4% benefit in running economy—and Kipchoge came up short, running 2:00:25 on a flat Formula 1 course in Italy. (The attempt wasn't eligible for the official world record.)
Kipchoge, 33, has won 11 of 12 career marathons, and it's likely his mark will stand for the foreseeable future. "I think Kipchoge is the greatest we've seen, and I think [his record is] going to be hard to beat," says Alex Hutchinson, the author of Endure: Mind, Body, and the Curiously Elastic Limits of Human Performance. "But I also think that whatever someone does, sooner or later someone else comes along who can do it better."
In other words, as Hutchinson argues in his book, endurance is as much an exercise in mental drive as it is in physical capacity. So as the record inches closer to two hours, reaching that milestone becomes increasingly attainable. Joyner, for one, is bullish. "If I was in Vegas," he says, "I'd put the over/under at 2028 or 2029."
FOR THE RECORD
The two-hour marathon isn't the only fabled milestone of human endurance.
In the women's mile
Svetlana Masterkova set the bar at 4:12.56 in 1996. Two women have eclipsed 4:15 in the last three years.
In the men's 400-meter sprint
Running 100 meters in 10 seconds is hard enough. Could someone do it four times? The record is 43.03.
In the decathlon
A perfect score is close to impossible. The current standard—set the same day as Kipchoge's mark—is 9,126.