Geoffrey Mutai celebrates after winning with a course record in the men's division at the NYC Marathon Sunday. (Kathy Willens/AP)

But with Kenya’s marathon men smashing records left and right, the question becomes — could a sub-two hour race be close in sight?

Mutai thinks it’s possible, saying it depends on favorable weather conditions and the shape of the runner. Meb Keflezighi, the top-finishing American, says that “of course” it’s possible, and that he hopes we’ll see it soon. Discovery.com reports that someone is likely to run it within the next 25 years, likely in Berlin or London.

Discovery’s report is based on a 1991 scientific paper by Mayo Clinic anesthesiologist and exercise researcher Michael Joyner, who found that a rise in marathon popularity and therefore wider participant genetic pool, as well as improvements in sports medicine, shoe technology and nutrition have all made the sub-2 hour far closer than ever before.

Joyner’s paper, published in the Journal of Applied Physiology , found that it was theoretically possible to run the race in 1:57:58. A follow up paper of his predicted it would happen within 12 and 25 years.

The top marathoners in recent years have come from East Africa, where many grow up running at high altitude, and so it’s likely the person who breaks the two-hour mark will be East African, too.

Discovery rounds up the essential combination of factors that will likely exist on that record-breaking day:

A high VO2 max: A measure of how good the muscles are at turning oxygen into fuel, like horsepower in a car. The record-beater must not only have a high VO2 max, but also be able to sustain a high percentage of the VO2 max for a long time.

Running economy: The ability to maintain a certain speed for a given amount of oxygen used.

Physical and mental health on the day of the race.

Weather conditions: According to Joyner, it should be a “windless, cloudy, 50-degree day.”

Flat course: This explains why London and Berlin are most likely. NYC, with all its hills, is a long-shot.

In his paper, Joyner had this to say of the sub-two hour race:

Whenever people have attempted to place limits on what humans can do, humans always do a little better. If you make barriers, people are going to try to break them, whether it's going to the moon, flying across the Atlantic, trying to set an age-group record or becoming the oldest person to do something. It's who we are.