We all remember Nike’s Breaking2 project, when Eliud Kipchoge came within 25 seconds of breaking the elusive two-hour mark in the marathon. And that’s not to mention, Kipchoge’s subsequent marathon times which have hovered around two hours—and his 1:59.40 marathon in the INEOS 1:59 challenge. But what exactly is needed from your body to run 26.2 miles in this amount of time?
To understand the physiological demands of that kind of pace, researchers looked at 16 male distance runners who were part of the Breaking2 project.
In a study recently published in the Journal of Applied Physiology, the runners ran increments on a treadmill, with the speed continuously increasing until exhaustion, and ran outdoors on a track, holding a two-hour marathon pace before accelerating to max speed. Researchers measured the runners’ responses to pulmonary gas exchange rate (the flow of air into and out of the lungs, and the transfer of oxygen and carbon dioxide into the bloodstream), heart rate, and blood lactate (a substance made by muscle tissue and red blood cells, which carries oxygen from your lungs to other parts of your body) during this incremental exercise.
They also evaluated runners’ VO2 max (the maximum oxygen delivery and utilization for cardiovascular exercise) and lactate threshold (the point at which the concentration of lactate in the blood begins to increase rapidly).