How Far Can Humans Run?

Niko McCarty
5 min readFeb 23, 2019

Cliff Young and Dean Karnazes May Set the Limits.

A professional relay race. Photograph by Thomas Wolter.

You were born to run barefoot, with nothing consoling your feet from the harsh earth. Your DNA was made for this. Your ancestors chased, hunted and outlasted even the most rapid of prey. Gazelles, horses, elk: nothing was a match for the upstanding bipeds.

Somewhere along the way, humans relinquished their genetic fabric. We displaced what made us human in the first place. We stopped running extraordinary distances. We no longer had to chase prey, instead opting for long-range projectiles and clever traps. Our intellect replaced our physical prowess. And yet, we still hold tight to the unique attributes that made us such great long-distance runners in the first place. We dissipate heat by sweating and the shape of our feet — and small toes especially — nearly “double the mechanical work of the foot”, according to a study in the Journal of Experimental Biology.

But not all is lost and there are still those that can run extraordinary distances. Over the last two hundred years, humans have time and again returned to their roots. We still run marathons, a race inspired by the story of a Greek soldier, despite it being invented for the 1896 Olympic Games.

We don’t just run against other people, either. In 1818, an Englishman bet a friend that he could beat a horse in a 48-hour race. He lost (running 158 miles vs. the horse’s 179), but the obsession with long-distance running never faded. By 1880, during a 6.5-day long race of man vs. horse held in Chicago, a man named Michael J. Byrne successfully ran 578 miles against a horse, beating it by 15 miles.

In the 21st century, people have continued to stretch the physical limits of their endurance, displaying their feats in international competitions. The Badwater 135 is a 135-mile race through Death Valley, held in the climax of the desert heat. The Barkley Marathons are a grueling, 100 mile race with 54,200 feet of vertical climb (the height of Mt. Everest…twice) through Frozen Head State Park, which must be completed in 60 hours. The Marathon des Sables is a blistering 156-mile race across the Sahara Desert.

Niko McCarty

Science journalism at NYU. Previously Caltech, Imperial College. #SynBio newsletter: Web: