Imagine a landscape as barren and endless as the eye can see. Then imagine that your task is to cross it — on foot, through eye-stinging dust storms, unbearable heat and a body willing you to stop with every step. Welcome to the Sahara. Welcome to your "marathon of the sands."

Aptly named the Sahara meaning "The Great Desert," it is a land mass almost as large as Europe or the United States, making it the largest hot desert in the world, second only to Antarctica. (Antarctica is not commonly thought of as a desert because of its cold climate, but it is classified as such when the amount of rainfall is measured.)

The cheetah is the fastest sprinter on the planet, going from 0 to 60 mph in less than 3 seconds. But what about over long distances? In this incredible video from "Life of Mammals," we see how different animals respond to the challenges of survival that require the use of their fitness and strength.

Even though the human marathon across the Sahara may be less fraught with danger than the journey of pronghorn and the gazelle, the six-day, "ultra-marathon" (the equivalent of six independent marathons) is a feat of endurance. At a total of 254 kilometers (156 miles) long, it’s a task that even the cheetah would find difficult, considering that at its best, the cheetah can only travel up to 460 meters (1,510 feet).

Go humans! And we wish all the competitors the best of luck! 

This originally appeared on BBC Earth and was reprinted here with permission.