Why can’t a human
run as fast as a cheetah?

The cheetah is born with traits that let it run fast. In fact, over a short distance, it can run faster than any other animal. Here are a few of the main reasons.

First, like horses and ostriches, the cheetah has short, strong upper legs and long, thin lower legs. The legs are light in weight, yet they have plenty of strength and leverage to push against the ground.

Second, unlike other cats, the cheetah has claws that do not retract all the way into the paws. The claws can dig in for extra traction.

Third, the cheetah’s spine is very flexible. It bends when the cheetah lands and recoils like a spring when the cat pushes off, so the spine adds force to each leap.

Finally, the cheetah’s nostrils are big. With each breath, the nostrils let the cat inhale plenty of oxygen and exhale lots of carbon dioxide. That keeps the muscles working efficiently.

But humans are better suited for walking on two legs. Our thighs are long compared to the length of our lower legs. And we can’t run well on all fours—so a flexible spine wouldn’t help much, even if we had one. And look at those tiny nostrils! Our bodies are good for staying upright and keeping our hands free for other jobs. But cheetahs are great for speed.