How many mph is the fastest human

The ground forces applied while hopping on one leg at top speed exceeded those applied during top-speed forward running by 30 percent or more. That suggests our limbs can handle greater forces than those found for two-legged running at top speeds. And although top backward speed was substantially slower than top forward speed, as expected, the minimum periods of foot-ground contact at top backward and forward speeds were essentially identical.

The fact that these two drastically different running styles had such similar intervals for foot-ground contact suggest that there is a physical limit to how fast your muscle fibers can work to get your feet off the ground, the researchers say.

The new work shows that running speed limits are set by the contractile speed limits of the muscle fibers themselves, with fiber contractile speeds setting the limit on how quickly the runner's limb can apply force to the running surface.

In the model, leg length also mattered. Animals with longer legs are able to push their bodies farther forward before their foot must leave the ground, prolonging the time they have to accelerate between midstance and liftoff. Bipedal creatures have evolved with much more rigid spinal structures to prioritize balance and stability over speed. Animals whose trunks are parallel to the ground, however, evolved with more flexible spines that are optimized for prolonged foot contact with the earth.

But what about muscle fatigue? One part of their analysis concluded that any animal can accelerate to at least 90 percent of its maximum speed before running out of fuel. Hirt did not respond to an emailed interview request about this result. When you run down the back straight, however, you spend longer going slower, fighting against the wind.

The difference in the time you spend being assisted by the wind versus the time you spend battling it ensures your lap time always slows. Imagine the extreme example of a wind so strong that it doubles your speed down the home straight. So wind and other adverse weather conditions can act as a leveller, adding to the uncertainty about the results of individual races.

Well, perhaps not. The team concluded that, if trends continue as they have over the last 90 years, women could be dominating the metres by Christian Coleman, however, broke a world record earlier this year for the meter dash, coming in hot at 6. And for the ladies, Florence Griffith-Joyner has the fastest meter at That's 22 MPH! No matter who holds the top spot, whenever I see these outlandishly fast humans, one word comes to mind: how? How can a human be so damn speedy?

But they also have genetics working in their fast-paced favor, says Colleen M. Brough, P. To run at the speeds most elite sprinters do, you need a certain amount of type II and IIx muscle fibers—the fast-twitch ones that provide, quick powerful movements but burn out quickly, says Brough.