How Fast Can a Human Run?

The idea that the reason we can skate faster than we run has something to do with how long we are in contact with the ground is ridiculous.

Thought this had recently been answered: bouncier sneakers.

If more legs are better, why no mammals with six legs?

Usain Bolt's speed is not zero at the finish line.

Don’t feel so outclassed, fellow humans. We are pretty good endurance runners. Humans can run a marathon faster than nearly any other mammal and can even run 50 or 100 mile ultramarathons. I think it’s because no other animal is crazy enough to try but still—

This is an artificial construct because it assumes speed is important for survival when fact it is obviously not that important for evolving. As other comments have suggested we acquired significant advantages standing upright that contributed more to our evolution than speed. Once again I fear we are introducing artificial selection rather than Mother Nature’s natural selection... she clearly selected us for other advantages and couldn’t care less how fast we are...until she unleashes the zombies of course.

If running on four limbs has an obvious speed advantage, why did our ancestors evolve to have only two? Speed is such a rudimentary advantage that benefits nearly every organism. For example, a lion would probably have more successful hunts if they were faster and prey such as gazelles would be better off if they could outrun their predators. Cavemen should have evolved to run faster to hunt better and so forth. But humans, arguably the apex predator of our time, are actually pathetically slow compared to the majority of animals. Nearly any dog will be able to outrun an average human and not even break a sweat. This lead me to questioning the advantages of bipedalism and why we were cursed with the max running speed similar to that of a reptile. A simple Google search revealed that running on two feet frees up the two other limbs to utilize tools, forage, and become proficient in giving body signals. Standing on two feet also gives us a height boost, allowing us to see further ahead for increased geographic awareness or potential threats. The differentiation of our hands from our feet give us the ability to engage in fine motor skills such as texting and sewing. Imagine trying to patch a hole in your shirt with your feet! Perhaps what we lacked in speed we made up for through intellect and intricacy, which undoubtedly contributed to our success as a species. But I can't help but wonder why we are so slow.

If running on four limbs has an obvious speed advantage, why did our ancestors evolve to have only two? Speed is such a rudimentary advantage that benefits nearly every organism. For example, a lion would probably have more successful hunts if they were faster and prey such as gazelles would be better off if they could outrun their predators. Cavemen should have evolved to run faster to hunt better and so forth. But humans, arguably the apex predator of our time, are actually pathetically slow compared to the majority of animals. Nearly any dog will be able to outrun an average human and not even break a sweat. Perhaps what we lacked in speed we made up for intellectually and contributed to our success as a species. But I cant help but wonder why we are so slow.

Bicycle, anyone?

It would be interesting to see if a trained sprinter, with a pair of strong poles in their hands, could coordinate some extra locomotion by pushing with arms between pushes from the legs.

What ARE you going to do with all those boats?

I’ve always thought a “Fosbury” moment could occur with long jumpers. Sprint down the runway, hit the board & launch forward headfirst, tuck, somersault and open to land on the feet.

The question is 'How fast is it physically possible for a human to run?' but the answer acts as if it the question was 'How fast is it physically possible for a human to run if a human was a horse?'

I didn't know Randall Munroe wrote for the New York Times! I love his books. Great story!

Interesting. I thought this was a different approach, which would be to guess the maximum number of fast twitch muscles, and how strong they are to relative weight of the body v the weight of the leg muscles. Other things might contribute, like the positioning of the upper body, how hard to pump the upper arms, and so forth. As I understand it, the relative difference between fast and slow twitch muscles is more important than most other factors. And this is dealing with reality. Four legs isn't.

I misread the headline at first and thought it was "How Fat Can a Human Run?" I'm interested to read that article. Given it's resolution season, I bet others would, too.

I have noticed while watching my greyhound run that it is not only her four legs that give her superior speed, but also the flexing of her spine that gives her extra power and spring from her rear leg strides. She also propels herself forward with intermitant strides from her front legs, as is the case with a cheetah. Other dogs do not flex their spine while running as much as greyhounds.

No real need to focus on 2 vs 4. A quick look at the times for officially sanctioned mile runs shows something quite remarkable: the record times over the last 100 years are showing a linear decrease! Several interesting observations come from these data. First, they stop at 1999: no new records have been set since then, the official reason is that the mile is no longer considered an international event. This argument is patently false since the same pattern is seen in the 1500 meters, with the last record in 1998. In fact the real reason will be made clear below. Second, the best-fit linear equation shows a steadily decreasing time, so it is not hard to estimate when the record time will become zero. For the mile the best fit is after 613 years, while for the 1500 it is 667 years. So, sometime between 2665 and 2712, we will acquire the ability to travel at infinite speed, and the universe will become ours. No spaceships will be needed as we can start running and be at our destination before needing to take a breath. Now, we understand why this has been suppressed: some government agency has clearly become concerned that, if this leaks out, funding for all forms of space flight will be eliminated as unnecessary. In fact, the recent ending of the shuttle program suggests that this process has already started. Maybe the real goal should be a massive infusion of funds into support of distance runners, so that we can reach the stars sooner.

That the advantage of four legs is being able to have more contact with the ground reminds me of the innovation in speed skating - the clap skate. The blade is hinged at the front allowing it to keep in contact with the ice longer at the end of the stride. That was the idea, but I seem to remember that the real advantage came from the placement of the hinge and not just the increased time. Comparing skating and running, though, another big difference is that skates slide along the ice during the stride whereas the foot has to stop at some point. The fact that skaters can keep increasing their speed past the 100 meter point points to this advantage.

My 9 month old Labrador puppy can easily run 35 mph. Her four legs definitely give her the advantage. I need lots of tasty treats to keep her from taking off from me on our runs.

Hi folks, according to Wikipedia, kangaroos can top 44 mph (71 km/h). They use two legs and they hop. Whilst we are at it what if some trained from a very young age to roll as in cartwheeling? Back to the drawing board.

Well, who 52 years ago would have thought high jumpers would be flopping backwards over the bar? The "Fosbury Flop" uses superior physics in a counterintuitive way. I can just see all the nerdy engineers training their toddlers to run on all fours, dreaming of Olympic Gold.

Anyone else ever dream of running on all fours? Pushing off the ground and basically tearing into the grass to get more momentum? I've had this as a recurring thing and heard others say that they have, too.

In Lope N.P. in Gabon, a young male gorilla overtook our rather fast-moving Land Rover and kept pace with it for a while. I envied him his quadrupedal stride. The problem seems to be not with our legs or hips, but with short arms.

I have a better idea on how to keep at least one leg engaged at all times and thereby go faster -- buy a bicycle!

This doesn't explain how the ostrich can run so fast.

If how long you had contact with the ground were the determining factor in how fast you could move, then walking would be faster than running! This is actually a topic that has been studied in great depth in animals and I'm surprised this article doesn't cite any of this literature. I've been involved with horses and with racing dogs (whippets, not greyhounds) all my life and I've looked at many slow-motion analyses of their strides. The fastest animals (race horses, racing dogs, cheetahs) have a double-suspension gallop. This means that they lose contact with the ground at two points -- the extension phase (front legs straight out in front, back legs straight out in back) and the collection phase (all legs gathered underneath). This allows them to flex their spines like a giant spring so that they can explode into the air off the power of their back legs. We don't flex our spines when we run and we don't launch ourselves into the air from both back legs. That's why we're so slow.

So much for Desmond Morris's ludicrous claims that humans became hairless to allow us to run faster.

I can't run on all fours but I usually end up that way when I'm done.

I often have a dream/s where I am moving, running on all fours, under various circumstances. And let me tell you, Im killing it in that dream. Fast and covering large tracts of ground. Dont know what that means in a dream, but I love the feeling upon waking.

This article confirms my amateur attempt to explain running using mathematics. What I found was there are three phases in running steps: Acceleration, being airborne, and deceleration. Acceleration throws the body into the air where it is not touching the ground. When landing, there is a deceleration to maintain stability. During running there is braking on every landing. Runners who are able to brake less on landing can run faster. It is also interesting to have observed that runners lean forward when running and lean backward when slowing down. This is related to the vectors that are explained in physics. While trying to determine the fastest pace is interesting, it is even more interesting to understand the mathematical description of running.

What’s all the fascination with running fast? My mantra is to start out slow then tapper off. Makes for the smelling of more roses.

Gosh! This is essential information that I need for daily life. Thanks NYTimes.

How about an exoskeleton to make it possible for us to transfer force from all four limbs in running? Could be an efficient - and more terrain-independent than a wheel - way to get around. Sounds like fun, too.

People can outrun horses over distance. A very fit runner can run down a horse though it may take hours. We hunted by outlasting our prey ,running them to exhaustion . Sure that's not speed as discussed in this article but our two legged stride is built for distance not speed. This is how we conquered the mega- fauna of earth , and fed ourselves . Yes when we developed weapons they helped but we had to run animals down in order to get close enough to use a weapon.

The reason that humans can't run as fast as other animals is a simple one. Humans don't need to run fast. Our advantages are not in speed but rather in endurance and cooperation. Persistence hunting clearly demonstrates the differences between bipeds and quadrupeds. Quadrupeds can achieve more speed but at the expense of energy and endurance. Humans are more efficient allowing evolution to abandon traits that are essential to the survival of non humans.

As the atmosphere and oceans heat up does that in turn heat up the land mass? And how does the heat from the earth's molten core impact on ocean and atmospheric changes in temperature? As the molton core cools will that offset temperature changes due to greenhouse gases?

Humans were built for endurance, not necessarily speed. We used our brains to hunt in groups, and followed animals (who were much faster for short periods than us) until they were exhausted. And human gait is far more complex than is depicted in this article. We are not adding more joints or longer limbs....we simply get in a car and go much faster than almost anything else on our planet.

I am a rower. When rowing, 1/3 of the stroke time is spent actually propelling the boat with the oars in the water while 2/3 of the time is spent getting the oars back, through the air, into the water. A while ago, the Russians came up with the idea that in an 8 man boat with 4 oars on the port (left) side and 4 on the starboard (right), they would do better if 2 pairs (4 oars) were in the water working while the other 2 pairs were in "recovery" - getting back to the start of the stroke. This necessitated lengthening the boat to accommodate the different positions of the hands during the stroke (when all work together, the hands can be close to each other). All in all, the experiment was a disaster! I think the same may happen with humans trying to run in the "crawl" position - our mechanics have evolved to the biped and we'd have to rearrange our joints sort of as the cartoons in the article suggest.

Seeing Randall Munroe post an xkcd What If style article in the NYT is exactly what we all needed. Hope to see more of these in the future!

This leads to another question, how fast a human can move using a mechanical device? Like a bicycle or a device specifically designed for this purpose, maybe something with a giant wheel that one can fully run on.

This leads to another question, how fast a human can move using a mechanical device? Like a bicycle or a device specifically designed for this purpose, maybe something with a giant wheel that one can fully run on.

Fascinating and funny. Of course, growing your legs or hips is not an option but I can find a better pair of sneakers. What should I look for to - increase my speed? make it more comfortable? for long distance running? and long walks?