Theory: Man could run 40mph

Updated January 23, 2010
Humans Could Run 40 MPH … in Theory


Humans could perhaps run as fast 40 mph, a new study suggests. Such a feat would leave in the dust the world’s fastest runner, Usain Bolt, who has clocked nearly 28 mph in the 100-meter sprint.

Reuters/Dominic Ebenbichler

Usain Bolt of Jamaica sprints to the finish to win in the men’s 100 meters final during the world athletics championships at the Olympic stadium in Berlin.
Humans could perhaps run as fast 40 mph, a new study suggests. Such a feat would leave in the dust the world’s fastest runner, Usain Bolt, who has clocked nearly 28 mph in the 100-meter sprint.

The new findings come after researchers took a new look at the factors that limit human speed. Their conclusions? The top speed humans could reach may come down to how quickly muscles in the body can move.

Previous studies have suggested the main hindrance to speed is that our limbs can only take a certain amount of force when they strike the ground. This may not be the whole story, however.

“If one considers that elite sprinters can apply peak forces of 800 to 1,000 pounds with a single limb during each sprinting step, it’s easy to believe that runners are probably operating at or near the force limits of their muscles and limbs,” said Peter Weyand of Southern Methodist University, one of the study’s authors.

But Weyand and colleagues found in treadmill tests that our limbs can handle a lot more force than what is applied during top-speed running.

What really holds us back

Their results showed the critical biological limit is imposed by time — specifically, the very brief periods of time available to apply force to the ground while sprinting. In elite sprinters, foot-ground contact times are less than one-tenth of a second, and peak ground forces occur within less than one-twentieth of that second for the first instant of foot-ground contact.

To figure out what limits how fast we can run, the researchers used a high-speed treadmill equipped to precisely measure the forces applied to its surface with each footfall. Study participants then ran on the treadmill using different gaits, including hopping, and running forward and backwards as fast as they possibly could.

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.

New speed limit

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.

“Our simple projections indicate that muscle contractile speeds that would allow for maximal or near-maximal forces would permit running speeds of 35 to 40 miles per hour and conceivably faster,” Bundle said.

While 40 mph may not impress the cheetah, the world’s fastest land animal reaching speeds of 70 mph (112 kph), it’s enough to escape a grizzly bear and much quicker than T. rex, which may have reached 18 mph (29 kph) during a good jog.

The results were published in the Jan. issue of the Journal of Applied Physiology.

Enough already. Can we put a gag order on these bloody treadmill researchers?

I’m sure Michael Phelps could swim 100mph down a waterfall too!

Hater… :slight_smile:

Charlie and I and James just watched an episode of The Office and Michael was clocked running 31mph…so maybe the researchers saw this show and are on to something that coaches do not know about yet.
Plus my doctor said my speech pattern in his office the other was in excess of 40mph (possibly stress) so it seems very likely with maybe some training I could transfer this pattern to leg speed with a bit of help from Charlie now that we know this. Good news! I know believe everything is possible.
Come on Number Two we all know Mr. Phelps was breaking rules to win. He probably trains at Niagara Falls ( Canadian side eh)

Okay KK and Ange. You forced me to turn over my secret video footage of the research facility where this study took place. You can tell it was secret footage due to the poor video quality. The evil laugh in the background is obviously Weyand cackling away, knowing that he did not satisfy the ethics requirements for this study. The subject was obviously a Guantanamo Prison transfer (named Nevar Bin Trainen). Watch closely as he jumps off the treadmill right at about 40mph. Very cruel…

The second video clip shows how the female subjects performed. Obviously, not close to the 40mph velocity, with violent results.


I also know that KitKat has also been conducting his own treadmill testing at his home research facility. Sorry KK, but I had to leak this footage that you recorded with your prize subject detailing the impact forces of running on a treadmill. What a conspiracy!

SUCK IT Weyand. KK has obviously shown that peak forces can exceed 1,000 pounds per stride!

When I’m not wearing my kilt I like to dress down. Where’s the crime in that…

Thankyou for the attrocity report…you sicko

By the way, got any more…very funny

Many different takes on this research. However, all researchers seem to be arriving at the same conclusion: “Don’t mess around with treadmills!”

African American Researchers:

Japanese Researchers:

And, of course, the Saudi Arabians:

Then there’s the treadmill hurdles race

Yes, I’m convinced Liu Xiang hurt himself doing this prior to Beijing in 2008. :slight_smile:

Exactly. You are too spooky.

Or is this that secret film of him training for his comeback?

One and the same!

Dis is gettin stupider and more stupider…

But how about this for a set today:

400m training

350m in 41sec
8mins rest
320m in 41sec
8min rest
300m in 41sec

The Japanese are by far the best at this treadmill game.
Very entertaining #2.
My breathing pattern has normalized!