Usain Bolt, the fastest ever human, could comfortably outrun a Tyrannosaurus rex, according to scientists from the University of Manchester. In fact, so could many amateur athletes, with new research suggesting T-rex was physically incapable of running because of its size and weight, and would have broken its legs had it tried to break into a sprint.

The Cretaceous-era carnivore is considered one of the most fearsome creatures to ever walk the earth. But it turns out “walking” is all it could muster, according to Professor William Sellers from the School of Earth and Environmental Sciences.

“The muscles need to be able to generate sufficient power to allow high speed locomotion, but at the same time the skeleton has to be able to cope with the loads generated by the high speed – and this is where it fails. T-rex’s skeleton is simply not strong enough for running locomotion,” said Sellers.

bolt vs t-rex

The big fella may not run fast but his chompers are still lethal.

Researchers used an engineering technique called multibody dynamic analysis, coupled with machine learning, to produce what they say is the most accurate simulation of T-rex’s gait and biomechanics to date.

The new research concludes that T-rex was limited to walking speeds of about 5m per second, equating to 18km/h – less than half the speed of Usain Bolt’s personal best of 44km/h.


The running ability of T-rex has been hotly debated among palaeontologists for decades. But the consensus based on previous biomechanical models was that the dinosaur could manage speeds anywhere up to 75km/h. A study published in the Royal Society’s Biological Sciences in 2007 suggested a more conservative top speed of 29km/h, but this would have still been fast enough for T-rex to chase down many modern-day runners, especially over long distance.

bolt vs t-rex

Eat my dust, dinosaur!

Sellers said previous methods for analysing locomotion of fossil animals may have been “over-simplified”.

“Animals are a mechanical system with many different components working together to produce the desired outcome. You need to consider all the important mechanical processes when assessing athletic ability,” he said.

Sellers believes the study forces a re-think on how this supposedly ferocious carnivore caught its prey.

“It certainly would not have been able to chase down faster moving prey animals,” said Sellers. “That leaves other hunting options such as ambush, and of course it means that ideas such as ‘T-rex the scavenger’ have to be reconsidered.”

The research, published in the scientific journal PeerJ, states running at high speeds was probably highly unlikely for other large two-legged dinosaurs such as, Giganotosaurus, Mapusaurus, and Acrocanthosaurus. – Reuters