A recently published study has announced that humans could theoretically run speeds of up to 40 mph.

Currently, the fastest human in the world, Usain Bolt, can run a 100 m sprint at nearly 28 mph.

Researchers announced this groundbreaking milestone after analyzing the factors that affect and limit human speed potential. The research found that the ability to run up to 40 mph could come down to how quickly the muscles in our bodies can move.

Previous studies stated that the major factor limiting human speed was the amount of force our lower limbs could handle, but this new investigation claims that there might be more to this.

The research found that human can handle more impact and force on their lower limbs than previously expected. This was uncovered by having individuals hop on one leg while running top speed on a treadmill that measured force of impact. It was found that force of impact increased by 30% when hopping on one leg as compared to force of impact when running at top speed with both legs. Runners did the same test while backwards running and the force of impact while hopping on one foot was the same as running forward on one leg. Therefore, our limbs can theoretically handle more force than once thought.

This suggests that it is the muscle fibers that affect our speed the most. The researchers have shown that muscle fibers set the contractile speed limits on just how fast our limbs are able to apply force onto 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,” researchers stated.

The conclusions were published in the January 2016 issue of Journal of Applied Physiology.

Source

http://www.livescience.com/8039-humans-run-40-mph-theory.html