Humans Capable of 40mph Run

New research suggests that human beings are biologically capable of running close to 40 miles an hour, a pace that's approximately 12mph faster than Usain Bolt and just 10mph slower than a lion. A man able to run at this speed would cross the finish line of 100 meters as Bolt dawdled at the 60-meter mark, the Telegraph reports. The calculation is based on an assessment of how quickly the muscle fibers themselves can contract.

Scientists had thought the limiting factor in human speed was the amount of force the limbs could take striking the ground, but the researchers from the University of Wyoming say their work shows it's the "speed limit" on the muscles that are key. Their findings are published in the Journal of Applied Physiology.

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