How much is biology, how much is physics? How much is inherent ability, how much is technique? Does every individual runner have a maximum possible speed over a certain distance? Basically, what exactly does Usain Bolt do better than anyone else?
In: Biology
There are things people can do to run faster: work on their strength, work on their stamina, lose weight (if needed), and work on their running mechanics to improve their speed and efficiency. Doing all those things will allow a person to reach their maximum running speed.
However, this is where the genetic and body structure aspects others mentioned come in – two people could do identical training regimens, but the one with the ideal genes and structure would have a higher maximum running speed than the one with less-than-ideal traits for running.
So basically, Usain Bolt was already built for speed, and training and practice helped him realize his full potential.
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