The mechanics of speed

Watching Marcus Rashford playing against Tottenham, his additional pace was very apparent.  His anatomical  type is also found in Mbappé and Usain  Bolt for that matter.....very long calves relative to his height.  Which makes me wonder.....is this elongation of the lower leg the key to great speed.

I have found a lot of articles on building calf muscles...none on the pure mechanics of the leg. But almost everybody who is really quick that I can think of conforms to this physical type.

Any thoughts?

mozart you might well be onto something. No getting away from the fact that Bolt was a naturally gifted sprinter with the assets as stated.

But at the same time, guys like "Benzine" Johnson were fast as well as numerous other sprinter users.

"Flow" Jo was another "Speed" merchant that comes to mind.

Unfortunately, the "Docs" in the "Labs" appears to always be one step ahead of the athletic Docs judging from history. 

Sad that performance-enhancing aids are rampant in the sports world today.

It’s not as pronounced on Ben Johnson or Carl Lewis for that matter, but I think still true. A mechanical engineer should be able to model this.

Some of the fastest boxers I've seen have similarly long calves. 

Perhaps there is a correlation with fast twitch and longer muscles. Maybe fast twitch fibres are the most effective in elongated muscles as opposed to shorter and rounder ones.

Greyhounds are faster than more muscular dogs and cheetahs faster than thicker cats.