Maybe, just maybe, you are already a 5x runner. I certainly can't run any appreciable distance (which I am assuming here as running for just a few seconds isn't interesting) at speeds anywhere close to that... I am the running equivalent of the 0.1x programmer who is super excited by their Excel spreadsheet ;P.

This comparison is not good at all since you're only considering one metric, maybe he's a 10x runner because he has better technique, recovers faster, gets less tired, etc.

It's like comparing developers by how fast they can type.

Yes, this is why I thought the idea of "of course there are 10x developers because there are 10x [other categories]" was not a very useful statement. There are many dimensions to this assertion. In what way is a 10x developer 10x? And furthermore, could it be that there is one single dimension of a certain workflow in which a developer judged not to be 10x is simply fumbling in the dark, only able to work by random trial and error, while the 10x developer has a clear view of? Take two developers with equal aptitude with creating efficient algorithms, fluency in a certain language, facility with dev tools used in that role, etc, but one has no clue about networking concepts. Given a task that involves networking, one may well appear to be 10x the developer, when in fact their actually just an infinitely superior network administrator.

"A 100 mile run can take just 12 hours for the most elite runners and as long as 48 hours for the back of the pack racers. There are so many factors that can vary finishing times."

There are 4X runners I guess.

Most runners can't even finish a 100 mile run. 48 hours isn't the baseline.

Whoever invented the bike, and then the car, airplane etc

So these 10x developers have access to a totally different set of high power tools?

No they think outside the box and have massive leverage through code