[adrianN]

Most people don't want to be able to run 10k+, they want to stay healthy. Sports is fun as a hobby, but not everyone wants to have that hobby.

[ck2]

This kind of research allows people to think working out for only a couple minutes is okay if you do it hard.

I think many people could easily train to do 5k and then 10k and get many benefits. Our very evolution came about from persistence hunting which means many people should have the genetics for endurance and far fewer for intensity (speed).