Why do elite runners run high mileage? Dont they already have good enough aerobic fitness?

That they don't already have good enough aerobic fitness,

Why do musicians practice? Why do Dr.’s continue to learn about medicine?

What you don't use, you lose. Which is why there are things such as periodization and peaking.

They do it because they can, and it works. You should try it sometime.

The talent of elite runners is, that they can do high mileage without getting injured.

To stay elite runners........

They do because they ( or their coaches) don't know how to reach top elite performance on low mileage.

Even if running at a high level comes down to something like 75% talent 25% hard training, you take 15-20% of that 25% away and a 12:50 5k athlete turns into a 15:00-16:00 5k athlete

This is a basic training physiology question disguised as a question about professional runners

lol i wish most doctors would stay up to date

An understanding of what running fitness is.

If a guy with 12:50 ability actually comes out for the sport, he’s not going to run 15:00-16:00. You say talent and training are 75/25%, but to reach the highest levels it’s not possible to do so without the necessary talent. Meanwhile, anyone can train hard.

There are thousands of runners that can train hard and avoid injuries, but a tiny fraction of a percent go on to become elite. Hard work is nothing without talent. I’ve known runners that did 100mpw for years after college, just to run a marathon OTQ. In college, there were heavy mileage guys that hovered around 14:30. The talent of an elite is proportionately long legs, a high VO2Max, an efficient stride and the right combination of fast/slow-twitch muscles.

I've always kind of felt that for anything 5K or lower... guys could be pretty much as good on really high quality lower mileage (50-70 mpw) if they are uber talented and watch their diet...

But for elite runners... there is no point in training that way when you basically have limited (or no) other obligations besides training. That would include working up to 20 hours per week.

It is not near as hard to train 100+ miles a week when you have all day to do it. And of course get the benefit of the extra miles.

Right. So Mark Nenow still runs 27:20 all the way back in 1986 off of 60 mpw, yes? This is comical. It took YEARS of Nenow running 140-150 mpw to get to that level. Because one thing higher mileage definitely does is improve running economy over time.

It’s not for everyone, but I suspect the people who say they can’t ever get to higher volume never took enough time to build there or ran everything too fast. After all, 100 mpw, as high as that sounds, is really only a 4/10 double each and every day (maybe a 16-miler on the weekend). But most young people, given the time and patience and careful build can get to a 4/10 double every day like a metronome.

You're simply wrong. I have consistently run 150mpw and not go sub 2.30

No one really knows. It just works. Notice how no one can really answer your question? It's something that just works.

Why does Steph Curry shoot 3's in practice?

Common Sense