Is base fitness 100% genetic?

How much mpw do you run and what pace?

Island wrote:

How much mpw do you run and what pace?

Currently like 40-50 at 7:30-8:00 ish

everyone but Kipchoge etc might consider to sue his/her parents.

How old are you and when did you start running seriously?

Most high school runners can improve about a minute on their untrained fitness. I improved 2:01, from 6:40 to 4:39. My best friend did almost the same training for 4:16, but started at 5:45. Not many do 2:00 without a major growth/maturity spike (not the case for me, just lots of training.)

ummmmmm wrote:

How old are you and when did you start running seriously?

17, started running seriously at 15 so not very long

I think there's a lot of genetic component. I ran 5:30 in 6th grade pe mile and now I'm running xc/track d2, I also did train hard through HS.

Base fitness is largely genetic. As is how much you improve by training. Read David Epstein's book The Sports Gene for more info.

I think people confuse base fitness with genetic superiority regarding low body fat and form. Some people have a body that fits really well with distance running rather than some people who are awkwardly disproportionate like a long torso/short legs/ big bulky arms.

It's very difficult to determine "base fitness". Unless you actually lay in a bed for about 6 months you are always going to have some kind of fitness.

Don't worry about what your friend does. He might not be telling the whole truth. He might do other forms of physical exercise also.

The really important thing is how well you respond to training. Part of that is finding the kind of training you respond to best.