You mean everyone doesn't do this?

A friend of mine emailed me this question the other day, and when I got done with my reply, I had written far more than I intended.  I know it's a topic that has been tossed around in various forms time and time again, but I figured I'd put it out there for others to mull over.
 

To be sure, and I can't emphasize this enough, 85-90% of running aptitude and success is up to the runner and can be affected by your aforementioned habits of training, dedication, consistency, etc.  It's that 10-15% that makes amazing running feats possible and separates the Olympians of today from the rest of us.  I fully believe that, if I trained like Galen Rupp, I could push my 5k down from my current PR (16:36) to around 14:30-15:00, maybe even faster; I just don't know.  However, I fully believe that just the right ratio of dimensions of legs and body, just the right functionality of lungs, just the right muscular response to training and baseline vascularity (all genetic predispositions that cannot be altered through training), coupled with just the right environment growing up, like, say, spending the first 18 years of life living at 7000 feet (environmental factor out of runner's control), that amazing things are possible.  With an influx of interest, money, and attention to running (like what Rupp, Ritz, Webb, etc. have gotten), then such phenoms that have all the right puzzle pieces will be found.  Also, when an aptitude is seen as a way out of poverty and desolation, such as what the Kenyans have found, incentive will be present as well.  They've all got just a tiny percentage better functionality in a very small subset of their anatomy and physiology, that, when multiplied by 1000 steps or 1000 heartbeats or 1000 breaths can actually add up to something.
 

That said, I think that the farther you go, the more training takes precedent over "talent."  An aptitude to be in the Olympic 100m dash is determined at birth, and the rest of us just have to suck it.  I'll never be able to do what Usain Bolt does, and I couldn't even come close, regardless of how much I tried.  On the other hand, I fully believe I could be in the same ballpark and competitive with, say, Anton, if I were willing to put in the work he has.  I'm not, and most people aren't.  Obviously, Bolt and Anton are the extreme ends of the spectrum, and I think there is a full continuum of training vs talent in between, but I really think that the vast, vast majority of it all is training.
 

As some anecdotal evidence, I weighed the same at age 11 as I did at age 20 (a rather substantial height difference, though).  For being over 6 feet tall, I've got relatively short legs, and I'll never be as lean as the Kenyans.  I started as the slowest person on my XC team (like, girls and all) and have finished DFL more than once.  My freshman year, my 5k's started around 27 minutes (which was much faster than when I was in middle school, when I was thrilled beyond measure to hit a 28:xx, and the slowest 5k I remember being a 45 as a kid).  I would have been a prime candidate to play the "no talent" card and give up.  With this as a background, it almost personally offends me when people claim no talent, and it DOES personally offend me when most people tell me that they would love to do the running I do, but that I'm clearly far more talented than they are, so they're not going to beat me; I've put in too much work to attribute this to a simple natural gift.  I worked my butt off over the rest of high school to end up with a high school PR of 16:57 and be on the still-standing school record 4x800m team, then keep on going to do this ultra nonsense.  I understand that a 400-pounder is probably not going to beat me in a 5k, but a large part of this is due to previous choices that have lead to the current condition, as well as the mental state that is generally present in such instances.  I understand that some people have huge frames and don't respond as well to training, but this discrepancy in purely natural aptitude gets smaller as the distances get larger.  As a point of note, I should probably state the fact that I'm NOT a fast ultrarunner; based on relative results, I'm a far better 5k-er and 10k-er than ultrarunner; the simple fact that I've finished certain events and distances (read: been willing to complete) makes some people *think* I'm a good ultrarunner.

 Talent in the (distance) running world is USUALLY used the same way that luck is used in the rest of life.  A copout.  People don't want to recognize that they can do these things, run these times, cover these distances, accomplish these cool feats, because once they recognize the capability, it's entirely on them.  They can't blame it on talent or parents or luck.  They have to own up that they aren't willing to put in the work.  I take full responsibility for not being like Anton or Meltzer or Roes.  I think most people would rather blame their knees.
 

All that said, running, like you said, is a simple act.  One foot in front of the other; how bad could it be?  The paradox is part of the beauty of the challenge.  It's something so simple, but so difficult.