anything over a 40 yd/ 60m/ 100m type distance is work. sheer speed might win you a short sprint. because you have to tap into less aerobic/metabolic resources, it matters less what you eat, etc. but you could be built the right way and if you get a late start it will take you a year or 2 at events of any meaningful distance to catch up to the pack and your possibilities. and even then you look at the elite and they at one point do x time and at y time drop 3 seconds. did they mature more or was it work?
i do feel like body build/ lungs/ heart/metabolics matter. i often felt like my muscular calves were an issue running XC type distances that i never noticed at my usual <800/hurdles runs.
i think there are natural builds you will see xerox machined at DL type meets for, say, the 800m. but i resist it a little as i felt like i got run off from hurdles -- despite being our best 300H guy (and i'm talking around 40 as a HS soph) -- because i was so short i was horrific doing the usual drills and perceived as not trying. but i see short japanese guys who are solid at the 110H.
so how much of it is nature and how much of it is that normally a short 800m guy like brandon miller gets shifted someplace else because he doesn't fit the prototype.
but anyhow, my basic point was you could take a fit soccer player off the street and while they'd be solid at 800m or a mile my guess is they couldn't break 2 mins off the street. ditto you go grab some half-fit guy with the right build to be a stereotype 800 runner, off the street, and have them do a time trial. they might have more theoretical upside but they would lose to the worker week 1. because past elementary school or so, and past about 100m, everyone starts being so good and so hard working you cannot do it on raw talent alone. now, in theory, 50 yard foot race, i think a naturally gifted guy could win it, even with a beer belly, but only if they didn't pull a hammy. which itself hints at work still matters. just less.