HubyJugy wrote:
Worst case scenario: Let’s say someone (who is in shape) has no running talent. No talent as in a very low natural vo2 max, low lactate threshold and poor speed. Also, poor trainablity/adaptability to training.But let’s say they are very motivated and very durable so they don’t get injured, what times could they run (800, 1600, 3200, 5k, etc) with 4 years of consistent, smart and hard training?
In my opinion, someone with no talent who works hard can get down to 4:40 maybe 4:30 for the mile and 16:20ish for the 3 mile.
I think you are massively over-rating what "no talent" would translate to. I wasn't a superstar, but was able to win my area x-country, and to run for the county (English equivalent of state) as a high-schooler. That was with less than optimal training. In my teens, I would be in the top third in a national x-country championship.
So, I'm going to suggest that although light-years from elite, I had a pretty reasonably degree of natural talent - at that stage pretty undeveloped. I carried on for training and racing from then until now. I wasn't a high-mileage runner, but did train with a running club (in England until I moved to the US in my late 30s) and trained regularly and hard, with plenty of opportunity for competition.
With that, I got down to 4:20 for a mile - either side I was 1:57.5 for 800m and 8:45 for 3000m - so that was about right.
My point is, if I was lucky enough to be a reasonable high-school runner and win area races in a pretty much untrained state, and ended up with a 4:20 mile, the I think that 4:30 for some one with all those negatives you mention is going to be totally impossible. The "no speed" alone is going to rule them out of the kind of 400/800m speed needed to run a 4:30 mile. That's especially so, as you've said that they have poor adaptability to training, so the four years of consistent, smart and hard training isn't going to improve them, so they are stuck with the basic speed.
Within most of your limitations, the best chance of respectability would a guy who had a ton of slow twitch going long.
I think that your original guy is going to be lucky to break 6 minutes for a mile, which I think is still quicker than asked for in fitness tests for police or most military.