Can anyone between ages 18-28 run sub 2:30 marathon after 5 years of training?

No.

If you hang around the finish line of a major marathon and watch the sub 2:30 finishers, go get breakfast and come back and watch people trying to finish under 4 hours, you will instantly know why it is impossible for anyone in their 20s to run a sub 2:30 marathon. You have to have a light frame to be able to run under 2:30. There may be a few outliers who carry a bit more muscle than others or are more big boned than others. But by and large the sub 2:30 runners are going to be 150 lbs or less and have a very light frame.

I am pretty sure you’re trolling, but I’ll bite just in case you’re not. Sub 2:30 is out of reach for probably 97+% of people. That’s 5:43 per mile for 26 miles straight. Only your good, college-caliber athletes are going to be able to do that. I went 8:26 and 14:46 in college and only managed a 2:34 (one attempt) off of very high mileage and consistent training. Your regular Joe, even with 5 years of hard training is going to be looking at more like 3:15–if they can even do the training and make it to the start line.

there are people who could train their entire lives and still wouldn't be able to run a single mile at that pace

This is an easy question. Doing everything right for years will allow you to possibly run a marathon that is "equivalent" to your best 5k. For 2:30, you need to be about at 15:30 runner. Few of those guys get there, though.

5k is a easier indicator of potential because it requires far less training to get within spitting distance of your likely ceiling. So ask yourself: how many people in their 20s can run 15:30?

8:26 is significantly better than 14:46. You seem like far more of a mid-distance runner.

Hell no. You are delusional. Most can't break 3:30 no matter how hard they train.

2:30 is already several standard deviations away from the mean.

?

No. I did it ( 8 years, not 5). But saw many others who had been running for longer that could not. some just have a different body structure. Ever seen those people with really big legs? Or those with big frames? Maybe some with those features did break 2:30, but I am certain that is not the norm.

therunnereclectic.com

Can Any ‘Normal’ Man Run a 2:30 Marathon?

Jon Waldron

“Any ‘Normal’ Man can break 2 hrs 30 min for a marathon!” “Really? Who would claim such ‘nonsense’ these days? This was the often-mentioned and often-proved claim made by New Zealand’s late, great …

Link:therunnereclectic.com/2015/01/02/can-a...

Lydiard thought the answer was yes but it is someone who is running 100 mile weeks for years.

14:46 equates to 8:29 per Daniels’ VDot. So 8:26 is almost exactly equivalent. Not sure where you’re getting your information or what your point is. 2:30 is far out of reach for most people.

You are an idiot. First off 2:30 is national class for woman. That’s 50% that is going to struggle. Then Go look at the body types of the bottom 25% of the population and ask if any of them are running 1 mile at 2:30 pace. Nobody is dumb enough to think anyone can run 2:30.

if you go the other way it is much harder. Can 1,5,10 or 25% of the population break 2:30 if they had 10 years and say a 10million dollar reward? We are left guessing. Few people train that hard cause the rewards aren’t worth it. Get every sub 4:50 HS miler to spend 5 years grinding out 70mpw+ and we would have a lot more sub 2:30 guys…

Anyone? Absolutely not.

Most runners will not survive 2:30 marathon training.

Can any teen score 1500 SAT after five years of studying?

Surely you’ve been to walmart

Or to the end of the backstretch.

Fine, I'll bite as well. This was essentially the goal I had, although it wasn't necessarily 2:30, but more what am I genetically capable of? After 8 years and plenty of high mileage on the edge of overtraining all too often, the best I could do is mid 2:30's. In hindsight I had a few limiting factors. First, body type, I'm 6'3", even with a slight frame that's not ideal. Secondly, I just didn't have natural cardiovascular ability. At my peak I had my vo2max tested at a university as part of a PhD students research project (meaning it was accurate) and it was 51. So my running economy was stellar, I just didn't have a capacity needed to be a sub 2:30 guy.

Trust me, I trained as best and hard as I could to get there. I was also fortunate to stay healthy and string together several training cycles that built on one another. I really had no excuses other than I just wasn't born to be a "fast" marathoner.