40 mpw marathon without real long run

2:35

Through half-way in 1:17 feeling great, massive blow-up and positive split, finish in 2:57.

I was never that good, but I ran a marathon three times on roughly that approach. It wasn't pretty.

It might work but it also might not work.
For Marathon you need endurance strength and that's why you need the long run. You might get away with fewer not so long runs but you need them. And your result will highly depend on them. The more long runs the better your results.

Just looking on a pace calculator and dream of the time he spits out will not work.

The most basic truth about success in running is that you can't cut corners. There are no shortcuts. If you don't do the work, you won't see the results. For marathons, doing the work means long runs.

If this was a successful approach, everyone would be doing it.

I ran a marathon on 40mpw, I was running 5k in 18:30 at the time. I had a lovely time through halfway, got a little uncomfortable between 13 and 18, then died a horrible death struggling over the line in 3:28. The worst thing to hear when you're completely spent is people in the crowd yelling "keep going! You can do it!" when you just can't. You can't will your way to getting more glycogen

One year when I was in grad school I was running 50ish mpw, not really training for anything, casually racing occasionally. I could run 29 minutes for 5 miles or 17-something for 5K. I did some 15 milers in training, no speedwork, and ran pretty hard most of the time. For some reason I decided to do a marathon on very short notice (less than two weeks, people are impulsive at that age). I was strong through 18 or 19 miles, hit 20 in 2:11 and finished in 3:01 with a nice 8ish pace for the last 10K after 6:30s up to that point. I think that's about what would happen to your guy.

I was a 9:01 3K guy in college and did pretty similar training for my first marathon one year out of college in 2012. Most of my "long runs" were 10-13 miles. I did maybe one 15 miler and one 16 miler. Weekly mileage was usually low 40s - I had one week where I touched 60 but that was the only time I was close to that. One tempo workout and a couple strides sessions per week.

Felt great clipping off 6:30-6:50 miles for 16 or 17 miles. Started getting tired around 18 then hit the wall pretty hard at 19. Those last 7 miles were a world of pain! Would not recommend. Finished just over 3:03.

You would think I would've learned my lesson, but I did pretty similar shenanigans in the subsequent 2 marathons I've run in my life. I've sworn off signing up for another one until AFTER I've completed multiple 70 mile weeks!

ON this training, you could complete a marathon, but you darn well better run a slow pace up to 18-20 miles. Aim for a negative split and it's do-able. The idea would be to actually pick up the pace from the 20-mile mark. Probably best to run with a pace group so as not to go to fast.
There is no substitute for long runs in marathon training.

the issue is he's not gonna be able to have enough energy through fat metabolism. now sign him up for a half marathon and he's good. I remember I did a really fast one ( for highschool) off of nothing longer than 4.5 mile daily avg and then one long run of like 9 miles

This is pretty much my old college roommate except we never raced 3k back then. His normal runs were 5-7 miles and his long run was 10. For marathons he'd extend that to 12. He always had a day off. Forty five miles was real high end mileage for him in a week. He dropped out of his first marathon and subsequent ones were all between 2:40 and 2:50. His best was 2:40 and a few seconds.

If the runner executed perfectly, ran at a fairly conservative pace, stayed adequately hydrated, and took the proper amount of fuel, it could be interesting to see how it would turn out. The runner is almost certainly going to hit the wall and work through a suffer fest, but it would be interesting to see how it'd turn out if all controllable facets of the run was executed well.

Too fast pace for a runner with that level. But with smarter method possible to run quite good Marathon. Geoff Smith ran a 2:09 debute and longest training run 10 miles.

If he's in 15:30 shape and is running solid effort 40 mpw, he can run a decent marathon just based off of fitness. But what does "decent" mean? I'd estimate somewhere in the 5:45-6 min per mile range, maybe a little faster if he's got years of training under him. He'd be hurting after about mile 18 though... you definitely need the long runs (18+) to strengthen your legs for the pounding. [Speaking from personal experience- I've been sub 2:22.]

I just ran Boston on 25-35 MPW.

The last 8 miles was slow and painful. I wouldn't recommend it.

I do some cross training too, but I just ran Boston yesterday, technically overweight (BMI 25+), on less than 50k/week and was 31st in my age group :)

my college team decided to run a marathon after our senior season. One teammate who had run a 31:50 10,000m and was logging 80-85 miles a week or so ran 2:33. The rest of us were in the 2:40's or worse. All of us had not run a marathon before.

That same teammate ended up running 2:22 about 5 years later. Another guy eventually ran 2:18 a few times.

The long runs/time on your legs are really important for the marathon.

the last 8-9 miles will be very rough if only doing 40 miles a week, but I ran 2:34 on 50 mpw, so it's possible. I still think the long runs are most important, even in a low-mileage scenario though.

Any decent college runner can complete a marathon by doing that kind of training, and if you are older I'm sure you can but it would be U G L Y.