Can you run a solid marathon on aerobic running alone?

In theory you could run every run at just under LT1, maybe a touch slower than marathon pace to try and "push it up from below", like the NSA guys are doing with LT2. You might be able to accumulate more load than NSA too by doing this as you could make each run longer. I don't think anyone has tried it yet though.

Long runs recruit the type IIa fibers near the end even at the slower pace, and both type I and type II fibers are burning more fat towards the end of a long run, and there's at least 1 fat-burning enzyme to train. There's also the nebulous concepts of durability and muscle cramps. You probably want to do a 20-mile run 2 or 3 weeks prior to the race. Why not?

Sure it can be done.

85% easy and 15% marathon pace. I ran my first sub-3 at age 50 doing just this.

I was prioritizing mileage and since everything faster than MP gives me sore calves for several days, I did no speedwork at all.

In a hypothetical scenario where I did speedwork without getting injured, I would've run maybe 2 minutes faster, no more.

I think I misunderstood the original post as meaning no long runs. If we're talking about no speedwork, yes. But VO2 max training (time trials or sustained high HR with active recoveries) will increase stroke volume and mitochondria function. Just running 400's and standing around for 2 minutes in between is useless I think

I have sort of tried this, I went from vanilla to 95-98% of current MP, for basically all of my 3 workouts a week, but stretched the time to 45 and 50 and even 70 minutes, all broken up into between 6-15 min chunks. I did this from 16 weeks out. This was before sirpoc had laid out a marathon plan, around this time last year. I ran an OK marathon, it felt pretty rough at times in the build. You'll be surprised how much fatigue gets accumulated, past 35-40 minutes even at that relatively slower pace compared to vanilla.

Flip round to this year, another 8-9 months of vanilla getting faster, I then ran the more classic outline laid out, with the slow build up to the intense finish 2 weeks out. That felt hard, but I felt better in the race and i didn't really feel gradual fatigue build over weeks in the build. I preferred it, ran a much better marathon, for what that's worth. You could say there was some value in what I did as just ever increasing the base, but it certainly didn't feel sustainable with what I tried and I was pretty glad to see the back of it.

I keep meaning to post in the main thread or Reddit about this and perhaps it's time i did.

I’m doing this because of a work injury on a leg tendon… Lots of 5min KMs while is slowly heals.

Sure, assuming that you've done speed work and other training in the past, you could have a pretty solid marathon with that kind of build up. Will it be your max potential? No, but it wouldn't be far off.

However, continue that cycle for years and years and you'll gradually get slower, wondering what happened.

I mean, marathon pace isn't "easy." If you're going to run up to marathon pace, you're essentially allowing for LT1 training. That could leave you fit enough for a marathon, especially with decent mileage. Without faster running, your ceiling would be a bit limited, but what you described is the bulk of marathon training anyways.

I’ve got a buddy who does the overwhelming majority of his runs in the 6:30-7:30 pace range (maybe 1 Vo2 or tempo workout per month) and runs 2:30:00 give or take a few times a year. This guy was also the #1 runner on his XC team when they won their division of state though.

To me that’s not an indicator of how good of a training strategy nothing but easy miles is, it’s more an indicator that this guy could be running 2:15:00 +\- if he really wanted to.

How do you know that IIa fibers are recruited after a certain distance or time? O have heard/read this but where is the evidence that is actually happening?

Good question. Don't expect a reliable answer.

Patrick Martin ran 2:24 age 42 with almost just steady/easy running everyday and really high mileage with a lot of consistency. Said he started running only 3 years before.

I have a friend who doesn't come from an endurance sports background (he was always a good athlete but didn't compete in college) go 2:44 off of essentially 3 years of easy/steady running (literally no speedwork to speak of, even MP) averaging around 50 miles a week. I suspect he is genetically gifted though, and probably was born to do endurance sports.

I'm not bitter about it or anything.

I also have a buddy who used this approach after graduating from college. He'd run a respectable (for the time) 30:10 in the track, but he just really liked running. Bumped his mileage immediately to the 110 range and not to long thereafter placed 11th at San Diego RnR, 1 spot out of the money. He pushed his mileage further up and eventually started incorporating workouts, but rarely ran anything faster than M pace.

Biggest ever training block was 6 weeks at 210 mpw.

Ended up by taking 3rd at CIM (twice) and 15th in Boston (1st American)

Ran 2:36 (5:55 pace) in Chicago this year off of ~55mpw, LR up to 18 miles, with 98% of my mileage done at 6:20 for steadier efforts to 6:50 for easier.

My only workouts were 5k paced stuff with my high school team. Granted, I've got a 15:40 guy who worked me now and then in K repeats.

Essentially no sustained efforts at marathon pace, no tempos, no extensive mileage.

Undertrained? Probably. But I showed up healthy and happy and was satisfied with devoting the majority of my time and effort to my high school team which was enough to pull me to a decent time.

It can be done if you are willing to hurt

Yes, this is the type of schedule I had in mind.

I'm assuming other approaches didn't work out as well for you? Curious to hear about those vs this 85/15 approach.

Long runs definitely not excluded. Only talking about pace restrictions.

I ask the question because don't believe I've ever come across a marathon training plan that didn't involve some sort of speed work or at least threshold work.

Unexpected surprise to read the manu success stories here of those who have bucked the traditional ways. Makes you rethink the accepted wisdom.

Isn't half the battle of the marathon showing up to the finish line not beat up or worse injured? This might be a way to ensure you're more likely to get to the start in one piece.

And I wonder about the longevity too, getting stuck in a rut. Maybe doing a short bout of 5k training in the off-season would kick off the dust?

Short answer: yes, it can work — but with some trade-offs.