What is the cause of "marathon wall"

If you don't have a border, you don't have a country -DJT

Oh, different wall.

My experience and a little reading tells me that this is mostly a duration-based phenomena; it is something that slower runners - like myself - have to deal with that faster runners don't. Let's say it takes an average of 2:30 to burn thru your glycogen stores. That basically means that - on average - a 2:15 runner can run a marathon mostly on carbs, while a 2:45 must be prepared to either ingest carbs - and be working at a low enough intensity to DIgest them as well - or use some alternative fueling method, ie Maffetone...

Of course, pro runner don't meet the wall...

But for all the others who are above 2:30 , it is a phenomenon that can happen and will happen sometime. The longer the race is, most chance there is to happen.

But what to do to prevent it? I heard some people saying it is really specific to marathon and happen very rarely in ultra trail events. Is it due to higher pace in marathon, it is due to running on concrete and damaging your muscles, sending alarms signals to the body?

The main issue is depleting muscle glycogen and switching to burning fat, which is a less efficient fuel.

If you run the right pace and have trained properly, the transition is manageable. The last 10k feels like you are running all out, but you can hold your pace and finish strong. I think this is correctly named the "wall".

If you are not properly trained or run too fast (or both), you will not hit the wall. You will bonk. You have depleted your muscle glycogen too rapidly and can only muster a jog well off your pace for the last 6-8 miles (or worse).

It is different for everyone, but for me, I was best able to get through the wall when I was running a lot of marathon paced miles in my build up. Fast long runs, very long intervals (4x3k; 3X4k; etc.) and big tempos (10mi mp) all seemed to get me ready to run that last 10k all out.

Fueling never seemed to make a difference for me. I ran a smaller marathon that was a two loop course. They ran out of gatorade on the second lap and I had no GU. I ran the last 13 mi on water and still ran within 1 min of my lifetime PR.

Most of the time it's because they just went out too hard, and the last 25% of the race is when that is most evident. Just like a mile, if someone who thinks they're fit but isn't runs really fast the first part of the race they will probably make it past halfway just fine, but that last quarter of the race they're pulling an anchor. Fueling can definitely be part of it, but usually people are just running faster than they're actually capable of.

So that's the consensus?

Going to hard is going to make you deplete you completely? I am not talking about dropping a little pace and finishing weak, not being able to maintain the programmed pace, but falling hard to recovery pace, to absolute jog, just to be able to cross the line.

I heard some people saying that it happen mainly in marathon and rarely in longer race. Because of pace? Because of the surface? Because of the training?

Long race are a must for marathon, however, you don't often run these long race ar marathon pace for more than 30 km, and generally that wall hit in the last 10k.

As I, the great Canova once say:

There is no such thing as the wall - only a runner underprepared for the race they are trying to run.

So lack of training? But preparation is such a wild guess and estimate. You can felle prepared and crash out miserably.

Evolution! In the old days of persistence hunting, the successful hunters who caught the prey within 20 miles got back to the cave first and claimed the women. Hunters who could run farther than that could maybe catch a few more kinds of animals, but they got back to the cave much later and the women were unimpressed. So the ability to run more than 20 miles was weeded out of the gene pool.

That's why even today, being able to run a marathon makes you less attractive to women. Men who can should not admit it.

Ermin Ngamet wrote:

Of course, pro runner don't meet the wall...

Sure they do, it happens all the time. You can burn through your glycogen stores in under 2 hours if you run fast enough (and therefore burn glycogen at a high enough rate).

Some facts:

- Caloric requirement of racing 42km is practically independent of the speed. Elites spend similar amount of calories (but at much faster rate).

- If you're racing optimally, you're running roughly at your aerobic threshold, and mostly on glycogen with significant percent of fat. If you're racing faster than optimal, you can either hit the wall (deplete glycogen too fast because you burn higher percentage of it) or you bonk (accumulate too much acidity in your muscles). Elites usually bonk, not hit the wall.

- You hit the wall because your glycogen stores are low (but not empty) and your brain tries to conserve them. You can teach your body to use higher percent of fat, to store more fat inside your muscles and also teach your brain to trigger that fatigue a bit later. Long run and high mileage are the two tools for that.

- You can store more glycogen via carbs loading and you can additionally take about 60-90 g/hour of carbs. This makes it possible to move the wall further than 42km. Your last 5-10k will still be very hard and require mental toughness to not slow down, because of many different types of fatigue that accumulate by that time.

Bad Wigins wrote:

Evolution! In the old days of persistence hunting, the successful hunters who caught the prey within 20 miles got back to the cave first and claimed the women. Hunters who could run farther than that could maybe catch a few more kinds of animals, but they got back to the cave much later and the women were unimpressed. So the ability to run more than 20 miles was weeded out of the gene pool.

That's why even today, being able to run a marathon makes you less attractive to women. Men who can should not admit it.

Why do you even exist?

Thanks for the detailed answer.

That message sent by the body about low glycogen level, the best way to get around is refueling? How fast the added fuel is ready to be absorbed and used?

I am not talking about the pain which invade the muscle, but the feeling of complete lack of any remaining energy. Running on fat can't achieve anything good.

4353 wrote:

[quote]Bad Wigins wrote:

Why do you even exist?

Because this place is a safe space for idiots with empty lives. Here they can don their troll monikers and feel that for once in their awful lives they are someone. And with their identity they come here daily and proudly vomit their stupidity onto these boards feeling like they belong.

4353 wrote:

Bad Wigins wrote:

Evolution! In the old days of persistence hunting, the successful hunters who caught the prey within 20 miles got back to the cave first and claimed the women. Hunters who could run farther than that could maybe catch a few more kinds of animals, but they got back to the cave much later and the women were unimpressed. So the ability to run more than 20 miles was weeded out of the gene pool.

That's why even today, being able to run a marathon makes you less attractive to women. Men who can should not admit it.

Why do you even exist?

Because my ancestors caught the prey within 20 miles and claimed all the women.

You probably have those throwback marathon genes, if so the question is HOW do you exist. You should be extinct.

theJeff wrote:

My experience and a little reading tells me that this is mostly a duration-based phenomena; it is something that slower runners - like myself - have to deal with that faster runners don't. Let's say it takes an average of 2:30 to burn thru your glycogen stores. That basically means that - on average - a 2:15 runner can run a marathon mostly on carbs, while a 2:45 must be prepared to either ingest carbs - and be working at a low enough intensity to DIgest them as well - or use some alternative fueling method, ie Maffetone...

Wow...The reason elites don't tend to hit the wall is that they are way more economical runners (a necessity to run 2:15 and below), their skeletal muscle to total body weight ratio is high, therefore they have enough storage capability to have the energy required per Kg of body weight for 42km. You can pretty much work out how much CO2 based on the O2 consumption (not the VO2 Max)

For me at 59Kg racing weight (53.5kg in PB years mid 20's, still heavier than a lot of elites), I could run a sub 3 age 58, sub 2:30 age 27 with enough fuel to not hit wall, not even gels

I say it's simply a lack of training/fitness and poor pacing, not too unlike in a 400m or 800m or any other race, except in agony duration.

The answer you're looking for is this: it's very difficult to race a distance that is more than 78% of your typical long run.

It's no different in other endurance sports. For instance, if you want to be able to really race at the end of a 4 hour bike race, it's going to help if you've done some 5+ hour rides. Same goes for running. If you're racing a half marathon with real aggression you probably will need to have been doing some 17+ milers.

Does that mean you need to be able to do a 33-34 mile long run to race a marathon with an almost reckless agression? Yes, it does. Knocking out 50-60K with some quality on trails is doable about 4 times every 3 months and it makes a huge difference if you take care of your nutrition. It allows you to truly race a marathon. Meaning you can surge, redline for a few miles and then recover quickly settling back into your marathon tempo.

If you only ever do 20 milers you're going beyond what your body has been accustomed to and it will shut down to protect itself, thankfully, otherwise us junkies would destroy our bodies much faster than we do.

mwh wrote:

I say it's simply a lack of training/fitness and poor pacing, not too unlike in a 400m or 800m or any other race, except in agony duration.

It's completely unlike a 400m or 800m race.

Ermin Ngamet wrote:

Thanks for the detailed answer.

That message sent by the body about low glycogen level, the best way to get around is refueling? How fast the added fuel is ready to be absorbed and used?

I am not talking about the pain which invade the muscle, but the feeling of complete lack of any remaining energy. Running on fat can't achieve anything good.

Best strategy is of course to prevent this. However, to get a boost in performance it's enough even to just have some carbs in mouth. See Tim Noakes' "Lore of running" for reference - there were studies done that washing your mouth with carbs drink vs placebo increases performance. To actually get the benefit of those carbs and not to trick the brain - you need about 1minute/gram, so don't wait for the wall, prevent it.