The Marathon Wall – What it is and How to Beat It

By Rick Morris

It’s funny how some past experiences stick in your memory like super glue. Even though it took place many years ago, I still remember my first marathon. I was young, cocky and thought I could defeat anyone and anything, including the marathon. I had a bit of success with shorter 5K and 10K race and was ready for my next challenge. I chose the marathon since it was the “classic” distance running race at the time. I trained hard and felt highly confident that marathon success would come easy.

On race day I started out fast and got into a nice strong rhythm in the middle miles – faster than the pace I trained for, but I knew I could hold the pace. I felt so good at 15 miles I increased my pace even further above my planned pace. I was certain that no marathon wall could possibly block my way to a successful finish. If the wall had the audacity to drop down in front of me I would just break through it or climb over it.  At about mile 17 I started to feel a rather ominous tingling in my legs that was unlike anything I had every felt in shorter races. But, I wasn’t too concerned; I still had my confidence and will power.

At mile 20 that tingling turned into a near numbness and my confidence began to wane. When I struggled past the 22 mile marker the numbness has morphed into something akin to running with bags of red hot lead balls filling my leg muscles that left me praying for a return of the near numbness of mile 20. By mile 24 my mind had deteriorated as much as my muscles and I my will to continue jumped the sinking ship. I had been reduced to a bumbling shell of a runner with the mind of a zombie. Thoughts of breaking through the wall had been replaced by a strong desire to sit down right where I was and not move.

After stumbling across the finish line 2.2 miles later with a numb mind, zero energy and non existent muscle power, I swore I would never again run a marathon. Then something remarkable happened. The wonderful volunteers at the finish line handed me a large chocolate chip muffin. Not exactly a gourmet meal, but at the time it looked like ambrosia. I scarfed down the muffin and the flood of simple carbohydrates combined with my supine position on the ground immediately made me feel better and I started planning my next marathon, promising myself that from that point on I would give the marathon the respect it deserves.

That was my first encounter with the marathon wall. The wall is a somewhat intimidating term that is commonly used to describe the devastating feelings of fatigue and sometimes confusion that can occur in the final miles of a marathon. The wall is hard to describe to a non runners. It’s something that you need to experience to really understand. Jerome Drayton, winner of the 81st Boston Marathon, said it best: “To describe the agony of a marathon to someone who’s never run it is like trying to explain color to someone who was born blind.”

While the wall and the marathon distance are joined at the hip, that doesn’t mean it can’t be avoided or overcome. With proper training, intelligent race management and proper mental strategies you can avoid the marathon wall or at least minimize its impact on your race.

Brains and Brawn

Overcoming the marathon wall starts with an understanding of what causes it. Researchers have identified two primary causes of running fatigue – central and peripheral or more simply “brains and brawn”. Peripheral fatigue (brawn) is caused by chemical and physiological factors in your exercising muscles while central fatigue (brains) is associated with the efforts of your central nervous system (CNS) to maintain a homeostasis or “balance” of those chemical and physiological factors and prevent damage to your muscles.

Causes of peripheral fatigue include hydrogen ion build up, accumulation of extra cellular potassium, muscle damage and hypoglycemia. Hydrogen ion and potassium accumulation usually only occur at faster 5K and 10K race paces and are not typically a cause of marathon running fatigue. The main peripheral causes of marathon running fatigue and hitting the wall are muscle damage and hypoglycemia.

The energy to power your muscles come from adenosine triphosphate (ATP), which is formed from the metabolism of fats and carbohydrates. Your body prefers to use carbohydrates which are stored as glucose in your blood and glycogen in your muscles and liver. Unfortunately your stores of glycogen are limited. Most runners are able to store somewhere around 2000 to 2200 calories worth of glycogen in their liver and muscles, which is enough to energize about 20 miles of running. When you run out of glycogen your body is forced to rely almost completely upon fat metabolism to supply energy.

Fat supplies more energy per gram than carbohydrates, but your body is much less efficient at converting that fat to energy, so you begin to slow down and suffer from fatigue. So as you can see, it’s no accident that many marathon runners hit the wall at around 20 miles. That’s when they run out of glycogen and they become hypoglycemic.

The initial effects of hitting the marathon wall and hypoglycemia are physical in nature. Your muscles fatigue and your pace slows. Your brain runs on glycogen just as your muscles do. Your brain takes priority over your muscles, so when you run low on glycogen, your brain will take what’s left and your muscles much fend for themselves. As your glycogen levels plummet even lower your brain begins to suffer from the effects of hypoglycemia and the wall. As a result your brain starts to feel like it’s in a fog. You become confused, your will power drops and you may become very emotional. I have seen grown men crying like a baby in the final miles of a marathon.

For many years peripheral fatigue was given the lion’s share of the blame for marathon fatigue and hitting the wall. Now, many researchers, led by Dr. Timothy Noakes, believe that central fatigue plays the largest role in hitting the wall. The theory behind central fatigue is that your CNS is making an effort to protect your muscles, your body and also maintain a chemical balance in your body. If it were up to us as runners we would run as hard as we could until we dropped from physical exhaustion. Our will to keep running would drive our muscles to their very limits. We would run until our damaged muscles and chemically out of whack physiology finally breaks down and collapses.

That kind of catastrophic breakdown is not a healthy situation and it’s one that our CNS tries to prevent. Your heart and brain must have a source of glycogen to keep operating. When your CNS senses that you are becoming hypoglycemic or that you are pushing your muscles to the point of damage, it begins to cut off signals to your muscles. It forces you to slow down to protect your muscles, brain and heart. You sense this through feelings of fatigue. Your CNS is dropping the marathon wall down to keep you from reaching those catastrophic levels of chemical imbalance, hypoglycemia and muscle damage.

It is also believed that your CNS not only senses physiological changes in your body, but it can also anticipate upcoming requirements and manage the signals to your muscle accordingly. For example, before a marathon your CNS calculates how much energy you will need to complete the race and “doles out” signals to your muscles at a pace that will allow you to finish without catastrophic system failures. In a sense, your CNS is setting your pace.

Avoiding the Wall

It seems like the best marathon strategy would be to avoid hitting the wall. But, do you really want to do that? That may seem like a silly question on the surface. Of course you want to avoid the wall, who wants to go through that? If you are a new marathon runner or only want to comfortably finish the race, you should try to avoid the wall. And that is something you can do with proper training and race management. But if you are racing the marathon or running for a PR then you want to push yourself to the fastest pace you can manage. Racing a marathon is a game. It’s a contest between you and fatigue. In order to run your fastest possible pace you don’t necessarily want to avoid the wall, but you want to delay its debilitating effects until 26 miles. If you finish your race with relative comfort you could have run harder. If the wall blocks your way before the last mile or so, you probably pushed a bit too hard.

Whether you want to avoid the wall completely or delay its effects until the finish line you can do that will proper training, race management and nutrition. Your weekly long run is the best training for avoiding the wall. The progressive long runs will condition your muscles for the marathon distance. It will build your endurance and help make your muscles more injury resistant. If you are racing the marathon or trying for a specific finishing time, it’s critical to include some goal pace long runs in your training. That will make your body more efficient at running at your goal marathon pace and will push back the effects of the marathon wall.

Marathon race management can sometimes be challenging. You feel so strong early in the race you tend to run too fast. That is the biggest and most common marathon racing mistake. If you run faster than you should early in the race you will burn glycogen and too fast a pace and will pay the price by hitting the wall later in your marathon. Make sure you stick to your planned pace early in the race and conserve those valuable carbohydrates for the later miles.

Another part of race management is the mental strategies you use during the race. There are a number of associative and dissociative techniques you can use. Associative techniques are when you pay close attention to and focus on how your body is feeling, your stride, course conditions and your competitors. Dissociative strategies involve mentally distancing yourself from your fatigue and the race. Instead you visualize yourself in another situation or on some other object. For example, instead of focusing on the race and your fatigue you may visualize yourself on the beach of a desert island or you might place all of your focus on some point on the horizon. Most studies have shown that experienced, competitive runners perform better using associative strategies while new runners may do better using a dissociative technique. See association and disassociation for a more in depth discussion.

Marathon running and low carbohydrate diets get along like water and oil. They just don’t mix. You should be following a high complex carbohydrate diet throughout your training and be especially careful to consume a large amount of carbohydrates in the last few days before your race. See marathon nutrition for more information

Breaking Through The Wall

OK – You carefully followed your training program, you kept your pace down in the early miles and you consumed a high carbohydrate diet, but you still hit the wall. What do you do now? Can your break through the wall? I don’t think you can. I know you have probably heard stories of runners breaking through the all and experiencing a Zen like runners high. I like to keep an open mind, so that may be possible, but in my experience, once you hit the wall your body has reached a mental and physiological condition that is difficult to recover from while running. That being said there are still some actions you can take to get you through the wall and to the finish line.

One way to get past the wall that may seem crazy at first glance is to speed up. I know, you think I’m out of my mind. How can you speed up when you’re hurting so badly? Well, there is a physiological reason that it works. You have probably been running a fairly even pace through your marathon. That means you’ve been using the same muscle fibers. Those muscle fibers have used up all of their glycogen and have become exhausted. But there may be some other muscle fibers that have not become exhausted – your fast twitch fibers. Your fast twitch muscle fibers have not been used extensively during your moderate marathon pace. Increasing your pace will activate some of those fast twitch muscle fibers that still have some remaining glycogen. It won’t be a lot, but it could be enough to get you through those last couple of miles.

Another wall breaking strategy involves playing a trick on your CNS. Remember that your CNS is cutting off signals to your muscles to prevent any catastrophic system fatigue. That’s one of the causes of the marathon wall and fatigue. While your CNS is very powerful you are able to override it for short periods of time. It’s sort of like an emergency power system. You’ve probably read stories of people that perform remarkable feats during emergencies. For example I recently read about an 80 year old man whose grandson was trapped when a car fell off a jack. The man was able to lift the car high enough for his grandson to escape. Under normal circumstances, the man’s CNS would not have allowed that because of the extreme muscle damage it would cause, but he was able to override his CNS because of the emergency situation.

Athletes often do that same thing. Football players may psych themselves up by hitting each other on the helmet, banging bodies or smashing each others shoulder pads. A competitive weight lifter might work themselves up to a mental and physical frenzy before attempting a heavy lift. You can do the same thing as a marathon runner that has hit the wall. You need to find someway to psych yourself up. Imagine a charging rhino chasing you. Pick a competitor in front of you and pass them at any cost. Get mad. Get angry. Get desperate. Do what ever you need to do in order to break the hold your CNS has on you. This takes some practice but eventually you will be able to call on your “game face” at will and override your CNS. Again, it will only last for short time before your CNS regains its hold, but it could give you the extra mile or so you need to defeat the wall.