How To Avoid Hitting The Wall On Your Marathon: 6 Expert Tips

Running a marathon is HARD, but what makes it even harder is “hitting the wall.” If you’ve run a marathon, there’s a good chance you know what it means to hit the wall, because it’s an unmistakably terrible feeling. 

Hitting the wall happens in a marathon is when your body has run out of fuel and to conserve energy, forces you to run slower. Your legs feel like bricks and it takes every ounce of effort to move them and keep heading towards the finish line. 

Hitting the wall, also called “bonking”, is a common marathon experience that unfortunately, has caused thousands, if not millions, of runners to miss their PRs and even drop out of races. 

But the good news is, you can avoid hitting the wall with proper training, fueling, and race pacing

In this article, we will cover:

  • What exactly does “hitting the wall” in a marathon mean? 
  • What causes hitting the wall?
  • When do runners typically hit the wall?
  • What does hitting the wall in a marathon feel like?
  • What to do if you hit the wall
  • Is it possible to avoid hitting the wall?
  • 6 expert tips to avoid hitting the wall

So, let’s go!

A runner sitting down on a low bench after most likely hitting the wall while running.

What exactly does “hitting the wall” in a marathon mean? 

Hitting the wall usually happens in an endurance event that takes longer than two hours. It is when your body doesn’t have access to easily-processed fuel so it starts to conserve energy by slowing you down. The athlete will feel sudden fatigue, making it hard to run.

What causes hitting the wall?

A person hits the wall when their glycogen stores (which are used as fuel) are depleted in the liver and muscles.

The body switches to burning fat which is a lot harder to access. Because the body can’t get energy from fat quickly, it is forced to slow down, and energy is used to try to tap into the fat stores.

Two runners hunched over with their hands on their knees looking tired.

When do runners typically hit the wall?

Runners usually hit the wall around mile 18 or 20 in a marathon, depending on how fast they are running. Glycogen stores last about two hours or up to 2,000 calories. On average, we burn about 100 calories per mile, depending on our pace and weight. 

Very slow runners may not hit the wall because their bodies will be able to use more fat as fuel, allowing for their glycogen stores to last longer. 

What does hitting the wall in a marathon feel like?

Hitting the wall in a marathon is a physical and mental assault. You are hit with sudden fatigue in which it is difficult to move your legs, almost like you are trying to move them through quicksand. 

You also experience very negative feelings with a voice telling you repeatedly that you can’t keep going and should quit. 

This is all by design. When you’re almost out of glycogen, your brain begins to panic and believes it needs to preserve itself. Therefore, it increases the production of serotonin which can inhibit control of your muscle fibers and signal serious fatigue which leads to negative thoughts telling you to quit. 

Related: What’s a good marathon time?

A woman hunched over on the side of the road, most likely after hitting the wall.

What to do if you hit the wall

You can push through the wall in a marathon, and it won’t hurt you. When you hit the wall you should:

  • Find one positive thing and focus on it. It could be that your fingers feel good if everything else feels bad!
  • Find someone to run with and talk to them to distract yourself from the pain. 
  • Focus on putting one foot in front of the other to keep moving forward. Forget about pace. 
  • Repeat a mantra that keeps you motivated like “I am strong,” or “I am a warrior.”
  • Think of things other than running like the crowds or your grocery list. Studies show disassociating thoughts can help recreational runners push through the wall. 

Related: Average Marathon Finish Times

A group of marathoner runners looking tired.

Is it possible to avoid hitting the wall?

Yes! It is possible to avoid hitting the wall. The solution lies in proper fueling, training, and pacing. Here’s how:

6 expert tips to avoid hitting the wall

#1: Do a long run every week. 

The only way to prepare for running for a long time is to run for a long time–repeatedly. Every week of your training, you should be doing a long run.

By running long, your body learns how to store and process glycogen more adequately. By increasing your glycogen stores, you can maintain a pace and delay fatigue. You will also build mental strength, teaching your brain you can go the distance! 

Here are some general rules of thumb for your long run:

  • Your long run should be about 30-35 percent of your weekly mileage (more for low mileage runners). So, if you are running 30 miles per week, your long run would be about 9 miles per week. 
  • Increase your long run week over week by 1-2 miles.
  • Do not increase total weekly mileage by more than 10 percent week over week, unless prescribed by a running coach. 
  • Do most of your long run miles at an easy conversational pace, to teach your body how to tap into its energy sources including glycogen and fat.
  • If you are going for a goal race time, run some of your long runs at your goal marathon pace in the form of a tempo, fast finish, or fartlek, to get the body used to running at that speed.

Related: Hitting the Wall: A Survival Guide

A group of marathoner runners filling the street.

#2: Do at least one really long run in your training. 

About two to three weeks out from your marathon, you should do a run long enough to prepare your body to run your marathon—but not too long that you can’t recover in time for the race. 

This really long run prepares your body and mind to go that distance. How long your long run should be, depends on your estimated marathon finish time. 

Here are estimated durations according to running coach Laura Norris and renowned running coach Greg McMillan of what your longest long run should be based on estimated finish times:

  • If your marathon finish time is below 3 hours, then you will likely do 1-3 long runs of about 3 hours, or no longer than your estimated finish time.
  • If your marathon finish time is below 4 hours, you will likely run 1-3 long runs of 3:30, (over 20 miles), and (again) no longer than your estimated finish time.  
  • If your marathon finish time is above 4 hours, you will cap your long runs at about 3:30 hours.
  • If your marathon finish time is about 5 hours, you will cap your long runs to 4 hours. 

Related: How long should your longest long run be?

A runner opening an energy gel.

#3: Train your gut. 

A lot of marathoners bonk in their marathon because they didn’t practice fueling during their long runs. This is a huge mistake. Your gut, like any muscle, can be trained. 

To train your gut, you need to take in gels during your long runs to teach it how to break down fuel with less blood flow (because the blood is flowing to your extremities). Many runners won’t take fuel or perhaps worse, try it on race day, only to get GI distress because your body can’t tolerate the carbohydrates while running. 

So, practice your fueling by aiming for a gel (or 30 grams of carbs) every half hour with water. By giving your body glycogen to use while your run, you will preserve your glycogen stores and delay or AVOID hitting the wall altogether!

Related: 18 Whole Food Alternatives to Gels

A collection of food with a sign that reads carbohydrates in the center.

#4: Carb load for days ahead of the race.

Carb-loading isn’t the pasta dinner the night before. That doesn’t give your body enough time to process and store the carbs needed for the race. Carb-loading happens in the days leading up to the race. 

  • About three days out start eating 80 to 90 percent more carbs per meal, says registered dietician Kristy Baumann
  • Drink at least 80 ounces of electrolytes and water throughout the day, too. 
  • Eat a high-carb breakfast the morning of the race and then a snack of some crackers or half a plain bagel about an hour before. 
  • You can also take a gel at the start line. 

This will stock your glycogen stores, so your body has more fuel readily available to it as you run.

Related: How to Carb Load

Four bottles of colorful electrolyte sports drinks.

#5: Fuel early and often in the race.

Studies show that those who start fueling early in their marathons have better marathon finish times. So, don’t wait until you start feeling bad to take in fuel (which can be chews, gels, candy, sports drinks, or real food). Start taking them every half hour. 

  • Take a gel (or preferred fuel) at the start line with water. 
  • Drink electrolyte drinks in between gels. 
  • Take a gel or fuel every 30 minutes of your marathon with water.
  • Don’t skip taking fuel or water, even if you feel like you don’t need it. 

You will ideally learn which gels or carb sources you tolerate best by practicing your fueling on your long runs!

#6: Pace yourself!

The faster you run, the more fuel you burn through. And the faster you run at the start, the less energy you will have for the rest of the race. Remember the old saying, “it’s a marathon, not a sprint. So, don’t make the rookie runner mistake of going out too fast. Pace yourself!

It is easy to get caught up in the excitement of the crowds or get pulled into someone else’s pace, deluding yourself that maybe you’re fitter than you realized. That is a huge mistake. 

Stick to your race plan or the pace you trained for. Run at an easy effort. In the last remaining miles, assuming you’ve taken our advice and avoided hitting the wall, you can give it all you got! 

If you need help training for a marathon, check out our marathon training resources!

A group of three women running a marathon.
Whitney Heins
Whitney Heins is the founder of The Mother Runners and a VDOT-O2 certified running coach. She lives in Knoxville, TN with her two crazy, beautiful kids, pups, and husband. She is currently training to qualify for the 2024 US Olympic Trials marathon.

3 thoughts on “How To Avoid Hitting The Wall On Your Marathon: 6 Expert Tips”

Leave a Comment

This site uses Akismet to reduce spam. Learn how your comment data is processed.