How to Avoid Hitting The Wall When Running

Most runners know the dreaded feeling. You start a long run or race with confidence, your stride feels smooth, and everything seems under control. Then, at some point, suddenly,  your feet seem to get heavier, and every step takes more effort. Your legs stop responding as they should, your pace drops sharply, and you suddenly feel exhausted. In the worst case scenario, your legs become like jelly and you fall to the floor, having no energy to lift yourself back up. If you haven’t seen this happen in-person, then watching the footage from the end of the London Marathon will show you a number of runners collapsing through lack of energy. This is what runners call hitting the wall. It is one of the toughest experiences in endurance running, but it is also one of the most preventable.

Hitting the wall happens when your muscles run out of accessible energy. It is a combination of depleted glycogen stores, rising fatigue, and a physiological stress response that makes your body feel heavy and unresponsive. While it is common, it is not a given. With the right fuel, training structure, pacing strategy, and race day preparation, you can avoid the wall entirely and run strong to the finish.

Today we’re discussing what causes the wall, how to fuel correctly, how to train your body to use energy more efficiently, and the small race day decisions that make a big difference. If you have ever struggled late in a long run or marathon, this is the explanation that will help you get past it.

First, a little more on the basics:

What Hitting The Wall Actually Means

To understand how to avoid the wall, it helps to know what is happening in your body. Running relies on two main fuel sources. These are carbohydrates stored as glycogen in your muscles and liver, and fat stored throughout your body. Glycogen is the easier and quicker fuel for your body to access. It supports faster running, hills, surges, and steady pacing. Fat is a much more abundant fuel source, but your body has to work harder to turn it into usable energy, which is why running on fat alone feels slow and heavy.

When you run long distances without topping up your carbohydrates, your glycogen levels drop. Once they fall too low, your body struggles to maintain pace. You feel tired, your legs lose their spring, and your brain starts sending warning signals. This is the classic wall. It is not a sudden event, even if it feels like one. It is simply the point where your body is switching from glycogen to mostly fat and doing it under stress.

Avoiding the wall is really about managing energy. You want to delay glycogen depletion for as long as possible by strategically boosting your carbohydrate levels during the run, teach your body to use fuel more efficiently, and reduce unnecessary energy losses. When you get all of these right and have also sufficiently trained your physical endurance, the wall never appears.

How Fuel Impacts Your Ability to Keep Running

Fuel is arguably the biggest factor in avoiding the wall. Even well trained runners will struggle late in a race if they under fuel, use the wrong type of fuel, or start their run already low on glycogen.

Here are the key parts of fuelling that matter most.

Eat Enough Carbs Before Long Runs and Races

Glycogen levels are highest when you eat sufficient carbohydrates. Your body stores glycogen in your muscles and liver and this is the energy you rely on from the first step. If you start a run with low glycogen, you are already closer to the wall.

Good pre-run or pre-race choices include rice, pasta, porridge, potatoes, fruit, and bagels. Many runners find that a high carb meal the night before and a smaller meal 2-3 hours before the run works well. Carb loading for even longer beforehand is another strategy commonly employed in preparation for a long run. The focus should be on simple, digestible carbs that top up glycogen without upsetting your stomach.

Use Energy Gels Strategically

Using energy gels is one of the easiest ways to avoid the wall during long runs and races. They replace the carbohydrates your body is burning through and keep your glycogen stores from dropping too low. As energy gels are simple fast-acting carbs that come in a jelly or fluid format, they work quickly while being easy to consume while running hard.

Most runners consume between 60g and 90g carbohydrates per hour, which is equivalent to 2-3 gels depending on the carb content. Some runners will tolerate more than this and others will find fewer carbs - such as 40g-50g per hour - work best. What matters most is experimenting with fuelling and choosing gels that are easy to digest, not filled with unhelpful additives or fillers, and taste good so you don’t put off taking them. Natural gels like Maple Ignite or Maple Coffee are ideal for this and are among the few energy gels on the market designed by real, everyday runners. They contain fast absorbing carbs that are gentle on the stomach and taste like real food because they are real food - maple syrup in fact! Choosing Maple Ignite and Maple Coffee gels makes it much easier to stick to your fuelling rhythm during those long runs.

If you are running for more than 90 minutes, you need carbohydrates while you run. There is no way around it. Without fuelling, you will burn through glycogen too quickly and hit the wall long before the finish.

Do Not Wait Until You Feel Tired

By the time you feel tired during a run, you’ve already missed the fuelling window. Your glycogen levels have already dropped and it will take time to get it back. Take gels BEFORE you think you need them and take them on a planned schedule, not based on how you feel. Your brain can tolerate low energy for longer than your muscles can, which is why the wall often feels sudden even though it’s not.

Think of fuelling as maintenance rather than repair. You top up way before you are empty.

Train Your Gut

Some runners hit the wall because they avoid gels entirely due to stomach issues. Gut training solves this. Practice taking gels at marathon pace during some of your long runs so that your digestive system adapts and becomes comfortable with fuelling on the move. It is a skill like any other.

Train Your Body to Use Energy Efficiently

Training plays a huge role in how your body uses fuel. Even good fuelling will not prevent the wall if your training structure makes it hard for your body to manage energy.

Build Long Runs Gradually

Nothing prepares your body for marathon or ultramarathon distance like consistent long runs. These runs improve fat oxidation, meaning your body becomes better at using fat as fuel at steady paces. This leaves more glycogen available for later in the run and greatly reduces the chance of hitting the wall.

Increase your long run distance slowly and consistently. Most marathon programmes peak at between 18 and 22 miles. Even if you don’t reach the full race distance in training, your body will learn to manage energy far better through these longer sessions.

Include Tempo Runs

Tempo runs teach you to hold a comfortably hard pace for extended time. This improves lactate threshold, running economy, and metabolic efficiency. The better you become at running this pace, the more comfortable marathon pace will feel, and the less glycogen you will burn early on.

Tempo runs are one of the best ways to reduce late race fatigue because they improve how your muscles process energy during sustained effort.

Add Easy Miles

Easy running builds aerobic capacity, strengthens the heart, and increases the number of mitochondria in your muscles. These are the tiny energy centres that convert fuel into usable energy. More mitochondria means your body uses energy more effectively and burns fat at higher intensities. This delays the wall and keeps you moving smoothly for longer.

Strength and Conditioning Helps Too

Stronger muscles waste less energy. They absorb impact better, hold form for longer, and reduce unnecessary movement. All of this reduces the energy cost of running. When your form collapses late in a race, your body burns more calories to maintain pace. Strength work prevents that.

Include squats, deadlifts, lunges, calf raises, and core exercises. Two sessions per week is enough to see a real difference. Take a look at our post on strength and conditioning for runners to learn more.

The Pacing Mistakes That Lead to the Wall

Even the best fuelling and training can be undone by poor pacing. Starting too fast is one of the biggest reasons runners crash late in a race.

Start Slower Than You Think

The first few miles of a race feel easy. Adrenaline is high, the crowd is loud, and you feel fresher than you have in months. This is the most dangerous moment.

If you run even thirty seconds per km too fast in the early stages, you will burn through glycogen far quicker than planned. Your body cannot recover from this later in the race. Even if you slow down, the damage has been done.

The best long distance races are the ones with even splits or slight negative splits. Start a little slower than your target pace, settle in, and build gradually.

Run to Feel as Well as Pace

Watches are useful, but they do not know how your body feels. Some days you may need to run by effort rather than pace. On windy, hot, or humid days, your effort level may rise even if your watch says your pace is right. Trust how your body feels and adjust early rather than paying for it later.

Use Training to Learn What Sustainable Feels Like

Long runs, tempo sessions, and marathon pace efforts teach you what sustainable effort feels like. You should finish marathon pace sections feeling like you could go a little further, not like you are hanging on. Training gives you the confidence to trust your pacing strategy on race day.

Hydration and Electrolytes Matter More Than Most Runners Realise

Dehydration and low electrolytes magnify the effects of hitting the wall. If your hydration levels drop too far, your heart rate rises, your blood volume falls, and your muscles struggle to contract efficiently. This makes running feel more difficult and glycogen depletion feel worse.

Sip water regularly during long runs and races and don’t forget electrolytes. If the weather is warm or you’re a heavy sweater consider taking more water and increasing your electrolytes. Salt supports muscle function and helps your body absorb fluids more effectively. Many runners use a mix of water, gels, and electrolyte drinks spread throughout the run.

The Mental Side of Avoiding the Wall

Hitting the wall is physical, but it has a strong mental component. When your body starts to tire late in a race, your brain becomes more protective, and negative thoughts can take over, including a stronger desire to stop. Training your mind helps you stay calm and focused when you feel the early signs of fatigue.

Useful strategies include:

• Break the race into small sections
  
  

• Focus on form rather than pace when fatigue rises
  
  

• Train with tough sessions that build resilience
  
  

• Practise running on tired legs during back to back sessions

Mental resilience does not eliminate the wall, but it stops you from panicking and burning extra energy at the point where you need calm.

Race Day Preparation That Prevents the Wall

The final piece is how you approach the day of the race itself.

• Eat well the day before
  
  

• Stick to familiar foods
  
  

• Do not try new gels on race day
  
  

• Check the weather and adjust pace, fluids and electrolyte intake as needed
  
  

• Take a gel 15-20 minutes before the start and stick to your fuelling strategy
  
  

• Start slower than you feel you should
  
  

• Use aid stations for small top-ups
  
  

• Stay relaxed and in control

Everything you do on race day should support the fuel and pacing strategy that you have practised.

Bringing It All Together

Avoiding the wall is not about one single trick. It is about combining fuelling, training, pacing, hydration, and mental preparation into a consistent approach. Every part supports the others. When you plan your fuel, your pacing is sensible, your long runs are consistent, your gels are taken at the right time, and the wall simply never arrives.

The goal is not to feel amazing for the whole race. Long distance running will always involve some level of discomfort. The goal is to avoid the sudden, overwhelming shutdown that comes with glycogen depletion. When you get all of these elements right, you finish strong rather than simply surviving the final miles.