by Mark Wolff

In the world of endurance sport the term “Hitting the Wall” or ‘Bonking” is quite common among athletes. Most of us have experienced it at some time or another and then others quite frequently. To explain what “Hitting the Wall” is in short is the point at which your muscle and liver glycogen stores are completely depleted. It leaves one feeling fatigued, in a world of hurt and pain with absolutely no energy or will and desire to continue. Its not a pleasant experience and certainly a moment we would rather not be in.  You see the human body has two main fuel tanks, glycogen and fat. Glycogen which is mainly stored in the muscle and liver has around 2000 calories of fuel while our fat stores contain around 40 000 Calories of energy. If you think about it in logical terms burning off around >1000 calories of glycogen fuel per an hour of exercise is not going to not last you very long. During exercise though a combination of fuel tanks are used BUT this is dependent on intensity, time and type of fuel consumption. To really understand this Click Here to watch my explanation of fuel tank usage in detail.Everyone fears hitting the wall, BUT I am going to advise you how to prevent it ;-).

I always say train as you are going to race. Over time, this will adapt the body and work the muscles holistically enabling you to cope with the distance and the terrain on the day. Ensure that you incorporate the same speed work in your training that you will be racing at and make sure you do the necessary hill and speed work as well! Ever heard of the expression “train hard race easy”? This takes weeks of preparation; so don’t leave it to the last minute!

Too many egos cause havoc. Don’t push yourself over your limits to prove a point. Race at the pace you have trained at! It is important to make sure not to race at a faster pace than your body can cope with because the minute that happens you will start depleting your glycogen fuel rapidly. This could result in the inevitable bonk that will hit you when you least expect it.

Make sure you fuel properly! Basically you need to understand what is required from a nutrition perspective on the day to ensure your energy levels are topped up and carry you through the event. You need to prepare for this in advance, as its not something you can decide to leave for the week of the event. Nutrition preparation needs to begin way before the event. Weeks in advance of the event you should have a proper fuelling plan in place and stick to it on the day. 

I have given you three major ways on how not to bonk, but I am going to expand on the nutrition training and explain where your focus needs to be. Whether a race snake or a weekend warrior there are considerations to meet your needs.


The 3 main points on proper fuelling is:

  1. Keep it Simple
  2. Take in controlled amounts to achieve the greatest result (DO NOT OVERDO IT)
  3. Plan, Test, Use.

Of course, the way a race snake fuels in comparison to a weekend warrior is very different and each method needs to work according to what you want to achieve.
The pace and time you are going at will ultimately determine the type of fuel you require. I see way too many cyclist or runners going at lower to medium intensities and they start to fuel themselves with very high intensity fuel. All this does is creates havoc with the system, causing dreaded spikes, crashes and very often leading to symptoms of digestive discomfort and nausea.

There is no one fix all fueling approach and no matter what anyone tells you what to take and how to take it, you need to look at fueling from your own unique requirements. Many supplement companies advise athletes what to consume and how often, to get to the finish line. However, many of these companies don’t consider the actual type of athlete, their individual capabilities, the duration and intensity of their performance as well as their personal preferences. This is where we I differ completely. I get to know an athlete before advising them on any fueling strategy.

Unfortunately, it’s difficult for me to speak to you each as individuals in a knowledge sharing piece like this, but I will do my best to provide you with a direction and options you can consider as part of your own fueling strategy.

The first thing you need to ask yourself realistically is what sort of time goal are you going for during your race? Duration and intensity will ultimately determine your fuel intake. Then you need to decide what your dietary preferences are from a texture point of view. Are you the kind of athlete that likes to eat solids, or the kind that prefers a liquid feed or a combination of both as nutritional comfort is an important factor to consider. If you are going at a really high intensity and breathing is extremely heavy during the event you might want to consider a liquid or combination feed as chewing is not so simple and the airways need to be kept open. However if you are going at a controlled pace or a combination pace then you will have the ability to consume food solids.


1. How often should you fuel?
Timing of nutrition intake is critical in any endurance sport. This should be frequent and planned.

2. How much should you be consuming?
The amount of nutrition consumed will be determined by a few factors mainly based on weight, duration and intensity.

3. What fuel should I be using?
Type of fuel is personal, as mentioned above. Lets break this down some more.

Eat small and frequently (measure your food intake by time). Frequent consumption is the key to a decent endurance event. Once you are in a comfort zone, meaning a point of equilibrium where aerobic engine is stable, breathing is regulated and comfortable and you are in a rhythm, it’s time to feed. Generally I would say around 20 minutes or more you will start to hit this but it depends on the individual. Staggered or drip feeding is the best way to fuel as it keeps the energy system a lot more stable over time and its far easier on the digestive system. On the other hand, planning your nutrition intake by time makes it very structured and easy to stick to there is no guess work involved.

In endurance events there are many theories around the 60-90 grams of carbs per an hour. Maximizing absorption rate with the correct combination of carbohydrates and even trying to go beyond that. It’s certainly not about how many carbs you can fit in your mouth but what your unique body is capable of absorbing and utilising. Do not fall into this category of can over eater it will ruin your day. Plan this properly. If you consume 60 grams of carbs per an hour or less in training and then on race day take 90 grams of carbs in per an hour you will head for absolute disaster. You have not trained your gut to deal with this volume of nutrition intake. In the fuel guide I will provide you I have worked out an average amount of consumption based on the type of athlete you are. Most importantly is to test this out during training and not to arrive at the event without having tested the fuelling strategy a few times. Failing to arrive prepared from a nutrition point of view will not be a pleasant day out. Ensure the volume of carbohydrates per an hour is consumed over time and its the correct amount that your digestive system coped with in training

As explained earlier the human body has a large amount of fat (40 000 calories) as an incredible source of energy and most nutrition experts forget to take that into account as well. The glycogen tank contains around 2000 calories of fuel when topped up. As shown in my video on the Fuel Tank explanation if you are going at a high intensity and burning off approximately 1200 calories per an hour you know your glycogen tank is not going to last more than 90 minutes. However at a slightly lower or controlled or combination pace your tank will use a higher combination of fat with glycogen and your tank will last longer. The other way to spare glycogen is to take in nutrition and this can spare it to around approximately 30%.
I think you get the picture here which is a high intensity performing athlete will require a fast releasing carbohydrate feed while a lower intensity athlete can use more stabilizing carbohydrates which are non-spiking. But I bet no one has ever told you this. All they said is take gels no matter what kind of an athlete you are. Its the worst possible advice. You need to fuel your effort and duration correctly but also with the right combination of correct carbohydrates for the type of person that you are. Again, I cannot stress the point enough to test out your nutrition in training and many weeks before the event to get familiar and comfortable with the fuelling strategy.

Now I am not going to leave you there ;-).

Along with 32Gi I have designed a basic cycling fuelling guide for your big day.
Your job is to be realistic about your personal performance goals, consider the personal factors and then select the right fuelling guide for you. Of course if you have any questions I am there to help.  NOT ONLY have I provided you an awesome guide to fuelling but I managed to twist the arms of the  head honchos at 32Gi who have agreed to offer some one time incredible deals to take advantage of should you decide to take your fuelling strategy in that direction.

I have TWO Options for you to choose from:

Are you a WEEKEND WARRIOR or a RACE SNAKE (Click on the relevant option to get your Fuel Guide)


Once you are satisfied with your FUEL GUIDE you can


Train Safe, Plan Properly


All the best


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Otto Muller Ueckermann October 15, 2017 - 10:56 am

Thank you

Phikisile October 21, 2017 - 7:18 pm

Thanks I learn a lot


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