Triathlon nutrition guide
Nutrition affects most aspects of our training and racing. It is without doubt one of the most important aspects of race preparation. Yet, athletes typically spend far more time thinking about training than about nutrition. Hours and hours are spent in the pool, on the bike, and on the trails. Far less time is spent on careful nutrition planning. Here we will go through all the important aspects.
Nutrition: The 4th discipline
Nutrition is sometimes called the 4th discipline, and rightly so. Nutrition can be the fine line between winning and not even finishing a race. Athletes will often discuss nutrition-related issues when they have not performed their best: “I ran out of energy on the bike”, “my stomach was churning for the last 2km”, or “I tried a new gel I hadn’t used in training”.
Although nutrition is often considered complex, it is in fact simple if we stick to the science and make evidence-based decisions. This guide will give you the background information and guide you to a successful nutrition strategy.
Race nutrition versus training nutrition
First, it is important to distinguish the goals of race nutrition and training nutrition. Race nutrition is all about performance – how can we go faster on race day? Training nutrition may not always be about performance; it is about promoting training adaptations, health, and supporting specific training goals. This means that nutrition recommendations may be different around race and during training days. For example, athletes who often experience gastro-intestinal (stomach) problems are advised to reduce fiber intake in close proximity to a race. In contrast, during periods of training, athletes are advised to have a high fiber intake as this will promote good gut function and overall health.
We will discuss race nutrition first, followed by training nutrition.
RACE NUTRITION
What is important when considering race nutrition? The main factors that affect performance are
- Fuel
- Hydration
- Stomach comfort
Running out of fuel
We have all experienced this sensation in training or racing. Suddenly the power in our legs disappears. We may feel dizzy and even nauseous. Although we may still be able to finish, we have to go much slower. When this happens, it is often related to running out of fuel.
Dehydration
The faster we run and the more power we produce on the bike, the more heat is produced. To account for this heat, production, we sweat in order to stay cool. In hot conditions, sweating may be the only way we can cool down our bodies. However, when we lose too much sweat and become dehydrated it becomes harder to maintain body temperature. Some degree of dehydration is unlikely to be a problem but loosing ≥3% of your body weight, your performance may be affected.
GI-issues
The third reason why athletes struggle during races (or training) is that their gut starts to play up. Apart from the discomfort, which can range from mild to extreme, it becomes difficult to eat and drink and that can affect performance later in the race.
BACK TO BASICS
Fuels
The body uses two main fuels: carbohydrate and fat. Even the leanest athlete has sufficient fat to sustain the longest races, but carbohydrate reserves are limited. Yet, carbohydrate is the most important fuel as it is necessary for higher intensity exercise: it is the performance fuel. Carbohydrate can deliver energy faster to the muscles than fats. Unfortunately, carbohydrate stores can normally support only 2-3 hours of exercise (dependent on the intensity). Carbohydrate is stored in the body as glycogen in the muscle and in liver. In the muscle we have roughly 500-800 grams and is possible to run out of carbohydrate in less than 2 hours. Running out of fuel is often called “bonking” or referred to as “hitting the wall”.
Key points: Carbohydrate is the performance fuel
Key point: Carbohydrate stores are small and therefore need to be topped up
Hitting the wall
Many athletes have experienced hitting the wall or bonking. Suddenly all energy seems to flow away, accompanied by dizziness, sometimes nausea and becomes impossible to maintain a good pace. Marathon runners refer to this as hitting the wall and typically occurs around the 32km (20 mile) mark during the marathon. The reason this happens is that the body has run out of carbohydrate and has to continue with fats as the main fuel. There are a few simple strategies that can delay, or completely prevent this from happening. First ensuring you start the race with optimal glycogen stores and secondly topping up during the race (using drinks, gels and/or solid foods).
Carb-loading
In order to start a race with optimal glycogen stores it is important to eat carbohydrate-rich foods the day or days before the race. Usually, training is much reduced the days before the race, and carbohydrate intake should be increased. Traditionally this has been called carbo-loading. You are essentially filling up your muscle glycogen stores. Below are some examples of good carbohydrate sources before race day. Although it is important to have a relatively high carbohydrate intake, it is also important that you realize that carbo-loading is not the same as overeating!
Good carbohydrate sources for race day
Refined grains (white rice)cooked cereals corn/rice based cerealswhite bread, bagels (no seeded breads)pancakescooked veggies (no seeds)cooked potatoesripe bananascooked fruits, applesauce/fruit blendslean meatrice cakeshoneysyruppulp-free juice
Breakfast
When you wake up in the morning your liver glycogen is low. Your body uses liver glycogen overnight, so it is essential to make sure you replenish liver glycogen stores. During your race the liver will provide carbohydrate to maintain your blood sugar and prevent hypoglycemia (low blood sugar, resulting in dizziness, weakness etc). This is where breakfast comes in. You can optimize liver glycogen stores by ingesting 100-200 grams of carbohydrate in the 3-4 hours before the start of your race (though practice this in training before you race). Some athletes find it difficult to eat before a race and they could benefit from obtaining carbohydrates from drinks. Selecting carbohydrate-rich foods that are low in fiber, fat, and protein can reduce stomach problems. This is especially important for athletes who frequently experience stomach discomfort during a race.
Nutrition just before the start
You can continue to top up your liver glycogen stores in the hour before you start. Most of the carbohydrate you ingest here will become available to the muscle during the swim. So, anything that is ingested shortly before the start is part of your nutrition during exercise because it takes time for it to be digested and absorbed. What you pick as your chosen fuel depends on personal preferences as well as the overall nutrition plan. It is often recommended to take something in the last 10 min before the start. Again, athletes prone to stomach discomfort should opt for easily digested carbohydrate sources. For example, a gel containing 25-30 grams of carbohydrate.
Many athletes do not have as much as 100-200g carbs for breakfast pre-race Pre-race breakfast needs to be practiced in training. Practice this regularly in training.
HOW TO DEVELOP YOUR OWN RACE NUTRITION PLAN
Race nutrition requires a bit of planning. During longer races your target carbohydrate intake should be higher than shorter races. In races over 2 hours you can benefit from consuming roughly 60 grams of carbohydrate per hour. In events longer than 3h it is worth considering even higher intake, However, this effect can only be achieved if you use specific carbohydrate blends (for example, glucose + fructose). It is beyond the scope of this guide to discuss this in more detail but you can find more information on www.mysportscience.com. (EXACT LINK WILL FOLLOW)
Carbohydrates can come from various sources (drinks, gels, bars and other foods). What is best mostly depends on personal preference. It is important to study what is available on course and develop a plan that takes into account foods and drinks you will collect on course and foods and drinks you will have to bring yourself.
Drinks, gels or bars?
Bars
Solid foods usually provide more carbohydrate per unit of weight and are therefore a very effective energy source to carry. It is recommended to select energy bars that are low in fat, fiber and protein as these ingredients will slow down gastric emptying and may contribute to stomach problems. Solid food is great in preventing an empty feeling in the stomach that many athletes experience during later stages of a race. It comes down to personal preference whether you want to chew food during a race or not. Some athletes struggle to chew food during a race and prefer to get their carbohydrates from gels or drinks.
Gels
Gels are a compact form energy. A small volume of fluid with a relatively large amount of carbohydrate. Gels typically deliver 20-25 grams of carbohydrate and come in many different flavors. Gels may be caffeinated or non-caffeinated. It is important to realize that gels need to be ingested with sufficient water to make sure gastric emptying is fast and no stomach problems develop.
Carbohydrate drinks
Carbohydrate drinks typically contain carbohydrate in concentrations of 6-7%. This means that the drink contains 60-70 grams of carbohydrate per liter of fluid. A regular sports bottle of 600ml (20 oz.) will therefore deliver roughly 35 grams of carbohydrate. A sports drink also contains some sodium (and other electrolytes) which can be beneficial for the absorption of fluid (as we will see under hydration).
What drinks, gels and bars to choose…
This depends on factors like practicalities, preferences and tolerance. If you want to make use of the nutrition offered by race organizers, it is usually recommended to also train with that brand. If you are planning to take in more than 60 grams of carbohydrate per hour, check that the ratio of glucose:fructose is 2:1 or similar.
For help with your nutrition planning use YABADU. Select the Challenge race and you will see that the software recognizes not only what products will be served in a race but also where the feed stations are. The planner also helps to calculate how much you need and tells you when best to take it. And it is free for Challenge race participants.
Caffeine
Many athletes use caffeine before or during a race to boost their performance. Although there may be individual differences in tolerance and perception, using caffeine to enhance performance is indeed supported by scientific evidence. Studies have demonstrated that relatively small amounts of caffeine are required to give optimal effects. For example, consuming 3 mg of caffeine per kilogram body weight has been found to improve endurance performance. This equates to roughly 200 mg for a 70kg person. There are many different ways to deliver caffeine. Below are some examples. It is important to note that too much caffeine can cause negative side effects (palpitations, nausea, dizziness) and should be avoided. The dose and source of caffeine should be practised in training to reduce the risk of these side effects during a race.
Many athletes abstain from caffeine before a race but research doesn’t support tis practice. The performance effects are similar.
Energy drinks
Energy drinks can be found on the course of many races. Although not specifically designed for rapid absorption and fluid delivery like sports drinks, energy drinks typically deliver two main components: carbohydrate and caffeine. Athletes who are intending to use caffeine can use energy drinks as an alternative source. The carbohydrate concentration in energy drinks is usually high and therefore the advice is the same as with gels, drink sufficient water with it. One potential disadvantage is that energy drinks are usually carbonated and this in turn can cause some gastro-intestinal discomfort. Therefore, it is recommended to practice the use of any drinks used on course in training to make sure they can be tolerated well.
HOW TO DEVELOP A PERSONALIZED HYDRATION STRATEGY
Drink enough but not too much
In order to prevent dehydration it is important to start a race hydrated. Drink at least 500ml the 2 hours before the race, excess water will be eliminated through urine. Double check your urine color is pale. To prevent dehydration during a race, drink at rates similar to your sweat rate. You can easily work out your sweat rate: measure yourself before and after training. Record body weight and correct it for the amount of fluid consumed (see Figure X). If you do this regularly and in different conditions (hot and cold weather conditions), you will get a good idea of your sweat rate. Your target for fluid intake should help you to lose no more than 3% body weight. Drinking to thirst can in some cases achieve this goal as well.
More is not always better
It is even more important not to drink too much. Apart from the negative effects of increased body weight, there is also the potential to dilute your body sodium and develop hyponatremia (low blood sodium). Hyponatremia is a potentially dangerous condition with early symptoms that are very similar to those of dehydration. Having knowledge of your weight loss in training and in different conditions will help you to keep your body weight relatively stable, prevent weight gain and serious dehydration.
Improving fluid delivery
Fluid delivery can be accelerated by adding some carbohydrate to water. Fluid delivery will be impaired if highly concentrated carbohydrate solutions are used. Therefore, if you are using gels, make sure to drink enough water to avoid highly concentrated stomach contents. The same is true for solid foods, such as energy bars.
Electrolytes
There is a lot of hype about electrolytes. There is no doubt that electrolytes play an important role during exercise. But this doesn’t necessarily mean that we need to consume a large amount of electrolytes during exercise. Athletes popping salt tablets has become very common but there is no research to support this practice. All is explained in a series of blogs on mysportscience.com. Whether you need to pay attention to salt intake depends mainly on 3 things:
- Exercise longer than 4 hours (less than 4 hours you don’t need to worry)
- High sweat sodium concentration (your sweat has more than average sodium amounts)
- Your drink plan involves drinking more than 70% of your fluid losses (especially for those sweating a lot this is often not possible. For example: if you sweat 2 L/h, it is unlikely that you could drink more than 1.4L/h)!
HOW TO MINIMISE STOMACH ISSUES
Gastro-intestinal problems
One of the common problems in long distance events is the occurrence of gastro-intestinal problems. Such problems include mild symptoms like gas and burping which are not serious and unlikely to affect performance. Other symptoms like heartburn, diarrhea and bloody stools, nausea and vomiting and uncomfortable bloating are more serious and can have a major effect on performance and even health. Certain individuals are more prone to develop such symptoms than others and this is likely dependent on genetics, biomechanics, anatomy, age, diet and/or health. The exact symptoms are highly individual and often circumstantial. Hot weather, nerves, race intensity, duration, dehydration and poor nutrition can exacerbate the issues. Although in some cases it is difficult to completely prevent some of these symptoms, there are a number of nutritional measures that can be used to minimize the risk. Some of these have already been mentioned: reducing fiber, fat and protein intake before and during the race, avoiding highly concentrated stomach contents (drinking with gels), practicing pre and during race nutrition, managing fluid intake and so on It is important to note that when bloating occurs and fluids seems to accumulate in the stomach, there is no point ingesting more fluids. It is important to manage the situation by reducing the intensity a little and giving the stomach some time to pass fluid on to the intestine for absorption. One key method to reduce stomach problems during a race, is to practice your race nutrition strategy for 6-10 weeks leading up to the event. Either choose your own specific nutrition brand that suits you, or train with products that will be on course. The more you train with carbs, the more you can train your gut to absorb and utilize them….don't be carb phobic (individuals who avoid carbs seem to develop gastro-intestinal problems more frequently and symptoms are more severe).
Train high and train low
Some days it is good to train high (train your race nutrition), other days you may want to experiment with training low (this term is used to refer to training with low carbohydrate availability). Making sure that your body can also perform with fat as a fuel. Training sessions that athletes often include are training without breakfast (training with low liver glycogen) or training twice a day with little carbohydrate intake in between (training with low muscle glycogen). There is evidence that such strategies will enhance the ability to use fat as a fuel. However, it must also be noted that more recovery time is needed; training is harder, and you will be more likely to develop symptoms of overtraining and compromise immune function if done too often. Therefore, these training strategies may not be appropriate for everyone.
General diet
Although on some days there should be a focus on training low, other days there should be focus on training high. In general carbohydrate should be a major component of the diet as it supports recovery and the higher intensity part of training. The exact amount of carbohydrate you need to take in depends on the training. If the training uses more muscle and liver glycogen, your carbohydrate intake should increase accordingly. The following table should give an idea of how much carbohydrate should be ingested on a daily basis.
Recovery
Recovery is an extremely important part of the training process. In fact, this is the period in which the body adapts and improves. Training is just the stimulus to start this process. Nutrition plays an important role here too. If we need to recover quickly before the next training session or race, carbohydrate is the most important ingredient, closely followed by water. If we are looking to improve over time and increase the building of new proteins (protein synthesis to support new and improved muscle), protein is the most important ingredient. Proteins are essential for repair and adaptation. High quality proteins that contain all of the amino acids (the building blocks to make proteins) are best at increasing the synthesis of proteins. Studies have show that 20-25 grams of high-quality protein within 1 hour after exercise and at regular intervals (every 3 hours during the day) should result in optimal protein synthesis. In the long run this would support the adaptations!
Training your race nutrition (or training the gut)
Start to train your nutrition at least 6 weeks before the race (but ideally even longer [10 weeks]). Choose at least one day a week where the goal of the training is to practice your race nutrition strategy. If your plan is to take on 60 grams of carbohydrate per hour in the race, try to go a little higher in training. It is ok, if it feels a little uncomfortable in training, your gut can adapt and you will benefit on race day. When you are training with your race nutrition or you are training to adapt the intestine to absorb more carbohydrate we refer to this as training high.
References
Baker LB, Jeukendrup AE. Optimal composition of fluid-replacement beverages. Compr Physiol. 4(2):575-620, 2014.
Burke LM, Hawley JA, Wong SH, Jeukendrup AE. Carbohydrates for training and competition. J Sports Sci. 29 Suppl 1:S17-27, 2011.
Jeukendrup AE and Gleeson M. Sports nutrition 2nd edition Human Kinetics Champaign IL. 2010 (ISBN-13: 978-0736079624, ISBN-10: 0736079629)
Jeukendrup AE. Carbohydrate and exercise performance: the role of multiple transportable carbohydrates. Curr Opin Clin Nutr Metab Care. 2010 Jul;13(4):452-7, 2010.
Jeukendrup AE. Nutrition for endurance sports: marathon, triathlon, and road cycling. J Sports Sci. 29 Suppl 1:S91-9, 2011.
Jeukendrup A. A step towards personalized sports nutrition: carbohydrate intake during exercise. Sports Med. 44 Suppl 1:S25-33, 2014.
de Oliveira EP, Burini RC, Jeukendrup A. Gastrointestinal complaints during exercise: prevalence, etiology, and nutritional recommendations. Sports Med. 44 Suppl 1:S79-85, 2014
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