How to fuel an endurance race

How to fuel an endurance race

As an endurance competitor, you push your body to its limits. You understand the importance of training, but do you give the same attention to what fuels your body? Nutrition is more than just eating right; it’s about understanding the complex relationship between your food, your gut, and your performance. Ultra distance events challenge you in unique ways. The long hours of training and the intense physical demands require not just physical strength but also a well-strategised nutritional approach. The ability to keep fuelling may well be the determining factor of whether you complete the race or not.

It’s important to understand that the body varies the type of fuel it utilizes depending on the intensity and duration of the activity. During shorter or high-intensity sessions above 75% VO2 max, the body relies heavily on glycogen stores. During prolonged exercise at a low to moderate intensity (35% of VO2max), most of the energy requirements for skeletal muscle can be met from predominantly Fatty Acid (FA) oxidation, with a very small contribution from glucose oxidation. The diagram below illustrates this.

Thus for a long distance ultra run the body will be consuming both carbohydrates and fats and the majority of people, will be leaning towards a higher fat burning rate, particularly for the longer ultras of 50 miles upwards.

It makes sense then, that for these longer, lower intensity runs you should consume a combination of carbohydrates, protein and fats to provide the optimal balance of macro nutrients to fuel your body over these distances.  And it’s no coincidence that this is what our bodies have evolved to eat.

As a guide, for ultras, most people should try to consume 40-80g (elite athletes even more) of carbohydrate per hour (tolerance and body weight dependent) and 200-300 calories or more per hour.  This sounds straightforward, but for many, this is not that easy to maintain over extended periods due to a number of factors.  Studies have shown that around 60-80% of ultra runners will experience Gastro Intestinal distress during races which will make eating and drinking difficult.  During exercise the blood moves away from the gut to the limbs which makes digestion more difficult.  Dehydration exacerbates the reduced blood flow and increases the difficulty for the gut to digest food. In addition, the constant jarring and repetitive motion of running can also add to the GI distress.  It therefore often becomes more difficult to eat the further into the race you get but there are ways to improve your chances of avoiding or reducing the effects of GI distress.

Keep well hydrated to aid blood flow to the gut. Eat small amounts but often to try to maintain the calorie and carbohydrate intake figures provided earlier. To do this you will need to experiment with eating during your training to find the foods that you are able to tolerate for long periods of time.  It is best to have a good variety of sweet and savoury foods that remain appetizing even when you are not keen to eat.  This is likely to be in the form of carbohydrate and electrolyte drinks, energy bars, chews and gels and different easy to eat sweet and savoury whole foods or snacks.  Unsurprisingly, studies have shown that those who are able to drink and eat more throughout the course of an ultra race perform better overall.  It is also vitally important to replace electrolytes lost through sweating throughout the race and, again, as everyone sweats at different rates and lose different % of salts, you will need to experiment to find the best foods and supplements that you are able to consume over long periods that your body can tolerate to replace sodium, magnesium and potassium losses. Sweat testing is available to determine what levels of electrolytes are lost when you sweat to better inform what you need to be consuming during training and races.

Whilst there is a lot of focus on carbohydrates for fuelling, the importance of protein and fats are often overlooked during training and racing.  The International Society of Sports Nutrition recommends 5-10g of protein per hour when racing.  Many sports nutrition energy supplements are carbohydrate heavy and contain little protein (less those aimed at recovery), thus, you will need to consider how you will supplement the sports nutrition with other products, and real food is often the best way to do that. Seeds and nuts are high in protein and fats as are many dairy products, meat, eggs and fish. There are also a plethora of high protein nutrition products in the form of drinks, bars and powders.  Whilst whole foods are the healthiest form of nutrition for us, the likes of meat will take a long time to break down and digest and may not sit well in the stomach whilst running, so it’s very much experimentation again to find the right protein choices.

Supernatural Fuel energy pouches are designed for endurance sports and have a number of benefits over other nutrition products on the market:

  • They are made from organic blended whole foods so they are nutritious and have no GMO or pesticides.
  • They contain carbohydrates, protein and fats, all the macro nutrients needed to fuel your body for prolonged periods.
  • They are blends so easier to eat and digest on the move than bars and other solid foods.
  • Because they contain complex and simple carbohydrates as well as protein and fats they provide prolonged energy release when compared to glucose/fructose gels which provide spikes and subsequent drops in energy.
  • They have had minimal processing have no additives whatsoever, so they sit well in your stomach and won’t contribute to GI issues.

Our Dates & Sesame pouch, which has the best nutritional mix contains 23g of carbohydrate, 5g of protein and 11g of good fats (total 212kcals) , so perfect for those long days out with some additional   carbohydrate sources to maintain your energy levels to the finish.

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