Training the gut is an important aspect of sports nutrition.

Gastrointestinal during exercise and especially competitions are something that many athletes experience regularly. Up to the point that they end up avoiding adoption of optimal fueling strategies and thus minimize carbohydrate intake in important exercise sessions. By doing that - performance ends up being way below the potential. So - what causes these issues and what can be done about them?

There are a few important aspects that contribute to the occurrence of these problems:

  • Suboptimal food choices in the days leading to a specific event.
  • Not practicing nutritional strategies used during races.
  • Suboptimal nutrition strategies in races
  • Being scared of the problem and by doing that increase stress levels

Below are some guidelines that will help you train your gut and reduce the incidence of gastrointestinal problems.

Step 1 - Identify The Problem

Identify the problem

The first step towards solving the problem is to identify it - find its cause. Perhaps the problem will disappear by just fixing the diet leading into those problematic exercise bouts.

  • Have you reduced your fiber intake prior to the exercise?
    Fiber is not completely digested and this means that it remains in the gastrointestinal tract. As soon as something goes wrong with digestion, the body will try to get rid of fiber in the gastrointestinal tract and it will make you go to the toilet. Avoid eating fiber in the morning (e.g., instead of oats porridge go with rice) and in the days leading towards the competition (i.e., for up-to 3 days). The food might be very simple but it might actually help with the issue.
  • Do you consume foods high in FODMAP?
    FODMAP stands for fermentable oligosaccharides, disaccharides, monosaccharides and polyols. Sometimes the body simply cannot handle them well and you might want to avoid these foods during and/or before intense exercise sessions.
  • Have you tried changing sports nutrition products used in competitions?
    Very often this solves all the issues as many manufacturers use ingredients that are suboptimal and/or in suboptimal ratios. Sometimes just changing the brand of products used solves the problem on its own. 

Training the Gut - FODMAP Diet

Step 2 - Deal With The Problem

Deal with the problem

Once you know what is causing the issues, it's time to solve them.

Before exercise:

  1. Reduce the amount of fiber 1-3 days before the training session or a race.
  2. Last pre-exercise meal should consist of little to no fiber, little fats and little protein and should focus on carbohydrates. 0.75-1 g/kg for every hour before the start of the session (i.e., 1 g/kg if you have breakfast 60 minutes before the start)

Train the gut

This is a very popular strategy and involves getting the body used to tolerate more carbohydrates. One has to acknowledge at this point that there is a difference between tolerance and absorption of carbohydrates. 

Tolerance means that you can eat plenty of carbohydrates without any issues, whereas absorption means that these carbohydrates actually end up being absorbed and utilised during exercise. While tolerance is crucial for being able to achieve maximal absorption rates, it does not mean that by building tolerance one would be able to increase maximal capacity to absorb carbohydrates. 

How to approach training the gut? A few suggestions below:

  1. Design training sessions so that you are able to execute them without any additional food.
  2. Start eating carbohydrates towards the end of the session and as you get better with this, start to increase the amount and start eating carbohydrates earlier. For instance, start by having a gel 30 minutes before the end of the session. If feeling OK, next time you can start with a gel 60 minutes before the end of the session and have the next one 30 minutes before the end.
  3. Slowly progress with this to the point that you achieve the desired CHO intake without issues.
  4. Try a similar strategy in more intense sessions and try to eat even more than advised to build the tolerance.
  5. Ingest up to two Nrgy Units per hour even during short and less intense training sessions.

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