From The Coaches: No Gut Training, No Glory

As endurance athletes we tend to be a “picky” bunch. We spend hours picking out the perfect bike, getting the perfect aero position, devote time to finding just the right chamois for all those hours in the saddle for training, and let’s not forget time spent analyzing and comparing all that training data. We leave no stone unturned when it comes to our equipment and what works best for us, and yet, we will devote more time to filling our water bottles than we will to developing a solid nutrition plan and strategy for use on our training or race day. Your nutrition can be the single source to win or lose your goal event. Proper fueling is not an accident, it must be tried and tested before race day to make your body work best for you. Let’s chat a little about what you can do to ensure a happy gut on race day.

Avoiding gastric distress: Gastrointestinal Distress: is most commonly defined as a reduction in gastrointestinal blood flow (circulation) due to a buildup of lactic acid in the blood and blood volume demands of the working muscles. This buildup of lactic acid results in the inability of the digestive system to effectively breakdown and process food, absorb nutrients to be used as fuel and clear the bowel. Peristalsis (The wave like muscle contractions in the intestine that help clear the bowel) is greatly compromised during gastric distress and can even cease until blood lactic levels return to normal. The onset of Gastric Distress differs for every athlete and this is why it is important to practice your nutrition in training and not on race day. In general, most athletes will start to develop GI distress at 120 -180 minutes into race pace training or racing. Symptoms include: nausea, diarrhea, stomach cramps and pains, bloating and burping. Almost all endurance athletes will experience gastric distress and women are more likely than men to experience GI distress.
Upper GI distress manifests as heartburn, vomiting, belching, bloating, nausea and/or stomach pain, inability to eat or keep down food.
Lower GI distress includes cramping, gas, urgency and diarrhea, vomiting.
How does Gastric Distress affect my training/ racing? Most athletes have found themselves out on a training run or ride searching for a corner store to buy a Coke or begging a gel or bar off a training buddy deep in the fog of bonking or cramping and it was a very long ride or run home. As we all know, the training post a “bonk” is pretty much useless and leaves you pretty sore and tired afterwards. The fundamental goal for fueling as an endurance athlete is that we want to maintain the most consistent blood sugar levels as possible for maximum use of the muscles, circulation and power output. This principle is also used in avoiding gastric distress. As we train the body builds up lactic acid in the muscles and we are in a race against time to fuel our body with electrolytes and carbohydrates before our GI system shuts down due to lack of blood flow as the body continues to buildup lactic acid. Most of your solid foods should be consumed in the first 120 minutes of a prolonged race or during training. This fueling should include carbohydrates and electrolytes for the body to use as long term fuel during the event. Continued fueling past this point should include soft foods such as chews, gels and liquids.

When training, practice what and when you will be eating. Don’t forget pre-race nutrition starting the week before your goal event. Glycogen stores, hydration and even the amount of sleep you get all impact your body many days out from your goal event.

A Few Tips for Nutrition Success on Race Day:

  1. Topping off the Tank:
    It takes 3 days to properly top up your glycogen stores so don’t depend on that “Pre Race Pasta Carb Loading Party” to take you successfully through your event. If anything it will shift your digestive, circulatory system and pancreas into overdrive all night in order to process all those carbohydrates leaving you with a tired body that has had to work overtime to process a heavy carbohydrate laden meal the night before. Optimally you are looking for an even “slow burn” metabolism that has been on cruise control to break down your meal and easily digested needed nutrients all night leading into race day

  2. Timing your Race Day nutrition:
    Your pre-race meal should take place at least 2 hours before your event and consist of simple protein and carbohydrates. The amount of protein is something that can be very individual, based on tolerance, so training is imperative. Try a peanut butter sandwich, egg whites on toast or protein shake. Avoid cheese as a source of protein or heavy dairy as they are taxing on your digestive system to break down and use for fuel.

  3. Probiotics:
    Endurance athletes put their bodies to the test repeatedly for weeks on end. This long term training causes the digestive system to be taxed and drained of the good bacteria and flora that breaks down the consumed food to be used as fuel. A probiotic is simply a dose of “good bugs” or bacteria to replenish our gut and help the digestive system break down the nutrients to be used by the body.

  4. Fruits may not be friends on race day:
    The week before the goal event you can utilize fruit as a natural source of energy and vitamins but fructose is harder to digest and usually contains a good bit of fiber which is not ideal for race day. The fiber in the fruit negates the effectiveness of carbohydrates so limiting fiber for a greater use of carbohydrates will reap gains on race day. If you have a bit of congestion, fruit juices can sometimes increase phlegm which could make breathing or swallowing a bit more labored.

  5. Avoid dairy on race day:
    As we touched on above, the proteins in dairy products are harder to break down and will take longer to digest than other foods and cause more energy to be used by your endocrine and digestive system that could be sourced by your muscular system.

  6. Mighty Magnesium!
    Magnesium is a proven natural source to help the body buffer lactic acid build up and prevent cramping. Dried Apricots are a great source of concentrated magnesium. You can also use a magnesium supplement that is covered in oyster shell calcium (for better absorption) as a daily supplement. The magnesium source should be consumed at least 3-4 days before the goal event if not taken every day.

  7. Hydrate, Hydrate, Hydrate.
    Once again you cannot make up deficits in hydration on race day or even the night before. Your hydration plan should be in action no later than 5 days before your goal event. If properly hydrated, your blood volume will have better fluidity adding circulation. The better your circulation to your muscles the more power you can put out and the longer you can delay the onset of gastric distress.

Nutrition and tolerances are very individual, and every athlete has their favorite “go to” that gets them through a tough training or racing day. In this time of cancelled events and quarantine provides a perfect opportunity to practice nutrition strategies and what works best. Jump in and work on your gut health and get ready for future glory to come!


Thanks! I have always been pretty good at knowing my body and what it will tolerate on “race day” but there are a few things in here for my to implement! #youdontknowwhatyoudontknow

1 Like

My races are all typically 8 hours+ in duration and I have yet to find anything that works better for me than pb&j sandwiches with banana slices in them on white bread and some scratch labs fuel mix in my bottles. Small wraps with hummus and olives works well for me as well but, I can’t eat them for quite that long. Gels have started wreaking havoc on my body so I tend to stay away from them as much as possible despite how convenient they are to carry.

That is an interesting article, thank you, coach Simon. I knew many of the what’s but non of the why’s
I quickly lose appetite for anything solid or “heavy” so I drink half strength energy drink. After the effort I often crave dairy, a litre of milk, or large pot of unsweetened yoghurt.After a couple of hours to settle down I am ready to eat anything

I’d add RE supplements with probiotics it is worth looking for ones that can give you approx 3 billion viable spores/bacteria per day.

Other supplements I think are incredibly beneficial for sporting performance as well as general health include high strength vitamin D (4000-5000iu/day)… I can talk for hours on vitamin D but it’s such a powerful nutrient!), omega 3 (aim for 2g of EPA and DHA per day) and also high quality B12 (preferably as a drop form or lozenge rather than a tablet or capsule to aid absorption).


Sounds like you are totally on the right path with your nutrition strategies. The whole foods should serve you well. The duration of your races does pose a challenge. A few suggestions that you may want to try in training would be frozen grapes (they do have fiber), rice cakes with either scrambled egg and a bit of ham and brown sugar, a bag of small hard candy that can dissolve in your mouth (small enough not to be a chocking hazard) , small plain pancakes or you can add a spread and use 2 to make a small sandwich. If you want the sugar content of a soda but not the fizz, set it out open a few hours before your race and then pour in your bottle, the carbonation will be gone but you will still get the taste and sugar to wake the body up and a palatal response.

Nutrition is all about practicing and testing what you body tolerates best. Protein will help stabilize your carbohydrates and in turn make them last longer so try to include protein whenever possible early in the race. For every gram of fiber in a food you can subtract 1 gram of carbohydrate so be mindful when planning your intake numbers.

Your doing well with your planning. Never try anything new on race day and for your races they key will be staying hydrated and fueling early for later use when lactic acid levels rise.

All the best!


Thank you for taking the time to read the article. Your experiences are very common and you have adjusted your intake well. Being able to tolerate dairy in large amounts is pretty unusual but if you can, that’s great, your body can use the recovery protein. I would be sure to throw in some carbohydrates or sugars for quicker absorption to aid your recovery but otherwise, stick with what has been working for you!


Hello Ross, I also recommend probiotics to athletes to aid with not only gut health and digestion but there are some studies which show that it can also fight off some respiratory track bugs as well.

Supplements can aid with overall health and the daily stresses of training. Tolerances are very individual so again, these should be tried while you have a training block and not right before a race. There are limits to how much of a supplement you take before a positive becomes a negative. The big consideration that must be addressed with supplements is their purity. Always be sure your supplement is batch tested and from an approved and trusted source.


Totally agree, and yes, there is plenty of evidence to show probiotics can help with not just respiratory tract infections but infections in general. The gut plays a huge, huge role with our immune system, something that is often not realised by many.

I’m a chiropractor but nutrition and exercise physiology are two topics I am very passionate about and am always keen to expand my knowledge :slight_smile:



Eating to Suffer has various recommendations for carbohydrate consumption for the previous day for certain workouts. Are those recommendations above what you normally eat? Or are they there to ensure that your daily consumption of carbohydrates reaches that amount?

Those recommendations are NOT above what you would normally eat. Those are guidelines for carbohydrate intake for the day.