Gut Issues, GI-Maps and the Endurance Athlete

Digestive Health and the GI-MAP

We know this will be a huge relief to a lot of the athletes we work with here at Athlete Nutrition Coach. The latest in digestive health functional testing has already given some of our elite athletes the answers to an extremely frustrating and performance damaging issue

What are the common digestive issues we see?

Most endurance athletes we work with will have some digestive complaint that’s getting in their way – be that during training or after every meal.

  • Bloating and excessive wind
  • Cramps and discomfort towards the end of a long ride/race
  • Loose stool, diarrhea or constipation
  • Reflux after pre-training meal

A lot of them will come to us with food intolerance tests that truly have the most bizarre assortment of foods the athlete is supposed to avoid.

What else can be affected?

Unfortunately – it’s rarely the food that’s the issue – it’ll be the gut – and no matter what you avoid – if it’s an unhealthy environment, it’ll be affecting you in more ways than just digestive discomfort.

  • Fatigue
  • Low libido
  • Mood disturbances and anxiety
  • Problems sleeping 

What are the causes?

We’ll always explain about the stresses endurance exercise puts on the digestive system. A massive proportion of gut blood flow is redirected to the working muscles at even moderate intensities.

That leads to a host of activity which affects the natural function of the gut. The barrier of the GI tract can become damaged causing an inflammatory response to endotoxins leaking out.

The mechanical stress like being in an aero position or josling of stomach contents during running can have adverse effects.

And of course the psychological effect we spoke about before in a previous blog – how the gut brain axis gets disrupted due to stress causing disturbances to the ebb and flow of the GI tract.

The standard diet of the endurance athlete who relies heavily on processed carbohydrates such as gels and powders has a major effect on the gut microbiome which isn’t as robust and diverse 

So what’s the answer?

That’s why a GI-MAP can be the holy grail to the athlete who has tried every restriction/ diet and protocol and still hasn’t gotten to the bottom of their digestive issues.

It’s the only way of seeing a complete picture of digestive health from a single stool sample 

The GI-MAP is designed to detect bacteria, pathogens, viral infections, fungi and parasites that may be disturbing normal microbial balance.

A disturbance to each of these factors can contribute to illness as well as 

  • Digestion including all the issues outlined above above
  • nutrient absorption – no matter how varied your diet is if you can’t absorb the nutrients it can lead to a deficiency
  • Hormones responsible for metabolic processes such as insulin sensitivity, glucose tolerance, fat storage, and appetite are produced in the gut
  • Inflammation such as IBD and IBS
  • Immune disturbances even autoimmune diseases

We know first hand how much effort goes into training and competing at the highest level – and even if you just want to enjoy exercise for the fun and freedom of it. It can feel like any change makes zero improvement so you just manage your symptoms now you can treat the source of the problem!

This is just one of the industry leading functional tests now available to clients of Athlete Nutrition Coach


Breit S, Kupferberg A, Rogler G and Hasler G (2018) Vagus Nerve as Modulator of the Brain–Gut Axis in Psychiatric and Inflammatory Disorders. Front. Psychiatry 9:44.

Hughes RL (2020) A Review of the Role of the Gut Microbiome in Personalized Sports Nutrition. Front. Nutr. 6:191.

Sohail MU, Yassine HM, Sohail A, Al Thani AA. Impact of Physical Exercise on Gut Microbiome, Inflammation, and the Pathobiology of Metabolic Disorders. Rev Diabet Stud. 2019;15:35-48.