Avoiding Digestive Issues as a Runner

May 16, 2020

Avoiding Digestive Issues as a Runner

Do you find you suffer from digestive symptoms during training and competition e.g. flatulence, diarrhoea, nausea?

Delve into digestive distress and the risk factors for its development. There are some well-known causes including: reduced blood flow to the digestive tract, anxiety, food sensitivity and much more….

Find out what may be causing YOUR digestive symptoms and learn how they could be alleviated. Avoiding digestive issues as a runner will help ensure you can attain and maintain peak running performance.

LISTEN HERE Episode 3: Avoiding Digestive Issues as a Runner



Discover the risk factors for digestive distress in runners.


Why does reduced blood flow in the GI tract during running lead to digestive distress.


Fertility and stress connections regarding endurance sports


The impact of pre race anxiety on digestive function.


How mechanical risks (bouncing effects of being a runner) may impact on digestive distress.


A deeper look into the effects of mechanical effects (bouncing) or running on our digestive system.


A look at the foods and drinks commonly thought to trigger digestive distress for runners


What runners may do to minimise the potential effects of particular foods on digestive distress.


The impact of common “over the counter” medications on digestion.


More risk factors, such as intensive exercise or endurance running and dehydration,


The importance of resolving day to day digestive issues and looking at common gastrointestinal symptoms.


When the body is under stress from running, blood flow is preferentially diverted from digestion to working muscles and heart… after all the heart is a large muscle. Blood flow to intestines may be reduced by up to 80%.

For female runners it is important to mention that blood is also diverted away from the reproductive system (stress response). There is often mention of the fact that stress may affect fertility and exercise may be contributing to this stress. So for any woman trying to become pregnant, it would be important to bear this in mind. So avoiding digestive issues as a runner may have a positive impact in other areas of your health.


  • Introduce small amounts of protein/CHO pre-training and build up
  • Minimise or remove fat/fibre pre/during training
  • Limit carbohydrate intake during training (30g and 60g/h) – practice during training to work out how much you need. Practice with different CHO food sources to find out which causes no or least digestive side effects
  • Ensure any drinks/gels contain less than 10% carbohydrate concentration – remember most contain only 6% – but check!
  • Remain hydrated – before and after as well as during. Guidelines suggest drinking every mile. Important to find out what works for you
  • Train in the environment in which you will be competing
  • Remove or limit medications/supplements pre training
  • Limit caffeine intake pre/during training

A final thought is that having an optimal digestive system is foundational and if it’s not, then our advice would be to see a nutritional therapist or other health professional to resolve issues. Running and racing and all that entails will exacerbate symptoms you may experience on training runs and race days.

Related Episodes:

Hydration and Running Performance

Nutrient Timing for Running Performance

Energy Bars, Gels and Protein Powders

Related Resources:

Do Runners Need Protein Powder

Optimal Hydration for Runners


The suggestions we make during this episode are for guidance and advice only, and are not a substitute for medical advice or treatment. If you have any concerns regarding your health, please contact your healthcare professional for advice as soon as possible.

Remember we are available to support you if required contact us at hello@ runnershealthhub.com

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