Updated: Sep 14, 2021
“If we could give every individual the right amount of nourishment and exercise, not too little and not too much, we would have found the safest way to health.” - Hippocrates
Exercise and the gut…
Did you know that moderate levels of exercise can improve the health of your gut microbiome?
Studies suggest that after only 5 weeks of exercise, the numbers of beneficial butyrate producing microbes increase! Butyrate is a short chain fatty acid produced by gut bugs as a by-product of fibre fermentation. It has numerous beneficial roles including improving gut barrier integrity, regulating immune function and reducing systemic inflammation (it can even cross the blood brain barrier and benefit mood/cognitive function!).
However… high intensity exercise, endurance exercise (particularly in heat) and exercising to failure/exhaustion can be detrimental to the gut microbiome.
High intensity exercise reduces blood flow to the gut wall and can increase intestinal permeability (or 'leaky gut') which can result in symptoms including abdominal pain, diarrhoea and nausea. This disruption to the gut wall can profoundly disrupt the harmony of the gut microbiome. For example, in amateur athletes completing a half-marathon, the gut microbiome was altered to a pro-inflammatory profile post-race. (Ticinesi et al., 2019)
Wanting to exercise but experiencing gut symptoms such as nausea, pain and diarrhoea? Try taking a brisk 30 minute walk daily! An observational study observed that 5-6 hours of brisk walking per week may reduce colon cancer risk by 24%.
Reference: Ticinesi, A., Lauretani, F., Tana, C., Nouvenne, A., Ridolo, E., & Meschi, T. (2019). Exercise and immune system as modulators of intestinal microbiome: Implications for the gut-muscle axis hypothesis. Exercise Immunology Review, 25, 84–95