Cardiorespiratory fitness and the gut microbiota

Cardiorespiratory fitness as a predictor of intestinal microbial diversity and distinct metagenomic functions. 

Mehrbod Estaki, Jason Pither et al. Cardiorespiratory fitness as a predictor of intestinal microbial diversity and distinct metagenomic functions. Microbiome (2016) 4:42 DOI 10.1186/s400168-016-0189-7

 

Background: There has been a growing body of science suggesting the importance of the gut microbiota in human health. The influence of exercise on the gut microbes is only beginning to be discovered and studied.


Purpose: To study the impact of cardio-respiratory fitness (VO2peak) on the gut microbiota


Design: Young adults aged 18 - 35 years old underwent a stationary cycling test to assess peak aerobic fitness. Nutritional patterns were also analyzed via a a questionnaire and fecal (poo) samples were also collected so scientists could analyze the microbes. Participants were divided into 3 groups:

1) Low fitness (VO2 peak = 33 ml/kg/min) 
2) Average fitness (41.9 ml/kg/min)
3) Highfitness (54.8 ml/kg/min) 


Results: higher aerobic fitness was significantly correlated with increased microbial "richness" , accounting for approximately 20% of the variation. This is even after accounting for other factors like diet. Also more fit subjects tended to have increased production of butyrate.


What does this mean? 

Butyrate is a short-chain fatty acid. It is produced by the gut bacteria when they ferment components of the food we eat. Short-chain fatty acids are an essential food source for the cells lining our gut.  Gut diversity or "richness" is also important for gut health. 

The finding in this study is relevant because it shows that being aerobically fit may have benefits on our gut health which may then have a positive effect on our overall health. Why? Because the gut microbiota has been shown to be essential for optimal human health. 

 

George Cho