Athletes appear to have a different gut microbiota than the general population, according to new research which explored the impact of training intensity on gut health.
With the aim of helping athletes to improve their health and performance, PhD candidate Bronwen Charlesson, from Edith Cowan University in Australia, set out to better understand how high and low training loads affect athletes’ gut microbiome.
She found that athletes have greater total short chain fatty acid concentrations, alpha diversity, an increased abundance of some bacteria and a lower abundance of others.
Charlesson said that difference in diet could explain the variations in microbiome between athletes and the general population, but she also noted the link with fitness markers, such as oxygen uptake.
Separate to Charlesson’s study, one reason could be that more intense training produces higher levels of blood lactate.
This goes to the gut to be metabolised – which could be one explanation for higher levels of bacteria in the gut.
Charlesson noted: “During low training load times, or periods of rest, athletes are often more relaxed about their diets, in this study we saw no change in total carbohydrate or fibre intake during period of rest but we did observe a decline in the diet quality of food eaten.
“This decline was related to increases in processed fast foods, decreases in fresh fruit and vegetables and a moderate increase in alcohol intake. These changes did impact the composition of the gut microbiome.
“Another observation made during the research was the significant slowing of gut transit times in athletes during low training loads. That slowing of transit time during the low training load appears to also be impacting the gut microbiome for an athlete.”
The authors say that future studies are needed to further the understanding of the link between training intensity, transit time, diet quality, and the composition of gut microbiome in highly trained athletes.
Read more in the Journal of the International Society of Sports Nutrition.