Exercise and Your Gut Will Thank You

Exercise tied to more diverse good bacteria in the digestive system

/ Author:  / Reviewed by: Joseph V. Madia, MD Beth Bolt, RPh

(RxWiki News) Bacteria aren't just foreign invaders that make us sick. We also hold healthy bacteria within our bodies. Hosting a diverse collection of this good bacteria in the gut may depend on more than diet.

In a recent study, researchers looked at fecal and blood samples from professional athletes in a training camp and compared them to the samples of men in a control group. The researchers also studied the participants' eating habits and exercise levels.

These researchers found that the athletes had a wider range of good bacteria in their digestive systems than the men in the control group, especially those who were overweight.

The authors of this study suggested that vigorous exercise could play a significant role in keeping the digestive system healthy.

"Exercise regularly."

Professor Fergus Shanahan, of the Department of Medicine at University College Cork, led this study.

Many different types of bacteria live in the digestive system and aid in digestion. According to the authors of the study, disturbances in the gut's bacteria can increase the risk of obesity and some diseases.

This study examined how exercise affects the gut's population of bacteria.

The researchers recruited 40 professional rugby athletes to participate in the study. The participants were male, an average of 29 years old, and had an average body mass index of 29.1. 

Two control (comparison) groups with 23 participants each were recruited. The first control group had BMIs of 25 or lower (typically considered healthy weight). The second group had BMIs greater than 28 (overweight).

The researchers collected fecal and blood samples from the participants.

Nutritionists interviewed each participant, and the participants filled out a food frequency questionnaire that asked about food consumption over the past four weeks.

The control group participants also completed a physical activity questionnaire. The athletes were enrolled in a rigorous training program.

The researchers also used levels of plasma creatine kinase (CK), a marker of extreme exercise, to compare exercise levels between the participants.

The researchers found that levels of CK were higher in the group of athletes than in the two control groups. The athletes also had lower levels of inflammation.

Using the fecal samples, the researchers found that the athletes had a more diverse network of bacteria in their digestive systems than the two control groups. 

Overall, the athletes had 22 different phyla, or groups of bacteria types, in their fecal samples.

The control group with lower BMIs had 11 different phyla, and the high BMI group had nine phyla.

The researchers also found that protein accounted for 22 percent of the total caloric intake among the athletes.

The lower BMI group got 16 percent of their calories from protein, and the high BMI group ate 15 percent protein.

The authors of this study concluded that exercise was tied to more diverse gut bacteria, which could promote improved gut health.

Additionally, gut bacteria diversity was associated with high protein intake and higher levels of CK.

The authors suggested that both diet and exercise are important factors that influence gut bacteria diversity.

This study was published in Gut on June 9.

The research was funded by the Teagasc Walsh Fellowship and a Science Foundation Ireland award. One of the authors was funded by the Teagasc Walsh fellowships.

Review Date: 
June 9, 2014
Last Updated:
June 11, 2014