The Gut Microbiome and Indoor Cycling
The relationship between high-intensity exercise and a healthier microbiome.

Can a good hill climb result in healthier digestion? Maybe! Research shows a relationship between the gut microbiome, metabolism and the immune system.
A healthy gut promotes better nutrient absorption, a more effective metabolism and a stronger immune system, among other benefits. Studies have found an additional relationship between physical activity, cardiorespiratory fitness and positive changes in the gut microbiota. Investigators from multiple universities in Italy conducted a 9-week study to determine whether high-intensity interval indoor cycling training over an extended time would improve the gut microbiome.
Researchers recruited 18 healthy, sedentary, male college students. There was not a control group. All subjects participated in the same training and were assessed at the beginning and ending of the 9-week, high-intensity interval cycling program. There were three sessions per week that increased in frequency and duration as participants improved.
Data analyses showed that subjects experienced changes in the abundance and community structure of the gut microbiota. This improved abundance of “good” bacteria and reduced inflammatory bacteria represents a positive change in overall gut health. More research is recommended to better understand how and why microbes play a role in athletic performance and the relationship of physical activity to improvements in gut health.
The research is reported in the Journal of the International Society of Sports Nutrition (2021; 18 [74]).
Shirley Eichenberger-Archer, JD, MA
Shirley Eichenberger-Archer, JD, MA, is an internationally acknowledged integrative health and mindfulness specialist, best-selling author of 16 fitness and wellness books translated into multiple languages and sold worldwide, award-winning health journalist, contributing editor to Fitness Journal, media spokesperson, and IDEA's 2008 Fitness Instructor of the Year. She's a 25-year industry veteran and former health and fitness educator at the Stanford Prevention Research Center, who has served on multiple industry committees and co-authored trade books and manuals for ACE, ACSM and YMCA of the USA. She has appeared on TV worldwide and was a featured trainer on America's Next Top Model.