Effect of a 4-week Post-exercise Sauna Bathing on Targeted Gut Microbiota

Effect of a 4-week Post-exercise Sauna Bathing on Targeted Gut Microbiota and Intestinal Barrier Function in Healthy Men: a Randomized Controlled Pilot Trial

Body temperature fluctuations induced by acute exercise bouts may influence the intestinal barrier with related effects on epithelial permeability, immune responses, and release of metabolites produced by the gut microbiota.

Untrained males aged 22±1.5 years were randomly assigned to exercise training (ET) with or without post-exercise sauna treatments (S). Participants in the group ET+S (n=8) exercised 60 minutes, 3 times per week, on a bicycle ergometer followed by a 30-minute dry Finish sauna treatment. The control group (ET, n=7) engaged in the same exercise training program without the sauna treatments. Blood and stool samples were collected before and after the 4-week training program. Blood samples were analysed for the concentration of high-sensitivity C-reactive protein (hsCRP) and complete blood counts. Stool samples were analysed for pH, quantitative and qualitative measures of targeted bacteria and fungi, zonulin, and secretory immunoglobulin A. This study evaluated the effects of post-exercise sauna bathing in young men undergoing endurance training on gut bacteria inflammation and intestinal barrier function. Investigators hypothesized that sauna bathing applied immediately after a physical training session may impact homeostatic control of the gut microbiota and the function of the intestinal barrier.

Inclusion Criteria:

• absence of medical contraindications such as epilepsy,addiction to medicines, alcohol and drugs, cancer, blood clotting disorders,
• no infections in the last 4 weeks prior to the study,
• no injuries in the last 4 weeks prior to the study.

Exclusion Criteria:

• the intake of antibiotics, steroids, oral antifungal agents (except for topical antifungals), antiparasitic agents, pre- and/or probiotics,
• history of travel to tropical countries during the last 4 weeks before the study,
• history of adverse responses to sauna bathing.