No effects of a 4-week post-exercise sauna bathing on targeted gut microbiota and intestinal barrier function, and hsCRP in healthy men: a pilot randomized controlled trial

Joanna Karolkiewicz; David C Nieman; Tomasz Cisoń; Joanna Szurkowska; Mirosława Gałęcka; Dariusz Sitkowski; Zbigniew Szygula

doi:10.1186/s13102-022-00497-z

No effects of a 4-week post-exercise sauna bathing on targeted gut microbiota and intestinal barrier function, and hsCRP in healthy men: a pilot randomized controlled trial

BMC Sports Sci Med Rehabil. 2022 Jun 16;14(1):107. doi: 10.1186/s13102-022-00497-z.

Authors

Joanna Karolkiewicz¹, David C Nieman², Tomasz Cisoń³, Joanna Szurkowska⁴, Mirosława Gałęcka⁵, Dariusz Sitkowski⁶, Zbigniew Szygula⁷

Affiliations

¹ Department of Food and Nutrition, Poznan University of Physical Education, Poznań, Poland. karolkiewicz@awf.poznan.pl.
² Department of Biology, Appalachian State University, North Carolina Research Campus, Kannapolis, NC, USA.
³ Department of Physiotherapy, Institute of Physical Education, State University of Applied Sciences in Nowy Sącz, Nowy Sącz, Poland.
⁴ Department of Food and Nutrition, Poznan University of Physical Education, Poznań, Poland.
⁵ Institute of Microecology, Poznań, Poland.
⁶ Department of Physiology, Institute of Sport - National Research Institute PL, Warsaw, Poland.
⁷ Department of Sports Medicine and Human Nutrition, University of Physical Education, Kraków, Poland.

Abstract

Background: 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. This study evaluated the effects of post-exercise sauna bathing in young men undergoing endurance training on gut bacteria inflammation and intestinal barrier function.

Methods: Fifteen (15) 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 min, 3 times per week, on a bicycle ergometer followed by a 30-min 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, zonulin, and secretory immunoglobulin A.

Results: Interaction effects revealed no differences in the pattern of change over time between groups for the abundance of selected gut microbiome bacteria and stool pH, zonulin, sIgA, and hsCRP. Pre- and post-study fecal concentrations of Bifidobacterium spp., Faecalibacterium prausnitzii, and Akkermansia muciniphila were below reference values for these bacteria in both groups.

Conclusions: The combination of 4-weeks exercise followed by passive heat exposure did not have a measurable influence on targeted gut microbiota, intestinal barrier function, and hsCRP levels in young males.

Trial registration: The study was retrospectively registered in the clinical trials registry (Clinicaltrials.gov) under the trial registration number: NCT05277597. Release Date: March 11, 2022.

Keywords: Exercise; Gut microbiota; Intestinal barrier function; Sauna bathing.

Associated data

ClinicalTrials.gov/NCT05277597

Grants and funding

PB.501-1/2018/State University of Applied Sciences in Nowy Sącz