Bodybuilders tend to overeat their daily protein needs. The purpose of a high-protein diet is to support post-workout recovery and skeletal muscle growth; however, its exact impact on gut microbiota still remains under investigation. The aim of this study was to assess the differences in selected gut bacteria (Faecalibacterium prausnitzii, Akkermansia muciniphila, Bifidobacterium spp., and Bacteroides spp.) abundance and fecal pH between the group of amateur bodybuilders and more sedentary control group. In total, 26 young healthy men took part in the study, and their daily nutrients intake was measured using a dietary interview. Real-time PCR was used to assess the stool bacteria abundance. Both groups reported fiber intake within the recommended range, but bodybuilders consumed significantly more protein (33.6% ± 6.5% vs. 22% ± 6.3%) and less fat (27.6% ± 18.9% vs. 36.4% ± 10%) than controls. Study results showed no significant differences in terms of selected intestinal bacteria colony forming unit counts. Significantly higher fecal pH in the bodybuilders’ fecal samples was observed in comparison to the control group 6.9 ± 0.7 vs. 6.2 ± 0.7. Gut microbiota composition similarities could be a result of appropriate fiber intake in both groups.

Background Cyclists often use high-carbohydrate, low-fiber diets to optimize the glycogen stores and to avoid the gastrointestinal distress during both, the trainings and the competitions. The impact of such dietary changes on gut microbiota is not fully known. Methods We assessed the abundances of Faecalibacterium prausnitzii, Akkermansia muciniphila, Bifidobacterium spp., and Bacteroides spp. and the fecal pH in 14 amateur cyclists during the racing season. Eleven healthy men formed the control group. Results Despite significant differences in the diet composition and physical endurance levels of amateur cyclists before the competition season (1st term) and control group (carbohydrates: 52.2% ± 4.9% vs 41.9% ± 6.6%; VO2max: 56.1 ± 6.0 vs 39.7 ± 7.7; p < 0.01; respectively), we did not observe any significant differences in studied gut bacteria abundances or fecal pH between the groups. Although the cyclists’ carbohydrates consumption (2nd term) have increased throughout the season (4.48 g/kg b.w. ± 1.56 vs 5.18 g/kg b.w. ± 1.99; p < 0.05), the studied gut bacteria counts and fecal pH remained unchanged. It seems that the amateur cyclists’ diet with increased carbohydrates intake does not alter the gut microbiota, but further research is needed to assess the potential impact of even higher carbohydrates consumption (over 6 g/kg b.w.).

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.

Background: Body temperature fluctuations induced by acute exercise bouts may also influence the intestinal barrier with related effects on epithelial permeability, immune responses, and release of metabolites produced by the gut microbiota.To evaluate the combined influence of 4-weeks exercise training and post-exercise sauna treatments on gut bacteria and fungi, inflammation, and intestinal barrier function. Methods: Randomized, parallel group design with pre- and post-study measurements.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 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. Group comparisons showed no significant differences for blood and stool sample measurements during the 4-week study.Results: Group comparisons showed no significant differences for blood and stool sample measurements during the 4-week study.Conclusions: The combination of 4-weeks exercise training and post-exercise sauna treatments did not have a measurable influence on targeted gut microbiota, intestinal barrier function, and inflammation biomarkers in young males compared to exercise training alone.