Gut Microbiota and Serum Metabolome in Elite Cross-Country Skiers: A Controlled Study

Abstract

Exercise has been shown to affect gut the microbiome and metabolic health, with athletes typically displaying a higher microbial diversity. However, research on the gut microbiota and systemic metabolism in elite athletes remains scarce. In this study, we compared the gut microbiota profiles and serum metabolome of national team cross-country skiers at the end of an exhausting training and competitive season to those of normally physically-active controls. The gut microbiota were analyzed using 16S rRNA amplicon sequencing. Serum metabolites were analyzed using nuclear magnetic resonance. Phylogenetic diversity and the abundance of several mucin-degrading gut microbial taxa, including Akkermansia, were lower in the athletes. The athletes had a healthier serum lipid profile than the controls, which was only partly explained by body mass index. Butyricicoccus associated positively with HDL cholesterol, HDL2 cholesterol and HDL particle size. The Ruminococcus torques group was less abundant in the athlete group and positively associated with total cholesterol and VLDL and LDL particles. We found the healthier lipid profile of elite athletes to co-occur with known health-beneficial gut microbes. Further studies should elucidate these links and whether athletes are prone to mucin depletion related microbial changes during the competitive season.

Physical Activity, Sedentary Behavior and Microbiome: A Systematic Review and Meta-analysis

“…inactive participants 36,38,63,66,68–71,78,84,85,39,41,42,44–46,48,59 ( Table 2 ). Sixteen studies found significant differences in microbial diversity 47,49,62,74–76,79,80,51,52,54–58,61 and 13 in the abundance of specific microbial taxa 47,52,78,79,104,53,55–58,74–76 between athletes vs . non-athletes, professional vs .…”

“…Most of the studies analyzed the gut microbiome, with the exception of ten which collected saliva, oral, oropharyngeal, muscle, blood or vaginal samples 36,43,52,64,80,86,88,102,113,116 ( Table 2 ). Concerning the detection method, 78 studies conducted the 16S rRNA gene sequencing approach to characterize the microbiome 23,36,45–48,51– 53,55,56,58,37,59–64,66–69,38,70–79,39,80–87,90,91,40,92–95,97–100,102,103,41,104,105,107–113,115,42,116,118–121,123–125,43,44 , 16 performed metagenomics analyses 23,49,101,106,114,115,117,122,50,54,57,60,65,89,95,96 and two studies focused on meta-transcriptomics (i.e., microbial RNA-sequencing) 50,88 . Twenty-one studies did not report dietary data for all the participants 36,39,102,104,106,111,113,115–117,119,121,74,123,76,79,80,…”

“…Concerning the detection method, 78 studies conducted the 16S rRNA gene sequencing approach to characterize the microbiome 23,36,45–48,51– 53,55,56,58,37,59–64,66–69,38,70–79,39,80–87,90,91,40,92–95,97–100,102,103,41,104,105,107–113,115,42,116,118–121,123–125,43,44 , 16 performed metagenomics analyses 23,49,101,106,114,115,117,122,50,54,57,60,65,89,95,96 and two studies focused on meta-transcriptomics (i.e., microbial RNA-sequencing) 50,88 . Twenty-one studies did not report dietary data for all the participants 36,39,102,104,106,111,113,115–117,119,121,74,123,76,79,80,86,88,98,99 . One study performed a control of diet (each participants received the same kind of food) during the PA intervention 87 .…”

“…Of the 50 cross-sectional studies, 8 were eligible (based on availability of microbiome diversity data and healthy participants) for the first meta-analysis comparing groups of high and low PA levels in non-athletes 44,66,69,70,78,81,83,85 , and 11 were included in the second meta-analysis comparing athletes vs . non-athletes 47,49,104,51,56,60,74,76,78,79,81 . Of the 32 intervention studies, 7 were selected for the third meta-analysis, to evaluate the chronic effects of PA on microbiome alpha-diversity 96,97,99,109,112,119,124 .…”

“…Additionally, four studies reported SB data expressed as time per sedentary breaks/bouts or screen time 48,64,70,73 . Twenty-two cross-sectional studies recruited athletes from different sports such as rugby, athletics or football, among others 47,49,58,60–62,74–79,50,80,104,51–57 . Six studies analyzed the effects of a marathon, footrace or rowing race on microbiome 23,87,89,90,92,93 , three reported the effect of a single bout of PA (i.e., no sport competition) on microbiome 86,88,91 and 32 conducted a long-term PA intervention ranged from two weeks 121 to thirty-four weeks 115 , mostly consisting of aerobic training 94,95,113,115,119– 121,97,98,103,105,107,109,111,112 or a combination of aerobic and resistance training 96,99,116–118,122–125,100–102,104,106,108,110,114 .…”