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Cited by 389Gut microbiota and healthProbiotics and Fermented FoodsGastrointestinal motility and disorders

The athletic gut microbiota

Open access
Mohr, Alex E., Jäger, Ralf, Carpenter, Katie C., Kerksick, Chad M., Purpura, Martin, Townsend, Jeremy R., West, Nicholas P., Black, Katherine +16 more·2020·Journal of the International Society of Sports Nutrition
DOI 10.1186/s12970-020-00353-wPMC PMC7218537
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Abstract

The microorganisms in the gastrointestinal tract play a significant role in nutrient uptake, vitamin synthesis, energy harvest, inflammatory modulation, and host immune response, collectively contributing to human health. Important factors such as age, birth method, antibiotic use, and diet have been established as formative factors that shape the gut microbiota. Yet, less described is the role that exercise plays, particularly how associated factors and stressors, such as sport/exercise-specific diet, environment, and their interactions, may influence the gut microbiota. In particular, high-level athletes offer remarkable physiology and metabolism (including muscular strength/power, aerobic capacity, energy expenditure, and heat production) compared to sedentary individuals, and provide unique insight in gut microbiota research. In addition, the gut microbiota with its ability to harvest energy, modulate the immune system, and influence gastrointestinal health, likely plays an important role in athlete health, wellbeing, and sports performance. Therefore, understanding the mechanisms in which the gut microbiota could play in the role of influencing athletic performance is of considerable interest to athletes who work to improve their results in competition as well as reduce recovery time during training. Ultimately this research is expected to extend beyond athletics as understanding optimal fitness has applications for overall health and wellness in larger communities. Therefore, the purpose of this narrative review is to summarize current knowledge of the athletic gut microbiota and the factors that shape it. Exercise, associated dietary factors, and the athletic classification promote a more "health-associated" gut microbiota. Such features include a higher abundance of health-promoting bacterial species, increased microbial diversity, functional metabolic capacity, and microbial-associated metabolites, stimulation of bacterial abundance that can modulate mucosal immunity, and improved gastrointestinal barrier function.

AI snapshot

Written from the paper’s full text.

TL;DR

This narrative review summarizes evidence that exercise, athletic diet, and athlete classification are associated with a more “health-associated” gut microbiota, including greater diversity, health-promoting taxa, short-chain fatty acids, and functional metabolic pathways. It also emphasizes that causality and long-term effects remain unclear because most evidence is cross-sectional, methodologically heterogeneous, and confounded by diet.

Key findings

  • Athletes generally show higher gut microbiota diversity and health-associated taxa than controls. In professional rugby players (n = 40) vs matched controls (n = 46), athletes had higher diversity representing 22 distinct phyla; *Akkermansia* was higher in athletes and low-BMI controls than high-BMI controls. In female cohorts, athletes had the highest alpha diversity, while anorexia nervosa and obese participants had lower richness.
  • Exercise and fitness correlate with microbial diversity and short-chain fatty acids. VO2peak explained ~20% of variation in gut bacterial alpha diversity in one study and ~22% of variance in the Firmicutes/Bacteroidetes ratio in another; athletes had enriched fecal SCFAs (acetate, propionate, butyrate) and higher TMAO. In cyclists, *Prevotella* was higher in those training > 11 h/week; *Akkermansia* was present in 30/33 cyclists, with 7 having relative abundances > 2%.
  • Acute and chronic exercise can shift specific taxa and metabolites. Post-marathon *Veillonella* increased; *Veillonella atypica* inoculation improved mouse time to exhaustion by 13%. In prediabetic men, exercise responders had −42.70% fasting insulin and −49.60% HOMA-IR, with ~30% responding poorly; baseline microbiome predicted response. Ultra-endurance rowing increased alpha diversity by day 17 and persisted at 3 months.
  • Diet interacts strongly: protein intake correlated positively with diversity in rugby athletes but negatively with Shannon diversity in distance runners (R = −0.63, P = 0.01); fat intake negatively correlated with *Bifidobacteria* in bodybuilders (R = −0.52, P = 0.05). High-protein supplementation increased Bacteroidetes and decreased *Roseburia*, *Blautia*, and *B. longum*; ketogenic LCHF increased *Bacteroides*/*Dorea* and decreased *Faecalibacterium*.

Methods

  • Narrative review summarizing current knowledge of the athletic gut microbiota and the factors that shape it; not a systematic review or meta-analysis.
  • Synthesizes animal and human studies, including cross-sectional comparisons, longitudinal exercise interventions, randomized controlled trials, and metabolomic/metagenomic studies; Tables 1 and 2 list included article characteristics.
  • Main analysis is narrative synthesis of compositional and functional microbiome findings, with attention to exercise, diet, and athlete classification.

Limitations

  • Stated: current evidence is limited; much research is cross-sectional and has relied on 16S rRNA sequencing; methodological variation across studies makes comparisons difficult; many studies may be underpowered and fail to control for confounders such as diet, sex, ethnicity, GI problems, and antibiotics; deep discussion of each study’s methods was not possible.
  • Stated: exercise and diet are difficult to separate, and athletes’ distinct diets may confound exercise-specific effects.
  • Evident: as a narrative review, it does not report a systematic search strategy, risk-of-bias assessment, or quantitative pooling; included studies are heterogeneous and often small, limiting causal inference.

Model-written summary. Check it against the paper before relying on it.

Integrity signals

Registry

Crossref · 10.1186/s12970-020-00353-w

Cites

245 of 245 references verified0 citation errors · 0 not checkable

Statistics

Nothing to recompute.

Claims the paper makes

0 of 366 cited sources checked · 0 supported · 0 flagged

  • Findingreasoning

    Among exercise studies in animals there was little agreement regarding what taxa are influenced by chronic exercise.

    “Amongst the exercise studies in animals there was little agreement regarding what taxa are influenced by chronic exercise.”
    Quote in the paperNot a substantial claim
  • Findingnone given

    Few human studies have examined the effect of energy intake and energy expenditure on the gut microbiota.

    “In terms of human research there are few studies that have examined the effect of energy intake and energy expenditure on the gut microbiota.”
    Quote in the paperSubstantial claim
  • Findingnone given

    Little is known about the effects of energy-reduced diets in athletes seeking to healthfully reduce bodyweight and/or improve body composition.

    “little is known on the effects of energy reduced diets in athletes looking to healthfully reduce bodyweight and/or improve body composition.”
    Quote in the paperNot a substantial claim
  • Findingnone given

    No study in athletes has addressed RED-S in relation to the gut microbiota.

    “To date, no study in athletes has addressed RED-S in relation to the gut microbiota.”
    Quote in the paperNot a substantial claim
  • Findingcitation

    Even less is known about the gut microbiota in undernutrition compared to high-energy intake and obesity.

    “In contrast to high-energy intake and obesity, even less is known about the gut microbiota in undernutrition [142].”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [142] Krajmalnik-Brown R, 2012, Nutr Clin Pract source

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    Findingnone given

    The majority of human research on energy intake/expenditure and gut microbiota has been conducted in relation to obesity, weight loss, and malnourishment in children.

    “The majority of this research has been conducted in relation to the study of obesity, weight loss, and malnourishment in children.”
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  • Probably not a substantial claim: may not pass S3 (load-bearing), S4 (based).

    Findingnone given

    Primer selection and hypervariable regions of 16S rRNA (V1-V9) influence the observed microbial community.

    “Primer selection and hypervariable regions of 16S rRNA (i.e., V1-V9) influence the observed microbial community.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S4 (based). May combine two claims.

    Findingnone given

    Several studies report less stringent inclusion/exclusion criteria and did not fully account for or control confounding variables.

    “Several studies report less stringent inclusion/exclusion criteria and did not fully account/control for confounding variables.”
    Quote in the paperNot a substantial claim

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    Findingnone given

    Feces is the only sample material used in the analyses of the gut microbiota from the studies included in this review.

    “feces is the only sample material used in the analyses of the gut microbiota from the studies included in this review.”
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    Findingnone given

    Several reports did not provide adequate detail in regard to sample transportation and storage.

    “several reports did not provide adequate detail in regard to sample transportation and storage.”
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    Findingnone given

    Several studies in the present review did not provide adequate detail on sample collection and processing.

    “Several studies in the present review did not provide adequate detail on sample collection and processing.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S4 (based).

    Findingnone given

    The effects of high-protein consumption without concurrent high-fat on gut bacteria are not well studied.

    “the effects of high-protein consumption (without concurrent high-fat) on gut bacteria are not well studied but of increasing importance given the current popularity of high-protein diets, especially in athletes.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S4 (based).

    Findingnone given

    Current microbiota sequencing methods rely heavily on 16S rRNA amplicon-based methodology, which detects up to genus level with minimal capability for species-level detection.

    “Current microbiota sequencing methods rely heavily on 16S rRNA amplicon-based methodology which detects up to genus level with minimal capability for species-level detection.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    Important factors such as age, birth method or delivery route, antibiotic use, and diet shape the gut microbiota.

    “Important factors such as age, birth method, antibiotic use, and diet have been established as formative factors that shape the gut microbiota.”
    • Also stated in: § Introduction · plain
      “Important factors such as age, birth delivery route, antibiotic use, and diet can shape the gut microbiota [7–10].”
    Quote in the paperNot a substantial claim0 of 4 sources checked
    • cites [7] Yatsunenko T, 2012, Nature. source

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    • cites [8] Dudek-Wicher RK, 2018, Prz Gastroenterol

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    • cites [9] Flint HJ, 2015, Proc Nutr Soc source

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    • cites [10] Wampach L, 2018, Nat Commun source

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  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Premisecitation

    The human gut microbiota contains thousands of bacterial taxa, archaea, eukaryotic microbes, viruses, more than three million genes, and an enormous metabolic capacity.

    “The human gut microbiota contains thousands of different bacterial taxa as well as various archaea, eukaryotic microbes and viruses, more than three million genes, and harbors an enormous metabolic capacity [1, 2].”
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    • cites [1] Human Microbiome Project C, 2012, Nature. source

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    • cites [2] Qin J, 2010, Nature. source

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    Study design and conductreasoning

    Confounding factors including training history, level of physical fitness, training environment, and dietary intake can affect study outcomes substantially and make detecting differences due to exercise or athletic regimens on the gut microbiota difficult to ascertain.

    “Moreover, confounding factors including training history, level of physical fitness, training environment, and dietary intake all have the potential to affect study outcomes substantially, and make detecting differences due to exercise/athletic regimens on the gut microbiota difficult to ascertain.”
    Quote in the paperSubstantial claim

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    Premisecitation

    Athlete type did not differ regarding gut microbiota alpha and beta diversity but was significantly associated with the relative abundance of several bacteria.

    “While athlete type did not differ regarding gut microbiota alpha and beta diversity, it was significantly associated with the relative abundance of several bacteria.”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [11] Jang LG, 2019, J Int Soc Sports Nutr source

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    Premisecitation

    Total fat mass, serum lipids, C-reactive protein, depression scales, and smoking status were negatively associated with microbiota diversity.

    “Interestingly, total fat mass, serum lipids, C-reactive protein, depression scales, and smoking status were negatively associated (R2 = − 0.012 to − 0.256, P < 0.05) with microbiota diversity.”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [57] Morkl S, 2017, Int J Eat Disord source

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    Interpretationcitation

    From the limited evidence, athletes harbor an increased abundance of functional pathways within the microbiome that are exploited by the host for potential health benefits, as well as carbohydrate degradation and secondary metabolite metabolism compared to control groups.

    “From the limited evidence, it appears that athletes harbor an increased abundance of functional pathways within the microbiome that are exploited by the host for potential health benefits, as well as carbohydrate degradation and secondary metabolite metabolism compared to control groups [60].”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [60] Flint HJ, 2012, Gut Microbes source

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    Premisecitation

    Exercise type was associated with athlete diet patterns: bodybuilders had a high-protein, high-fat, low-carbohydrate, and low-dietary fiber diet; distance runners had a low-carbohydrate and low-dietary fiber diet.

    “Exercise type was associated with athlete diet patterns (i.e., bodybuilders: high-protein, high-fat, and low-carbohydrate/dietary fiber diet; distance runners: low-carbohydrate and low-dietary fiber diet).”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [11] Jang LG, 2019, J Int Soc Sports Nutr source

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    Interpretationcitation

    The microbiota has an indirect influence on various indices of exercise performance, recovery, and patterns of illness, such as signaling through myokines and other cytokines, modulating activation of the hypothalamic-pituitary-adrenal axis, and affecting performance-associated metabolic pathways.

    “The microbiota has an indirect influence on various indices of exercise performance, recovery, and patterns of illness, such as signaling through myokines and other cytokines, modulating activation of the hypothalamic–pituitary–adrenal axis, and affecting performance-associated metabolic pathways [13, 16–18].”
    Quote in the paperSubstantial claim0 of 4 sources checked
    • cites [13] Barton W, 2018, Gut.

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    • cites [16] Scheiman J, 2019, Nat Med source

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    • cites [17] Cerda B, 2016, Front Physiol source

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    • cites [18] Petersen LM, 2017, Microbiome. source

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    Premisecitation

    In females, microbiota diversity was markedly lower in anorexia nervosa patients and obese participants compared to other groups, while athletes showed the highest alpha diversity (species richness).

    “Microbiota diversity was markedly lower in anorexia nervosa patients and obese participants compared to other groups, while athletes showed the highest alpha diversity (species richness).”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [57] Morkl S, 2017, Int J Eat Disord source

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    Interpretationnone given

    Physical activity appears to promote a health-associated microbial community and increased metabolic functional potential.

    “Physical activity has been an area of growing interest in gut microbiota research and appears to promote a health-associated microbial community and increased metabolic functional potential.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Interpretationreasoning

    Exercise, associated dietary factors, and athletic classification promote a more health-associated gut microbiota.

    “Exercise, associated dietary factors, and the athletic classification promote a more “health-associated” gut microbiota.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Interpretationcitation

    The observed differences in microbiome and metabolome-related patterns across athlete classifications occurred despite no significant variation in dietary intakes, suggesting that variations in training loads and competition requirements contributed to these patterns.

    “However, these differences were observed despite no significant variation in dietary intakes across athletes from different classifications; suggesting that variations in training loads and competition requirements contributed to these microbiome and metabolome-related patterns.”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [58] O'Donovan CM, 2020, J Sci Med Sport source

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    Premisecitation

    Athletes participating in sports with a high dynamic component were the most distinct compositionally, while athletes participating in sports with both a high dynamic and static component were the most functionally distinct.

    “Athletes participating in sports with a high dynamic component were the most distinct compositionally (greater differences in proportions of species; see Table 1), while athletes participating in sports with both a high dynamic and static component were the most functionally distinct (greater differences in functional potential).”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [58] O'Donovan CM, 2020, J Sci Med Sport source

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    Premisecitation

    At the genus level, Faecalibacterium, Sutterella, Clostridium, Haemophilus, and Eisenbergiella were the highest, while Bifidobacterium and Parasutterella were the lowest in bodybuilders.

    “For instance, at the genus level, Faecalibacterium, Sutterella, Clostridium, Haemophilus, and Eisenbergiella were the highest, while Bifidobacterium and Parasutterella were the lowest in bodybuilders.”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [11] Jang LG, 2019, J Int Soc Sports Nutr source

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    Premisecitation

    Current research reports a higher abundance of health-promoting bacterial species and increased microbial diversity in athletes.

    “Current research reports a higher abundance of health-promoting bacterial species and increased microbial diversity in athletes [13, 18, 19].”
    Quote in the paperNot a substantial claim0 of 3 sources checked
    • cites [13] Barton W, 2018, Gut.

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    • cites [18] Petersen LM, 2017, Microbiome. source

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    • cites [19] Clarke SF, 2014, Gut. source

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    Premisecitation

    In sedentary and physically active premenopausal women, physical exercise was not related to differences in microbiota diversity or richness, but sedentary parameters correlated negatively with microbiota richness.

    “Physical exercise was not related to differences in the microbiota diversity or richness (the total number of OTUs or species recorded); however, sedentary parameters (i.e., sedentary time and breaks) correlated negatively with microbiota richness.”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [56] Bressa C, 2017, PLoS One source

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    Premisecitation

    Akkermansia was present in 30 out of 33 cyclists, with seven cyclists having relative abundances greater than 2%.

    “In addition, Akkermansia was present in 30 out of 33 cyclists, with seven cyclists having relative abundances > 2% of this microbe in their metagenomic community.”
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    • cites [18] Petersen LM, 2017, Microbiome. source

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    Premisecitation

    Fecal and urine derived metabolites varied between classification including increased lactate in urine in sports with a static component and creatinine in feces in sports with a high dynamic and low static component.

    “Fecal and urine derived metabolites also varied between classification including increased lactate (urine) in sports with a static component and creatinine (feces) in sports with a high dynamic and low static component.”
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    • cites [58] O'Donovan CM, 2020, J Sci Med Sport source

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    Premisecitation

    A. muciniphilia is a mucin-degrading bacterium that resides in the nutrient-rich mucus layer of the gut and appears to be associated with positive metabolic function.

    “A. muciniphilia is a mucin-degrading bacterium that resides in the nutrient-rich mucus layer of the gut that appears to be associated with positive metabolic function [59].”
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    • cites [59] Dao MC, 2016, Gut. source

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    Premisecitation

    Health-related effects of butyrate are associated with anti-inflammatory properties, direct feeding of colonocytes, and an impact on satiety.

    “Briefly, the health-related effects of butyrate are associated with anti-inflammatory properties, direct feeding of colonocytes, and an impact on satiety [64].”
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    • cites [64] den Besten G, 2013, J Lipid Res source

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    Premisecitation

    Exercised mice presented a greater abundance of Firmicutes species and lower Bacteroides/Prevotella genera compared with sedentary mice.

    “Lambert et al. [75] described that exercised mice presented a greater abundance of Firmicutes species and lower Bacteroides/Prevotella genera compared with sedentary mice.”
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    • cites [75] Lambert JE, 2015, Appl Physiol Nutr Metab source

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    Premisecitation

    In comparison to sedentary control, mice with running wheel exercise had higher phylum Firmicutes but fewer phyla Tenericutes and Bacteroidetes, which attenuated changes in gut microbiota induced by oral exposure to polychlorinated biphenyls.

    “In particular, Choi et al. [73] reported that, in comparison to a sedentary control, mice with running wheel exercise had higher phylum Firmicutes but fewer phyla Tenericutes and Bacteroidetes, which attenuated changes in gut microbiota induced by oral exposure to the environmental toxin, polychlorinated biphenyls.”
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    • cites [73] Choi JJ, 2013, Environ Health Perspect source

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    Premisecitation

    The Firmicutes/Bacteroidetes ratio is not always the same between studies and may be an oversimplification of phylum-level patterns in relation to host health.

    “However, this is not always the same between studies [83, 84] and may be an oversimplification of phylum-level patterns in relation to host health.”
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    • cites [83] Walters WA, 2014, FEBS Lett source

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    • cites [84] Finucane MM, 2014, PLoS One source

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    Premisecitation

    Butyrate, along with propionate and acetate, provides ~10% of daily caloric requirements in humans who consume high (~60 g/day) amounts of dietary fiber.

    “Notably, butyrate, along with propionate and acetate, provides ~ 10% of the daily caloric requirements in humans who consume high (~ 60 g/day) amounts of dietary fiber [64].”
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    • cites [64] den Besten G, 2013, J Lipid Res source

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    Premisecitation

    Regular running exercise in rats is related to an increase in butyrate-producing bacteria and an increase of butyrate concentration.

    “Matsumoto et al. [72] reported that regular running exercise in rats was related to an increase in butyrate-producing bacteria in the microbiota composition along with an increase of butyrate concentration.”
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    • cites [72] Matsumoto M, 2008, Biosci Biotechnol Biochem source

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    Premisecitation

    Mechanisms by which specific members of the microbiota, such as Firmicutes and Bacteroidetes, can affect human phenotypes remain to be fully elucidated.

    “Further, mechanisms by which specific members of the microbiota, such as Firmicutes and Bacteroidetes, can affect human phenotypes remain to be fully elucidated [85].”
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    • cites [85] Johnson EL, 2017, J Mol Med (Berl) source

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    Premisecitation

    Exercise increased Bacteroidetes while it decreased Firmicutes in mice, implying that exercise plays an important role in prevention of diet-induced obesity producing a microbial composition similar to lean mice.

    “In contrast, Evans et al. [74] concluded that exercise increased Bacteroidetes, while it decreased Firmicutes in mice, implying that exercise plays an important role in prevention of diet-induced obesity producing a microbial composition similar to lean mice.”
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    • cites [74] Evans CC, 2014, PLoS One

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    Premisecitation

    One leading theory on the pathogenesis of obesity emphasizes a close link between the metabolic and immune systems via the gut microbiota.

    “One leading theory on the pathogenesis of obesity emphasizes a close link between the metabolic and immune systems via the gut microbiota [68].”
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    • cites [68] Cox AJ, 2015, Lancet Diabetes Endocrinol source

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    Premisecitation

    Exercised mice have bacteria related to Faecalibacterium prausnitzii which may protect the digestive tract by producing butyrate and lowering oxygen tension in the lumen by a flavin/thiol electron shuttle.

    “Campbell et al. [88] asserted that exercised mice have bacteria related to Faecalibacterium prausnitzii which may protect the digestive tract by producing butyrate and lowering the oxygen tension in the lumen by a flavin/thiol electron shuttle.”
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    • cites [88] Campbell SC, 2016, PLoS One source

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    Premisecitation

    The athlete gut microbiome may possess a functional capacity primed for tissue repair and a greater ability to harness energy from the diet with increased capacity for carbohydrate metabolism, cell structure, and nucleotide biosynthesis.

    “Barton et al. [13] speculated that the athlete gut microbiome may possess a functional capacity primed for tissue repair and a greater ability to harness energy from the diet with increased capacity for carbohydrate metabolism, cell structure, and nucleotide biosynthesis.”
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    • cites [13] Barton W, 2018, Gut.

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    Premisecitation

    Increased intestinal permeability from high-fat/high-sugar diets allows bacterial LPS from the gut microbiota to translocate into the systemic circulation, resulting in systemic endotoxemia.

    “This body of work suggests that increased intestinal permeability from high-fat / high sugar diets allows bacterial lipopolysaccharide (LPS), an outer membrane component of gram-negative bacteria linked with induction of inflammation, from the gut microbiota to translocate into the systemic circulation, resulting in systemic endotoxemia.”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [68] Cox AJ, 2015, Lancet Diabetes Endocrinol source

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  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Premisecitation

    A. muciniphilia has also been found to be enriched in mice fed a ketogenic diet, exhibiting gut-brain functions including conferring seizure protection in two preclinical models for refractory epilepsy.

    “A. muciniphilia has also been found to be enriched in mice fed a ketogenic diet, exhibiting gut-brain functions including conferring seizure protection in two preclinical models for refractory epilepsy [66].”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [66] Olson CA, 2018, Cell. source

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    Premisecitation

    A. muciniphilia levels are decreased in obese and type 2 diabetic mice, and treatment with these bacteria reversed high-fat diet-induced metabolic disorders, including fat mass gain, metabolic endotoxemia, adipose tissue inflammation, and insulin resistance.

    “A. muciniphilia levels are decreased in obese and type 2 diabetic mice, and treatment with these bacteria reversed high-fat diet-induced metabolic disorders, including fat mass gain, metabolic endotoxemia, adipose tissue inflammation, and insulin resistance [65].”
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    • cites [65] Everard A, 2013, Proc Natl Acad Sci U S A source

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    Premisecitation

    While the role of A. muciniphila is less certain in humans, it is depleted in individuals with several metabolic and inflammatory disorders.

    “While the role of A. muciniphila is less certain in humans, it is depleted in individuals with several metabolic and inflammatory disorders.”
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    • cites [59] Dao MC, 2016, Gut. source

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  • Classified as probably not a substantial claim.

    Interpretationreasoning

    Being physically active is another important factor in the relationship between the microbiota and host metabolism.

    “It appears that being physically active is another important factor in the relationship between the microbiota and host metabolism.”
    Quote in the paperSubstantial claim

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    Premisecitation

    Aerobic capacity was inversely associated with Eubacterium rectale-Clostridium coccoides but not with other bacteria.

    “Aerobic capacity was inversely associated with Eubacterium rectale-Clostridium coccoides but not with other bacteria.”
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    • cites [94] Yang Y, 2017, Nutrients. source

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    Premisecitation

    The relative abundance of Veillonella increased after the marathon and was the most differentially abundant microbial feature between pre- and post-exercise states.

    “The relative abundance of the bacterial genus Veillonella increased after the marathon and was the most differentially abundant microbial feature between the pre- and post-exercise states.”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [16] Scheiman J, 2019, Nat Med source

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    Premisecitation

    Participants with low VO2max had lower Bacteroides, but higher Eubacterium rectale-Clostridium coccoides than the high VO2max group.

    “Participants with low VO2max had lower Bacteroides, but higher Eubacterium rectale-Clostridium coccoides than the high VO2max group.”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [94] Yang Y, 2017, Nutrients. source

      Not checked in the free run.

  • May combine two claims.

    Premisecitation

    Half-marathon running reduced the abundance of fecal Ezakiella, Romboutsia, and Actinobacillus, but increased the abundance of Coprococcus and Ruminococcus bicirculans.

    “At the genus level, half-marathon running reduced the abundance of fecal Ezakiella, Romboutsia, and Actinobacillus, but increased the abundance of Coprococcus and Ruminococcus bicirculans.”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [20] Zhou Y, 2014, Genome Biol source

      Not checked in the free run.

  • May combine two claims.

    Premisecitation

    Coriobacteriaceae is involved in metabolism of bile salts and steroid hormones as well as activation of dietary polyphenols in the human gut.

    “Coriobacteriaceae (phylum Actinobacteria) is involved in metabolism of bile salts and steroid hormones as well as activation of dietary polyphenols in the human gut [95].”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [95] Clavel T, 2014

      Not checked in the free run.

  • May combine two claims.

    Premisecitation

    Bacterial abundance of Clostridiaceae and Bacteroidaceae families and Ruminoccocus genus were negatively associated with blood lactate levels in exercised animals, whereas a positive association was reported for Oscillospira genus.

    “The bacterial abundance of Clostridiaceae and Bacteroidaceae families and Ruminoccocus genus were negatively associated with blood lactate levels in exercised animals, whereas a positive association was reported for Oscillospira genus [86].”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [86] Petriz BA, 2014, BMC Genomics source

      Not checked in the free run.

  • May combine two claims.

    Interpretationreasoning

    The inverse relationship between VO2peak and LPS biosynthesis pathways implies a beneficial consequence of increased physical activity which may result in decreased LPS biosynthesis.

    “The inverse relationship between VO2peak and LPS biosynthesis pathways implies a beneficial consequence of increased physical activity which may result in decreased LPS biosynthesis.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Premisecitation

    VO2peak was inversely correlated with LPS biosynthesis and LPS biosynthesis proteins, which were elevated among less fit participants.

    “VO2peak was inversely correlated with LPS biosynthesis and LPS biosynthesis proteins which were elevated among less fit participants.”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [14] Estaki M, 2016, Microbiome. source

      Not checked in the free run.

  • May combine two claims.

    Interpretationreasoning

    Coriobacteriaceae was correlated positively with 15 metabolites, indicating that metabolism of Coriobacteriaceae may be a potential mechanism underlying the role of exercise in preventing disease and improving health outcomes.

    “Coriobacteriaceae was correlated positively with 15 metabolites, indicating that metabolism of Coriobacteriaceae may be a potential mechanism underlying the role of exercise in preventing disease and improving health outcomes.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Premisecitation

    In amateur runners before and after a half-marathon, alpha diversity showed few differences, but abundances of certain microbiota members differed before and after running.

    “According to the alpha diversity analysis, there were few differences in diversity, nevertheless, abundances of certain microbiota members showed differences before and after running.”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [20] Zhou Y, 2014, Genome Biol source

      Not checked in the free run.

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Interpretationcitation

    It was unclear if the higher diversity in rugby players was due to exercise, a high-protein diet, a combination of these two factors, or other factors.

    “However, it was unclear if this effect was due to exercise, a high-protein diet, a combination of these two factors, or other factors [19].”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [19] Clarke SF, 2014, Gut. source

      Not checked in the free run.

  • May combine two claims.

    Premisecitation

    ~20% of the variation in gut bacterial alpha diversity could be explained by VO2peak alone, and VO2peak was the only variable that contributed significantly to increased alpha diversity.

    “Further, ~ 20% of the variation in gut bacterial alpha diversity could be explained by VO2peak alone; in fact, VO2peak stood as the only variable that contributed significantly to increased alpha diversity.”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [14] Estaki M, 2016, Microbiome. source

      Not checked in the free run.

  • May combine two claims.

    Premisecitation

    Alterations to the microbiota exerted by exercise in rats following a high-fat diet were different to rats on a normal diet, and alterations in diabetic mice were different to their control counterparts.

    “Alterations to the microbiota exerted by exercise in rats following a high-fat diet were different to rats on a normal diet [89], as well as the alterations produced in diabetic mice were different to their control counterparts [75].”
    Quote in the paperSubstantial claim0 of 2 sources checked
    • cites [89] Kang SS, 2014, Mol Neurodegener source

      Not checked in the free run.

    • cites [75] Lambert JE, 2015, Appl Physiol Nutr Metab source

      Not checked in the free run.

  • May combine two claims.

    Interpretationreasoning

    Modulation of the microbiota by chronic exercise depends not only on the physiological state of the individual, but also on the diet.

    “Collectively, these findings indicate that modulation of the microbiota by chronic exercise depends not only on the physiological state of the individual, but also on the diet.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Interpretationcitation

    V. atypica improved run time via its metabolic conversion of exercise-induced lactate into propionate, identifying a natural, microbiome-encoded enzymatic process that enhances athletic performance.

    “Taken together, these experiments revealed that V. atypica improved run time via its metabolic conversion of exercise-induced lactate into propionate, thereby identifying a natural, microbiome-encoded enzymatic process that enhances athletic performance.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Interpretationreasoning

    This research took an important step from correlative to causal function, implicating athlete microbiomes for broader human health and performance applications.

    “While performed in animal model, this research is notable as it took an important step from correlative to causal function, implicating athlete microbiomes for broader human health and performance applications.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Interpretationown data

    The genus Veillonella is enriched in athletes after exercise and the metabolic pathway that Veillonella species utilize for lactate metabolism is also enriched.

    “It seems that the genus Veillonella is enriched in athletes after exercise and the metabolic pathway that Veillonella species utilize for lactate metabolism is also enriched.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Premisecitation

    In the Liu study, responders showed a decrease in fasting insulin and HOMA-IR values of −42.70% and −49.60%, respectively.

    “Those that did respond showed a remarkable decrease in fasting insulin and Homeostatic Model Assessment of Insulin Resistance index values (− 42.70% and − 49.60%, respectively).”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [106] Liu Y, 2019, Cell Metab source

      Not checked in the free run.

  • May combine two claims.

    Interpretationcitation

    Gut microbiota composition is linked to exercise status and exercise-induced changes may be temporary and require continual stimulus.

    “This study supports the notion that gut microbiota composition is linked to exercise status and that exercised-induced changes may be temporary and require continual stimulus [100].”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [100] Hawley JA, 2019, Nat Rev Endocrinol source

      Not checked in the free run.

  • May combine two claims.

    Premisecitation

    In mice transplanted with microbiota from responders, glycemic control and insulin sensitivity substantially improved, whereas mice colonized with microbiota from non-responders showed no change.

    “A substantial improvement in mice gavaged with microbiota from responders was mimicked in glycemic control and insulin sensitivity, in contrast to the lack of change in mice colonized with microbiota from non-responders.”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [106] Liu Y, 2019, Cell Metab source

      Not checked in the free run.

  • The quote only partly states this claim.

    Premisecitation

    In healthy women, the relative abundance of intestinal Bacteroides increased in subjects who completed a 12-week aerobic exercise intervention.

    “The relative abundance of intestinal Bacteroides increased in subjects that completed aerobic exercise.”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [103] Morita E, 2019, Nutrients. source

      Not checked in the free run.

  • May combine two claims.

    Premisecitation

    In the Taniguchi trial, the relative abundance of Clostridioides difficile decreased and Oscillospira increased during exercise compared to the control period.

    “the relative abundance of Clostridioides difficile decreased, whereas that of Oscillospira increased during exercise compared to the control period”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [101] Taniguchi H, 2018, Phys Rep

      Not checked in the free run.

  • May combine two claims.

    Premisecitation

    In the Liu study, there was clear segregation in compositional and functional changes between exercise responders and non-responders, accompanied by distinct alterations in microbial metabolites.

    “there was a clear segregation in compositional and functional changes between exercise responders and non-responders, accompanied by distinct alterations in microbial metabolites.”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [106] Liu Y, 2019, Cell Metab source

      Not checked in the free run.

  • May combine two claims.

    Premisecitation

    Exercise-induced modulations of the gut microbiota and SCFA were strongly associated with changes in body composition in lean participants and VO2max in obese participants, independent of diet.

    “Exercise-induced modulations of the gut microbiota and SCFA were strongly associated with changes in body composition in lean participants and VO2max in obese participants, independent of diet.”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [98] Allen JM, 2018, Med Sci Sports Exerc source

      Not checked in the free run.

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    Microbial short-chain fatty acids appear to influence blood pressure by interacting with host SCFA receptors.

    “It appears microbial SCFAs influence blood pressure by interacting with host SCFA receptors [102].”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [102] Pluznick JL, 2017, Curr Hypertens Rep source

      Not checked in the free run.

  • May combine two claims.

    Premisecitation

    In the Kern study, beta diversity changed in all exercise groups compared to control, with participants in the vigorous intensity group showing decreased heterogeneity.

    “Beta diversity changed in all exercise groups compared to control, with participants in the vigorous intensity group showing decreased heterogeneity.”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [108] Kern T, 2019, Int J Obes source

      Not checked in the free run.

  • May combine two claims.

    Interpretationreasoning

    The observed shifts in metabolic capacity of the gut microbiota may be transient and likely dependent on repeated exercise stimuli.

    “This connection is also supported by the observed shifts in metabolic capacity of the gut microbiota which may be transient and likely dependent on repeated exercise stimuli.”
    Quote in the paperSubstantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Premisecitation

    Lower levels of Bacteroides are associated with higher prevalence of obesity and metabolic syndrome, and Bacteroides species may help suppress metabolic dysfunction.

    “It is widely accepted that lower levels of Bacteroides are associated with the higher prevalence of obesity and metabolic syndrome and that Bacteroides species may help in suppressing metabolic dysfunction [79, 104].”
    Quote in the paperNot a substantial claim0 of 2 sources checked
    • cites [79] Ley RE, 2006, Nature. source

      Not checked in the free run.

    • cites [104] Santacruz A, 2010, Br J Nutr source

      Not checked in the free run.

  • May combine two claims.

    Interpretationreasoning

    Higher levels of lactic acid in athletes' GI tract favor the growth of Veillonella and these bacteria may in turn produce a compound that could aid performance.

    “Higher levels of lactic acid in athletes’ GI tract favor the growth of this genus and these bacteria may in turn produce a compound that could aid performance.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Premisecitation

    In a preclinical crossover trial, Veillonella-inoculated mice had a 13% improvement in time to exhaustion running tests and significant reductions in inflammatory cytokines post exercise compared to control.

    “In a pre-clinical crossover trial, Veillonella inoculated mice had a 13% improvement in time to exhaustion running tests as well as significant reductions in inflammatory cytokines post exercise compared to control.”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [16] Scheiman J, 2019, Nat Med source

      Not checked in the free run.

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Interpretationreasoning

    The increased relative abundance of Bacteroides after the 12-week exercise intervention may be due to its ability to shift substrates compared to other taxa that more reproducibly decline with a high-fat diet.

    “therefore, the increased relative abundance observed after the 12-week exercise intervention may be due to its ability to shift substrates compared to other taxa that more reproducibly decline with a high-fat diet (i.e., Bifidobacteria).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [105] Abenavoli L, 2019, Nutrients. source

      Not checked in the free run.

  • May combine two claims.

    Premisecitation

    Aerobic exercise also increases fecal SCFA concentration, which can decrease pH in the colonic lumen.

    “Aerobic exercise also increases fecal SCFA concentration which can decrease pH in the colonic lumen [125].”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [125] Walker AW, 2005, Appl Environ Microbiol source

      Not checked in the free run.

  • May combine two claims.

    Premisecitation

    Increased intestinal permeability ensues, thought to be driven by phosphorylation of several tight junction proteins.

    “increased intestinal permeability ensues, thought to be driven by the phosphorylation of several tight junction proteins [129].”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [129] Zuhl M, 2014, Br J Sports Med source

      Not checked in the free run.

  • May combine two claims.

    Interpretationreasoning

    These results highlight the importance of intestinal substrate uptake on the whole body, and changes especially in glucose uptake might have a positive effect on the gut microbiota.

    “These results highlight the importance of intestinal substrate uptake on the whole-body and changes, especially in glucose uptake, might have a positive effect on the gut microbiota.”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [109] Motiani KK, 2019, Med Sci Sports Exerc source

      Not checked in the free run.

  • May combine two claims.

    Premisecitation

    Longer colonic transit time is associated with decreased gut microbiota diversity, paralleled by an increase in pH during transit from the proximal to the distal colon.

    “longer colonic transit time is associated with decreased gut microbiota diversity, which is paralleled by an increase in pH during transit from the proximal to the distal colon [116, 117].”
    Quote in the paperNot a substantial claim0 of 2 sources checked
    • cites [116] Tottey W, 2017, J Neurogastroenterol Motil source

      Not checked in the free run.

    • cites [117] Abbas A, 2014, J Gastroenterol Hepatol Res

      Not checked in the free run.

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Interpretationreasoning

    Many microbial characteristics may be a result of 'form fits function', as communities in the gut are shaped by available resources determined by the physiology of their host.

    “many of these microbial characteristics may be a result of ‘form fits function’, as communities in the gut are shaped by available resources, as determined by the physiology of their host.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Interpretationreasoning

    Physically active individuals are more likely to be exposed to their environmental biosphere and follow an overall healthy lifestyle and consequently harbor a richer microbiota.

    “physically active individuals are more likely to be exposed to their environmental biosphere (e.g., time spent outdoors) and follow an overall healthy lifestyle and, consequently, harbor a richer microbiota.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Premisecitation

    Clostridium plays an important role in whole-body immune responses, while Blautia purportedly increases the release of proinflammatory cytokines.

    “Clostridium plays an important role in whole-body immune responses, while Blautia purportedly increases the release of proinflammatory cytokines [111].”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [111] Tuovinen E, 2013, Anaerobe. source

      Not checked in the free run.

  • May combine two claims.

    Premisecitation

    In that acute exercise study, Bacteroidetes increased and the Firmicutes/Bacteroidetes ratio decreased.

    “Bacteroidetes increased and the Firmicutes/Bacteroidetes ratio decreased.”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [109] Motiani KK, 2019, Med Sci Sports Exerc source

      Not checked in the free run.

  • May combine two claims.

    Premisecitation

    Intestinal ischemia may result, particularly in the setting of dehydration, manifesting as abdominal cramps, diarrhea, or occasionally bloody diarrhea.

    “Intestinal ischemia may result, particularly in the setting of dehydration, manifesting as abdominal cramps, diarrhea, or occasionally bloody diarrhea [127].”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [127] de Oliveira EP, 2009, Curr Opin Clin Nutr Metab Care source

      Not checked in the free run.

  • Probably not a substantial claim: may not pass S3 (load-bearing), S4 (based).

    Interpretationreasoning

    These and other potential adaptive mechanisms, such as a change in gut pH, may create an environmental setting that allows for richer community diversity and metabolic functions.

    “These and other potential adaptive mechanisms, such as a change in gut pH, may create an environmental setting that allows for richer community diversity and metabolic functions.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing), S4 (based).

    Interpretationnone given

    Metabolites that are by-products of exercise and circulate throughout the body, such as lactate, may filter through the gut and serve as an energy source for certain bacterial taxa such as Veillonella.

    “metabolites that are a by-product of exercise and circulate throughout the body (e.g., lactate) may filter through the gut and serve as an energy source for certain bacterial taxa (e.g., Veillonella).”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Premisecitation

    In the Keohane study, the increase in alpha diversity occurred independent of any change in cardiorespiratory fitness, with VO2max similar pre- and post-race.

    “This increase occurred independent of any change in cardiorespiratory fitness, with VO2max similar pre- and post-race.”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [99] Keohane DM, 2019, J Sci Med Sport source

      Not checked in the free run.

  • May combine two claims.

    Premisenone given

    Prolonged intestinal hypo-perfusion impairs mucosal homeostasis and causes enterocyte injury.

    “Prolonged intestinal hypo-perfusion impairs mucosal homeostasis and causes enterocyte injury.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Premisecitation

    Changes in GI transit time have been reported to affect the pH within the colonic lumen, which could lead to alterations in the composition of the gut microbiota.

    “Changes in GI transit time have been reported to affect the pH within the colonic lumen which could lead to alterations in the composition of the gut microbiota.”
    Quote in the paperNot a substantial claim0 of 2 sources checked
    • cites [116] Tottey W, 2017, J Neurogastroenterol Motil source

      Not checked in the free run.

    • cites [117] Abbas A, 2014, J Gastroenterol Hepatol Res

      Not checked in the free run.

  • May combine two claims.

    Premisecitation

    Colonic glucose concentrations associated positively with Bacteroidetes and inversely with Firmicutes phylum, the Firmicutes/Bacteroidetes ratio, and Blautia genus.

    “colonic glucose concentrations associated positively with Bacteroidetes and inversely with Firmicutes phylum, the Firmicutes/Bacteroidetes ratio, and Blautia genus.”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [109] Motiani KK, 2019, Med Sci Sports Exerc source

      Not checked in the free run.

  • May combine two claims.

    Premisecitation

    Changes in essential amino acid availability influence hematopoiesis, which in turn may increase oxygen carrying capacity and cardiorespiratory fitness.

    “Changes in essential amino acid availability influence hematopoiesis, which in turn may increase oxygen carrying capacity and cardiorespiratory fitness [112].”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [112] Ohtani M, 2006, J Nutr source

      Not checked in the free run.

  • Probably not a substantial claim: may not pass S4 (based). May combine two claims.

    Premisereasoning

    Athletes often consume a diet that differs from the general population, with implications for the composition of the gut microbiome.

    “Athletes often consume a diet that differs from the general population with implications on the composition of the gut microbiome.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Premisecitation

    Athletes consume higher energy diets compared to sedentary individuals and are often encouraged to consume a diet high in carbohydrate and protein and lower in fat.

    “athletes consume higher energy diets compared to sedentary individuals and are often encouraged to consume a diet high in carbohydrate and protein and lower in fat [140].”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [140] Kerksick CM, 2018, J Int Soc Sports Nutr source

      Not checked in the free run.

  • May combine two claims.

    Premisecitation

    Germ-free mice are inefficient at processing food, but when colonized with conventional mouse gut microbiota they gain weight by increasing their energy stores.

    “Gnotobiotic mice are inefficient at processing food, yet when colonized with conventional mouse gut biota they gain weight by increasing their energy stores [152].”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [152] Turnbaugh PJ, 2006, Nature. source

      Not checked in the free run.

  • May combine two claims.

    Interpretationnone given

    Nearly all studies included in this review have shown positive correlations between gut taxa and exercise; overall exercise appears to enrich microbiota diversity, stimulate proliferation of bacteria that can modulate mucosal immunity, improve barrier functions, and functional pathways capable of producing substances such as butyrate and propionate that can increase performance and health.

    “Nearly all studies included in this review have shown positive correlations between gut taxa and exercise. Overall exercise appears to enrich microbiota diversity, stimulate the proliferation of bacteria which can modulate mucosal immunity, improve barrier functions, and functional pathways capable of producing substances (e.g., butyrate and propionate) that can increase performance and health.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Premisecitation

    In mice, the gut microbiota affects energy balance by influencing the efficiency of calorie harvest from the diet and how harvested energy is used and stored.

    “Studies of lean and obese mice indicate that the gut microbiota affects energy balance by influencing the efficiency of calorie harvest from the diet and how this harvested energy is used and stored.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Interpretationreasoning

    Based on the current body of research, exercise appears to enrich microbiota diversity, stimulate proliferation of bacteria that can modulate mucosal immunity, improve barrier functions, and stimulate bacteria and functional pathways capable of producing substances that protect against gastrointestinal disorders and improve performance, such as SCFAs.

    “exercise appears to enrich microbiota diversity, stimulate the proliferation of bacteria which can modulate mucosal immunity, improve barrier functions, and stimulate bacteria and functional pathways capable of producing substances that protect against gastrointestinal disorders and improve performance (i.e., SCFAs).”
    Quote in the paperSubstantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing), S4 (based). May combine two claims.

    Interpretationnone given

    Exercise-induced changes in gut microbiota may not occur in a similar fashion across individuals and may depend on baseline characteristics of both the microbiota and host.

    “Although these changes may not occur in a similar fashion across individuals and may also depend on baseline characteristics of both the microbiota and host.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing), S4 (based). May combine two claims.

    Interpretationnone given

    Exercise-induced shifts in metabolic capacity of the gut microbiota may be transient and likely dependent on repeated exercise stimuli.

    “Exercise induced shifts in metabolic capacity of the gut microbiota may be transient and likely dependent on repeated exercise stimuli.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    During training and competition, fiber intake may be reduced to avoid potential GI issues including gas and distension.

    “During training and competition, fiber intake may be reduced to avoid potential GI issues including gas and distension [141].”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [141] Tiller NB, 2019, J Int Soc Sports Nutr source

      Not checked in the free run.

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    Medication and diet are principal environmental factors that influence gut microbiota composition according to large-cohort studies.

    “Medication and diet are principal environmental factors that influence gut microbiota composition according to large-cohort studies [135, 136].”
    Quote in the paperNot a substantial claim0 of 2 sources checked
    • cites [135] Falony G, 2016, Science. source

      Not checked in the free run.

    • cites [136] Zhernakova A, 2016, Science. source

      Not checked in the free run.

  • May combine two claims.

    Premisecitation

    The gut microbiota contributes to host digestive efficiency and thus plays a role in energy balance.

    “Strong evidence exists to support the role for the gut microbiota in energy balance by contributing to host digestive efficiency [151].”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [151] Scheithauer TP, 2016, Mol Metab source

      Not checked in the free run.

  • May combine two claims.

    Premisecitation

    Diet is an established modulator of gut microbiota composition, with significant alterations reported within 24 h of a dietary change.

    “Diet is an established modulator of gut microbiota composition, with significant alterations reported within 24 h of a dietary change [134].”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [134] David LA, 2014, Nature. source

      Not checked in the free run.

  • Probably not a substantial claim: may not pass S3 (load-bearing), S4 (based).

    Interpretationnone given

    Exercise may promote a rich bacterial community-induced shift in SCFA-producing taxa by providing selective advantage for colonization of certain microbes, including A. muciniphila and Veillonella.

    “Exercise may promote a rich bacterial community-induced shift in SCFA-producing taxa by providing selective advantage for the colonization of certain microbes, including A. muciniphila and Veillonella.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Premisecitation

    In humans, when comparing obese and lean individuals, both gut microbiota diversity and the ratio of Bacteroidetes to Firmicutes are decreased in obese individuals.

    “Generally, when comparing obese and lean individuals, both the diversity of the gut microbiota and the ratio of Bacteroidetes to Firmicutes is decreased in obese individuals [145].”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [145] Rosenbaum M, 2015, Trends Endocrinol Metab source

      Not checked in the free run.

  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Premisecitation

    The gut microbiota can synthesize de novo amino acids and is involved in the utilization and catabolism of several amino acids from alimentary and endogenous proteins; these amino acids can serve as precursors for synthesis of other metabolites including SCFAs.

    “the gut microbiota can also synthesize de novo amino acids and is involved in the utilization and catabolism of several amino acids originating from both alimentary and endogenous proteins. These amino acids can serve as precursors for the synthesis of other metabolites produced by the microbiota including SCFAs [139].”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [139] Neis EP, 2015, Nutrients. source

      Not checked in the free run.

  • Probably not a substantial claim: may not pass S4 (based).

    Interpretationnone given

    Changes in host phenotype may be more dependent on the metabolic capacity and metabolites of the microbiota than on strictly microbial composition.

    “Changes in host phenotype may be more dependent on the metabolic capacity and metabolites of the microbiota, instead of strictly microbial composition.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Premisecitation

    The gut microbiota plays an important role in energy extraction and can be influenced by the composition of the diet and the amount of energy entering this environment.

    “the gut microbiota plays an important role in energy extraction and, in turn, can be influenced by the composition of the diet and the amount of energy entering this environment [145].”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [145] Rosenbaum M, 2015, Trends Endocrinol Metab source

      Not checked in the free run.

  • May combine two claims.

    Premisecitation

    In rats, a high-energy dense diet rapidly alters the gut microbiota, increasing the Firmicutes/Bacteroidetes ratio and pro-inflammatory Proteobacteria proliferation compared to a low-energy diet.

    “rats fed a high-energy dense diet rapidly altered their gut microbiota with increases in Firmicutes/Bacteroidetes ratio and in pro-inflammatory Proteobacteria proliferation compared to those consuming a low-energy diet [154].”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [154] Vaughn AC, 2017, Acta Neurobiol Exp source

      Not checked in the free run.

  • Probably not a substantial claim: may not pass S4 (based).

    Interpretationnone given

    Changes in the gut microbiota exerted by exercise seem to depend on the physiological state of the individual.

    “Changes in the gut microbiota exerted by exercise seem to depend on the physiological state of the individual.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing), S4 (based).

    Interpretationnone given

    Gene content/diversity in the gut may be a better predictor of physiological states compared to species richness.

    “Gene content/diversity in the gut may be a better predictor of physiological states compared to species richness.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing), S4 (based).

    Interpretationnone given

    Prolonged excessive exercise has a deleterious influence on intestinal function, including increased intestinal permeability.

    “Prolonged excessive exercise has a deleterious influence on intestinal function, including increased intestinal permeability.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S4 (based). May combine two claims.

    Interpretationnone given

    Higher cardiorespiratory fitness, as measured by VO2peak, appears to be correlated positively with increases in microbial diversity and metabolic function, and increases in the SCFA butyrate.

    “Higher cardiorespiratory fitness (as measured by VO2peak) appears to be correlated positively with increases in microbial diversity and metabolic function, and increases in the SCFA butyrate.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Premisecitation

    Moderate endurance exercise in mice has been associated with lesser intestinal permeability, preservation of mucous thickness, lower rates of bacterial translocation, and up-regulated anti-microbial protein production and gene expression in small intestinal tissue.

    “Moderate endurance exercise in mice has been associated with a lesser degree of intestinal permeability, preservation of mucous thickness, and lower rates of bacterial translocation along with up-regulated anti-microbial protein production and gene expression in small intestinal tissue (α-defensin, β-defensin, Reg IIIb and Reg IIIc) [131].”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [131] Luo B, 2014, Brain Behav Immun source

      Not checked in the free run.

  • May combine two claims.

    Premisecitation

    In an in-patient, medically supervised weight gain study in anorexic individuals, microbial richness increased, but perturbations in intestinal microbiota and SCFA profiles, as well as several gastrointestinal symptoms, did not recover during the in-patient stay.

    “During an in-patient, medically supervised weight gain study in anorexic individuals, microbial richness increased, however perturbations in intestinal microbiota and SCFA profiles, in addition to several gastrointestinal symptoms, did not recover during the subject’s in-patient stay [169].”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [169] Mack I, 2016, Sci Rep source

      Not checked in the free run.

  • May combine two claims.

    Premisecitation

    In five male volunteers consuming high intakes of animal protein, fecal sulfide production is related to meat intake; hydrogen sulfide is associated with ulcerative colitis.

    “a study of five male volunteers consuming high intakes of animal protein showed that fecal sulfide production is related to meat intake [176]; notably, hydrogen sulfide is a compound associated with ulcerative colitis [177].”
    Quote in the paperNot a substantial claim0 of 2 sources checked
    • cites [176] Magee EA, 2000, Am J Clin Nutr source

      Not checked in the free run.

    • cites [177] Rowan FE, 2009, Br J Surg source

      Not checked in the free run.

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    Reduced abundance of Firmicutes after bariatric surgery has been reported.

    “Changes such as reduced abundance of Firmicutes post-surgery have been reported [162].”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [162] Rejeh N, 2008, Int Nurs Rev source

      Not checked in the free run.

  • May combine two claims.

    Premisecitation

    Several studies of anorexia nervosa patients have reported decreased abundances of the butyrate-producing Roseburia, reduced butyrate levels, and lower microbial diversity and taxa abundance compared to healthy controls.

    “Several studies of anorexia nervosa patients have reported decreased abundances of the butyrate producing Roseburia in combination with reduced butyrate levels and lower microbial diversity and taxa abundance compared to healthy controls [168–170].”
    Quote in the paperNot a substantial claim0 of 3 sources checked
    • cites [168] Borgo F, 2017, PLoS One source

      Not checked in the free run.

    • cites [169] Mack I, 2016, Sci Rep source

      Not checked in the free run.

    • cites [170] Kleiman SC, 2015, Psychosom Med source

      Not checked in the free run.

  • Probably not a substantial claim: may not pass S4 (based).

    Premisenone given

    Different dietary patterns affecting macronutrient consumption can alter the composition of what enters the large intestine, where there is the greatest density of gut microbes.

    “Different dietary patterns affecting macronutrient consumption can alter the composition of what enters the large intestine where there is the greatest density of gut microbes.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    Relative Energy Deficiency in Sports (RED-S) syndrome is present in many athletic disciplines as a result of insufficient energy availability due to insufficient caloric intake and/or excessive energy expenditure.

    “Relative Energy Deficiency in Sports (RED-S) syndrome is present in many athletic disciplines as a result of insufficient energy availability due to insufficient caloric intake and/or excessive energy expenditure [158].”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [158] Mountjoy M, 2014, Br J Sports Med source

      Not checked in the free run.

  • May combine two claims.

    Premisecitation

    The Bacteroides/Prevotella ratio was negatively correlated with body weight, BMI, and body fat mass, but this correlation was highly dependent on total calorie intake.

    “While this ratio was negatively correlated with body weight, BMI, and body fat mass, the correlation was highly dependent on total calorie intake.”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [163] Furet JP, 2010, Diabetes. source

      Not checked in the free run.

  • May combine two claims.

    Premisecitation

    The 'immaturity' of the gut microbiota was greater in more severely malnourished children, with probable physiologic, metabolic, and immunologic consequences.

    “This ‘immaturity’ was greater in those more severely malnourished with probable physiologic, metabolic, and immunologic consequences [165].”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [165] Subramanian S, 2014, Nature. source

      Not checked in the free run.

  • May combine two claims.

    Premisecitation

    Calorie restriction, primarily in animals, can improve the composition and associated metabolism of the gut microbiota, including increasing the relative abundances of probiotic and butyrate-producing microbes and increasing SCFA biosynthesis.

    “Calorie restriction, primarily in animals, can improve the composition and associated metabolism of the gut microbiota, including increasing the relative abundances of probiotic and butyrate-producing microbes [159] and increasing SCFA biosynthesis [160].”
    Quote in the paperNot a substantial claim0 of 2 sources checked
    • cites [159] Zheng X, 2018, Front Med source

      Not checked in the free run.

    • cites [160] Tanca A, 2018, Sci Rep source

      Not checked in the free run.

  • May combine two claims.

    Premisecitation

    Treatment with purified sialylated bovine milk oligosaccharides produced microbiota-dependent growth promotion in mice colonized with fecal microbiota from a growth-stunted Malawian infant, including lean body mass gain, changed bone morphology, and altered liver, muscle and brain metabolism.

    “Treatment with the milk oligosaccharides produced microbiota-dependent growth promotion, including lean body mass gain, changed bone morphology, and altered liver, muscle and brain metabolism.”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [166] Charbonneau MR, 2016, Cell. source

      Not checked in the free run.

  • Probably not a substantial claim: may not pass S2 (checkable), S4 (based).

    Interpretationreasoning

    It is difficult, if not impossible, to investigate the impact of total energy consumption on gut microbiota composition without considering dietary variability such as major dietary macronutrient classes.

    “it is difficult (if not impossible) to solely investigate the impact of total energy consumption on the composition of the gut microbiota without considering dietary variability such as the major dietary macronutrient classes.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Premisecitation

    The enterotype categorization has been criticized as an oversimplification that obscures potentially important microbial variation and may not be appropriate for the athletic population.

    “This categorization has been criticized as an oversimplification, obscuring potentially important microbial variation, and may not be appropriate for the athletic population [180, 181].”
    Quote in the paperNot a substantial claim0 of 2 sources checked
    • cites [180] Costea PI, 2018, Nat Microbiol source

      Not checked in the free run.

    • cites [181] Knights D, 2014, Cell Host Microbe source

      Not checked in the free run.

  • May combine two claims.

    Interpretationcitation

    Preclinical models indicate a causal, microbiota-dependent relationship between nutrition and growth promotion, which may have implications for younger athletes.

    “These preclinical models indicate a causal, microbiota-dependent relationship between nutrition and growth promotion which may have implications for younger athletes.”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [166] Charbonneau MR, 2016, Cell. source

      Not checked in the free run.

    • Rests on an assumption: Findings from animal models (mice, piglets) can be extrapolated to humans, including athletes.

  • Probably not a substantial claim: may not pass S4 (based).

    Interpretationreasoning

    The composition of what enters the large intestine has a tremendous impact on the human body's ability to extract and utilize energy from the diet.

    “This has a tremendous impact on the human body’s ability to extract and utilize energy from the diet.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S2 (checkable), S4 (based).

    Interpretationnone given

    Energy balance is an overlooked factor in relation to the athletic gut microbiota.

    “Overall, energy balance is an overlooked factor in relation to the athletic gut microbiota.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Premisecitation

    The Bacteroides/Prevotella ratio increased within 3 months after bariatric surgery and remained stable thereafter.

    “Furet and colleagues [163] reported that the Bacteroides/Prevotella ratio increased within 3 months after surgery and remained stable thereafter.”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [163] Furet JP, 2010, Diabetes. source

      Not checked in the free run.

  • May combine two claims.

    Interpretationreasoning

    The gut microbiota is responsive to energy balance (degree of overfeeding) as well as actual adiposity.

    “This finding suggests that the microbiota is responsive to energy balance (degree of overfeeding) as well as actual adiposity.”
    Quote in the paperSubstantial claim

  • Classified as probably not a substantial claim.

    Premisecitation

    Disrupted microbiota development impairs healthy bone and muscle growth during infancy.

    “This has led to the proposal that disrupted microbiota development impairs healthy bone and muscle growth during infancy [166].”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [166] Charbonneau MR, 2016, Cell. source

      Not checked in the free run.

  • May combine two claims.

    Premisecitation

    In lean and obese humans, a higher caloric load (3400 vs 2400 kcal/day) was positively correlated with the relative abundance of Firmicutes species and negatively correlated with the relative abundance of Bacteroidetes species.

    “The higher caloric load was positively correlated with the relative abundance of Firmicutes species and negatively correlated with the relative abundance of Bacteroidetes species in both lean and obese humans.”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [157] Jumpertz R, 2011, Am J Clin Nutr source

      Not checked in the free run.

  • May combine two claims.

    Premisecitation

    RED-S occurs in both males and females and poses a significant health risk.

    “Occurring in both males and females, RED-S possesses a significant health risk.”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [158] Mountjoy M, 2014, Br J Sports Med source

      Not checked in the free run.

  • May combine two claims.

    Premisecitation

    When dietary protein is increased, Bacteroides spp. are highly associated with animal proteins, whereas Prevotella spp. are highly associated with increased intakes of plant proteins.

    “Changes to the gut microbiota have also been documented when dietary protein is increased: Bacteroides spp. are highly associated with animal proteins, whereas Prevotella spp. are highly associated with increased intakes of plant proteins [172].”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [172] Wu GD, 2011, Science. source

      Not checked in the free run.

  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Premisecitation

    Excessive protein intake or an unsuitable ratio of protein to protein-fermenting bacteria could potentially produce adverse effects on health.

    “Ma et al. [178] suggested that excessive protein intake or an unsuitable ratio of protein to protein-fermenting bacteria, could potentially produce adverse effects on health.”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [178] Ma N, 2017, Curr Protein Pept Sci

      Not checked in the free run.

  • May combine two claims.

    Premisecitation

    In humans, consuming a high-fat/protein diet for 5 days caused a rapid shift in gut microbial community composition and increased populations of Alistipes, Bilophila, and Bacteroides, thought to result from increased bile secretion.

    “David et al. [134] showed a rapid shift in gut microbial community composition and increased populations of Alistipes, Bilophila, and Bacteroides after consuming a high-fat/protein diet for 5 days and these changes were thought to be a result of increased bile secretion.”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [134] David LA, 2014, Nature. source

      Not checked in the free run.

  • Classified as probably not a substantial claim.

    Interpretationreasoning

    The inconsistency between these results and Clarke et al. may relate to the nutritional status of the athletes.

    “The inconsistency of these results compared to Clarke et al. [19] may relate to the nutritional status of the athletes.”
    Quote in the paperSubstantial claim0 of 2 sources checked
    • cites [19] Clarke SF, 2014, Gut. source

      Not checked in the free run.

    • cites [11] Jang LG, 2019, J Int Soc Sports Nutr source

      Not checked in the free run.

  • May combine two claims.

    Premisecitation

    In cross-country runners, 10 weeks of daily protein supplementation (10 g whey isolate and 10 g beef hydrolysate) decreased SCFA-producing bacteria and increased bacteria with proteolytic activity in the microbiota, without affecting SCFAs, ammonia, or fecal pH.

    “In cross-country runners, the effect of 10 weeks of protein supplementation (10 g whey isolate and 10 g beef hydrolysate per day) consumed daily decreased SCFA-producing bacteria while increasing bacteria with proteolytic activity in the microbiota without affecting SCFAs, ammonia, or fecal pH of endurance athletes [196].”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [196] Moreno-Perez D, 2018, Double-Blind Pilot Study Nutrients

      Not checked in the free run.

  • May combine two claims.

    Premisecitation

    Protein supplementation increased the abundance of the Bacteroidetes phylum and decreased the presence of health-related taxa including Roseburia, Blautia, and B. longum.

    “Specifically, protein supplementation increased the abundance of the Bacteroidetes phylum and decreased the presence of health-related taxa including Roseburia, Blautia, and B. longum.”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [196] Moreno-Perez D, 2018, Double-Blind Pilot Study Nutrients

      Not checked in the free run.

  • May combine two claims.

    Premisecitation

    BCAAs do not enhance exercise performance, but they may reduce central fatigue and attenuate muscle damage during prolonged exercise.

    “While there is strong evidence showing that BCAAs do not enhance exercise performance [192, 193], they may reduce central fatigue [194] and attenuate muscle damage during prolonged exercise [195].”
    Quote in the paperSubstantial claim0 of 4 sources checked
    • cites [192] Negro M, 2008, J Sports Med Phys Fitness

      Not checked in the free run.

    • cites [193] van Hall G, 1995, J Physiol source

      Not checked in the free run.

    • cites [194] Newsholme EA, 2006, J Nutr source

      Not checked in the free run.

    • cites [195] Greer BK, 2007, Int J Sport Nutr Exerc Metab source

      Not checked in the free run.

  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Premisecitation

    Saccharolytic organisms such as Ruminococcaceae and Lachnospiraceae persist in fibrolytic gut communities and are considered an important component of a healthy gut microbiota, while their depletion has been observed in inflammatory bowel disease patients.

    “These saccharolytic organisms persist in fibrolytic gut communities and are considered an important component of a healthy gut microbiota, while their depletion has been observed in inflammatory bowel disease patients [189, 190].”
    Quote in the paperNot a substantial claim0 of 2 sources checked
    • cites [189] Frank DN, 2007, Proc Natl Acad Sci U S A source

      Not checked in the free run.

    • cites [190] Fujimoto T, 2013, J Gastroenterol Hepatol source

      Not checked in the free run.

  • May combine two claims.

    Premisecitation

    These microbial features positively correlate with athletes' levels of physical activity and the quantity of dietary protein consumed.

    “These microbial features not only positively correlate with the athletes’ levels of physical activity, but also the quantity of dietary protein consumed.”
    Quote in the paperSubstantial claim0 of 2 sources checked
    • cites [13] Barton W, 2018, Gut.

      Not checked in the free run.

    • cites [19] Clarke SF, 2014, Gut. source

      Not checked in the free run.

  • May combine two claims.

    Premisecitation

    In professional rugby players, distinct compositional and functional microbial characteristics are evident in the gut, including increased alpha diversity, enhanced microbial production of SCFAs, and greater metabolic capacity.

    “In professional rugby players, distinct compositional and functional microbial characteristics, including increased alpha diversity, enhanced microbial production of SCFAs, and greater metabolic capacity are evident in the gut [13, 19].”
    Quote in the paperNot a substantial claim0 of 2 sources checked
    • cites [13] Barton W, 2018, Gut.

      Not checked in the free run.

    • cites [19] Clarke SF, 2014, Gut. source

      Not checked in the free run.

  • May combine two claims.

    Premisecitation

    Increases in dietary protein can increase the amounts reaching the colon, where they are metabolized by colonic microbiota, leading to changes in microbiota populations and in microbial metabolites.

    “Increases in dietary protein can increase the amounts reaching the colon, where they are metabolized by colonic microbiota, leading to changes in microbiota populations and in microbial metabolites [178].”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [178] Ma N, 2017, Curr Protein Pept Sci

      Not checked in the free run.

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    The Bacteroides enterotype has been suggested to be most strongly correlated with frequent consumption of animal protein and saturated fat.

    “the Bacteroides enterotype has been suggested to most strongly be correlated with frequent consumption of animal protein and saturated fat.”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [172] Wu GD, 2011, Science. source

      Not checked in the free run.

  • May combine two claims.

    Premisecitation

    Microbiota diversity indices correlated positively with protein intake and serum creatine kinase, indicating that diet and exercise are both drivers of biodiversity in the gut.

    “Clarke et al. [19] reported microbiota diversity indices correlated positively with protein intake and serum creatine kinase indicating that diet and exercise are both drivers of biodiversity in the gut.”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [19] Clarke SF, 2014, Gut. source

      Not checked in the free run.

  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Premisecitation

    Whey protein has been associated with reductions in body weight and increased insulin sensitivity, and is frequently a major component of the athlete diet, particularly in strength and power sports.

    “whey protein has been associated with reductions in body weight and increased insulin sensitivity in the past, and is frequently a major component of the athlete diet, particularly in strength and power sports [186, 187].”
    Quote in the paperNot a substantial claim0 of 2 sources checked
    • cites [186] Belobrajdic DP, 2004, J Nutr source

      Not checked in the free run.

    • cites [187] Tipton KD, 2004, J Sports Sci source

      Not checked in the free run.

  • May combine two claims.

    Premisecitation

    High levels of BCAAs (leucine, isoleucine, and valine) can attenuate exercise-induced muscle fatigue and promote muscle-protein synthesis.

    “High levels of BCAAs (leucine, isoleucine, and valine) can attenuate exercise-induced muscle fatigue and promote muscle-protein synthesis [192].”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [192] Negro M, 2008, J Sports Med Phys Fitness

      Not checked in the free run.

  • May combine two claims.

    Premisecitation

    Long-term diets are linked to certain compositional clusters in the gut microbiota: protein and animal fat are associated with Bacteroides enrichment, and simple carbohydrates with Prevotella enrichment.

    “Long-term diets have been linked to certain compositional clusters in the gut microbiota: protein and animal fat are associated with Bacteroides enrichment and simple carbohydrates with Prevotella enrichment [172].”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [172] Wu GD, 2011, Science. source

      Not checked in the free run.

  • May combine two claims.

    Interpretationreasoning

    High-protein diets may negatively impact gut microbiota diversity for athletes in endurance sports who consume lower amounts of energy, carbohydrates, and dietary fiber, while athletes in resistance sports following a high-protein, low-carbohydrate, high-fat diet show a decrease in SCFA-producing commensal bacteria.

    “It seems that high-protein diets may have a negative impact on gut microbiota diversity for athletes in endurance sports who consume lower amounts of energy, carbohydrates, and dietary fiber, while athletes in resistance sports that follow a high-protein, low-carbohydrate, and high-fat diet demonstrate a decrease in SCFA-producing commensal bacteria.”
    Quote in the paperSubstantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Interpretationcitation

    The difference between these two studies may be due to differences in analyses: Clarke et al. only assessed the V4 region, while the present study used the V3 and V4 region.

    “The difference between these two studies may also be due to differences in analyses, as Clarke et al. [19] only assessed the V4 region of the gene, while the present study used the V3 and V4 region (see Table 4).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [19] Clarke SF, 2014, Gut. source

      Not checked in the free run.

  • May combine two claims.

    Premisereasoning

    No changes in compositional microbiota diversity were detected after the ten-week protein supplementation intervention, in contrast to Clarke et al., which may relate to the low percentage of protein intake.

    “In contrast to Clarke et al. [19], no changes in compositional microbiota diversity were detected after the ten-week intervention, which may relate to the low percentage of protein intake.”
    Quote in the paperSubstantial claim0 of 2 sources checked
    • cites [19] Clarke SF, 2014, Gut. source

      Not checked in the free run.

    • cites [196] Moreno-Perez D, 2018, Double-Blind Pilot Study Nutrients

      Not checked in the free run.

  • May combine two claims.

    Interpretationreasoning

    Because BCAAs are not produced by the human body and must come from the diet, having a gut microbial community containing Prevotella spp. that can synthesize BCAAs or influence other microbes to produce them would be highly beneficial to athletes requiring rapid recovery from intense exercise.

    “Since BCAAs are not produced by the human body and need to come from the diet, having a gut microbial community that contains Prevotella spp. to either synthesize BCAAs or alternatively influence other microbes to produce these amino acids would be highly beneficial to athletes who require a rapid recovery from intense exercise.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Premisecitation

    The athletes in Clarke et al. met all recommended dietary intake requirements, while the athletes in Jang et al. had insufficient carbohydrate and dietary fiber intake compared to standard macronutrient distribution ranges.

    “the study by Clarke and colleagues [19] met all of the recommended dietary intake requirements, while the athletes in the investigation by Jang et al. [11] had insufficient carbohydrate and dietary fiber intake (compared to standard macronutrient distribution ranges).”
    Quote in the paperSubstantial claim0 of 2 sources checked
    • cites [19] Clarke SF, 2014, Gut. source

      Not checked in the free run.

    • cites [11] Jang LG, 2019, J Int Soc Sports Nutr source

      Not checked in the free run.

  • May combine two claims.

    Premisecitation

    A ketogenic diet alters gut microbiota composition, leading to an increase in Akkermansia abundance.

    “a ketogenic diet alters gut microbiota composition leading to an increase in Akkermansia abundance.”
    Quote in the paperNot a substantial claim0 of 2 sources checked
    • cites [66] Olson CA, 2018, Cell. source

      Not checked in the free run.

    • cites [202] Gentile CL, 2015, Nutr J source

      Not checked in the free run.

  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Premisecitation

    These recommendations aim to support rapid gastric emptying, water and nutrient absorption, and adequate perfusion of the splanchnic vasculature.

    “These recommendations aim to support rapid gastric emptying, water and nutrient absorption and adequate perfusion of the splanchnic vasculature [221].”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [221] Jeukendrup AE, 2017, Sports Med source

      Not checked in the free run.

  • May combine two claims.

    Premisecitation

    Akkermansia fed to mice has a positive impact on reducing seizures, providing a potential mechanism for the neuroprotective effects of a ketogenic diet.

    “Akkermansia fed to mice has a positive impact on reducing seizures, providing a potential mechanism for the observed neuroprotective effects of a ketogenic diet [66, 202].”
    Quote in the paperNot a substantial claim0 of 2 sources checked
    • cites [66] Olson CA, 2018, Cell. source

      Not checked in the free run.

    • cites [202] Gentile CL, 2015, Nutr J source

      Not checked in the free run.

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    Nutritional strategies (i.e., avoiding fat and fiber) have been recommended to reduce the risk of GI distress before and during training and competition.

    “Nutritional strategies (i.e., avoiding fat and fiber) have been recommended to reduce the risk of GI distress before and during training and competition [220].”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [220] Thomas DT, 2016, Med Sci Sports Exerc source

      Not checked in the free run.

  • May combine two claims.

    Premisecitation

    Humans have much fewer enzymes to break down carbohydrates than bacteria, and what can be digested by these enzymes is absorbed in the small intestine.

    “In comparison to bacteria, humans have much fewer enzymes to break down carbohydrates [203] and what can be digested by these enzymes is absorbed in the small intestine.”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [203] Martens EC, 2016, Nature. source

      Not checked in the free run.

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    Prevotella has been noted to be associated with several disease states.

    “Prevotella has been noted to be associated with several disease states.”
    Quote in the paperNot a substantial claim0 of 5 sources checked
    • cites [214] Liu Y, 2016, Clin Gastroenterol Hepatol source

      Not checked in the free run.

    • cites [215] Moreno-Indias I, 2016, Am J Transl Res

      Not checked in the free run.

    • cites [216] Michail S, 2015, FEMS Microbiol Ecol source

      Not checked in the free run.

    • cites [217] Li J, 2017, Microbiome. source

      Not checked in the free run.

    • cites [218] Chen W, 2012, PLoS One

      Not checked in the free run.

  • May combine two claims.

    Premisecitation

    The change in beta diversity was mirrored in the combined exercise and protein supplementation group, suggesting a robust positive effect of whey protein on the taxonomic richness of the gut virome.

    “this change was mirrored in the combined exercise and protein supplementation group, suggesting a robust positive effect of whey protein on the taxonomic richness of the gut virome.”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [199] Cronin O, Barton W, Skuse P, Penney NC, Garcia-Perez I, Murphy EF, et al. A Prospective Metagenomic and Metabolomic Analysis of the Impact of Exercise and/or Whey Protein Supplementation on the Gut Microbiome of Sedentary Adults. mSystems. 2018;3(3) https://doi.org/10.1128/mSystems.00044-18. source

      Not checked in the free run.

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    Enterotype assignment to the Prevotella group has been suggested to be associated with high-fiber diets.

    “enterotype assignment to the Prevotella group has been suggested to be associated with high-fiber diets.”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [172] Wu GD, 2011, Science. source

      Not checked in the free run.

  • May combine two claims.

    Premisecitation

    Dietary fiber passes undigested from the small intestine into the colonic environment, and the gut microbiota relies on these fibers for energy, targeting them for disassembly with a combined toolkit of thousands of enzymes.

    “Dietary fiber passes undigested from the small intestine into the colonic environment [171] and the gut microbiota relies on these fibers for energy, which they target for disassembly with a combined ‘toolkit’ of thousands of enzymes [204].”
    Quote in the paperNot a substantial claim0 of 2 sources checked
    • cites [171] Sheflin AM, 2017, Gut Microbes source

      Not checked in the free run.

    • cites [204] El Kaoutari A, 2013, Nat Rev Microbiol source

      Not checked in the free run.

  • May combine two claims.

    Interpretationcitation

    Adding fiber, including resistant starch, to high-protein diets may help reduce potential negative effects of high protein consumption and may increase fat oxidation.

    “adding fiber, including resistant starch, to high protein diets may help reduce potential negative effects of high protein consumption [222] and may increase fat oxidation [202], further illustrating the importance of consuming adequate dietary fiber for gut and overall health.”
    Quote in the paperNot a substantial claim0 of 2 sources checked
    • cites [222] Toden S, 2006, Cancer Biol Ther source

      Not checked in the free run.

    • cites [202] Gentile CL, 2015, Nutr J source

      Not checked in the free run.

  • Probably not a substantial claim: may not pass S3 (load-bearing), S4 (based).

    Premisenone given

    Previous microbiome studies have repeatedly identified significant correlations of both diet and geographic location to abundances of Prevotella or Bacteroides.

    “Previous microbiome studies have repeatedly identified significant correlations of both diet and geographic location to abundances of Prevotella or Bacteroides.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Premisecitation

    Increased intake of dietary fiber does not have an overall Bifidobacterium-increasing effect, but specific dietary fibers selectively increase Bifidobacteria abundance.

    “Increased intake of dietary fiber does not have an overall Bifidobacterium increasing effect, however, specific dietary fibers have been shown to selectively increase Bifidobacteria abundance [205].”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [205] Simpson HL, 2015, Aliment Pharmacol Ther source

      Not checked in the free run.

  • May combine two claims.

    Premisecitation

    Prevotella has been shown to be higher in patients with depression, insulin resistance, non-alcoholic fatty liver disease, hypertension, and colon cancer.

    “Prevotella has been shown to be higher in patients with depression [214], insulin resistance [215], non-alcoholic fatty liver disease [216, 217], hypertension [217], and colon cancer [218].”
    Quote in the paperNot a substantial claim0 of 4 sources checked
    • cites [214] Liu Y, 2016, Clin Gastroenterol Hepatol source

      Not checked in the free run.

    • cites [215] Moreno-Indias I, 2016, Am J Transl Res

      Not checked in the free run.

    • cites [216] Michail S, 2015, FEMS Microbiol Ecol source

      Not checked in the free run.

    • cites [217] Li J, 2017, Microbiome. source

      Not checked in the free run.

  • Probably not a substantial claim: may not pass S3 (load-bearing), S4 (based).

    Interpretationreasoning

    The seemingly opposing effects of high-protein diets imply that protein-diet interactions are modulated by factors such as host body composition and exercise intensity.

    “These seemingly opposing effects of high-protein diets imply that protein-diet interactions are modulated by factors such as host body composition and exercise intensity.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Interpretationreasoning

    The types and amounts of fats consumed are likely important for the overall effects on the gut microbiota.

    “The types and amounts of fats consumed in each of these studies are also likely important for the overall effects on the gut microbiota.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Premisecitation

    In a 2-week diet swap study, changes in abundances of Bacteroides or Prevotella genera were not observed, but high-fiber, low-fat diets enriched bacterial genes for butyrate production and decreased genes for secondary bile acid synthesis.

    “While changes in abundances of Bacteroides or Prevotella genera were not observed in either group, the high-fiber, low-fat diets enriched bacterial genes for butyrate production and decreased genes for secondary bile acid synthesis, emphasizing the importance of identifying functional rather than compositional shifts.”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [207] O'Keefe SJ, 2015, Nat Commun source

      Not checked in the free run.

  • Probably not a substantial claim: may not pass S3 (load-bearing), S4 (based).

    Premisenone given

    Proteins from vegetable origin have a marked effect on gut microbiota.

    “Proteins from vegetable origin have a marked effect on gut microbiota but currently require investigation in athletes.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Interpretationreasoning

    Compared to sedentary controls, athletes have improved overall health, unless over-trained or in RED-S.

    “and improved overall health (unless over-trained or in RED-S).”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Premisecitation

    In rodents, lard feeding increased Bacteroides and showed signs of metabolic dysfunction.

    “In a rodent study, animals fed lard showed increases in Bacteroides and displayed signs of metabolic dysfunction.”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [229] Caesar R, 2015, Cell Metab source

      Not checked in the free run.

  • Probably not a substantial claim: may not pass S3 (load-bearing), S4 (based).

    Premisenone given

    Marked changes in microbiota composition are evident within 24 h of a dietary change.

    “Diet is an established modulator of gut microbiota composition and activity, with marked changes in microbiota composition evident within 24 h of a dietary change.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S4 (based).

    Premisenone given

    Diet is an established modulator of gut microbiota composition and activity.

    “Diet is an established modulator of gut microbiota composition and activity, with marked changes in microbiota composition evident within 24 h of a dietary change.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing), S4 (based).

    Premisenone given

    Higher intake of carbohydrate and dietary fiber in athletes appear to be associated with increased abundance of Prevotella.

    “Higher intake of carbohydrate and dietary fiber in athletes appear to be associated with increased abundance of Prevotella.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    Faecalibacterium produces a suite of metabolites and peptides with anti-inflammatory effects.

    “Faecalibacterium is widely recognized for its production of a suite of metabolites and peptides with anti-inflammatory effects [231].”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [231] Sokol H, 2008, Proc Natl Acad Sci U S A source

      Not checked in the free run.

  • Probably not a substantial claim: may not pass S4 (based).

    Interpretationnone given

    Individuals' microbiotas appear to be driven by their primary dietary patterns.

    “While individuals’ microbiotas appear to be driven by their primary dietary patterns”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Premisecitation

    In rodents, fish oil feeding increased lactic acid bacteria and protected from metabolic dysfunction.

    “In contrast, animals fed fish oil showed increased levels of lactic acid bacteria and were protected from metabolic dysfunction [229].”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [229] Caesar R, 2015, Cell Metab source

      Not checked in the free run.

  • Probably not a substantial claim: may not pass S3 (load-bearing), S4 (based).

    Premisenone given

    Increased intake of dietary fiber is associated with microbial richness and/or diversity.

    “Increased intake of dietary fiber is associated with microbial richness and/or diversity.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing), S4 (based).

    Premisenone given

    Protein intake appears to be a strong modulator of microbiota diversity.

    “Protein intake appears to be a strong modulator of microbiota diversity, with protein supplementation, such as whey, showing potential benefits that need further study in humans.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    SCFAs are linked to numerous metabolic benefits and a lean phenotype.

    “in support of purported links between SCFAs and numerous metabolic benefits and a lean phenotype [61–63].”
    Quote in the paperNot a substantial claim0 of 3 sources checked
    • cites [61] Hamer HM, 2009, Clin Nutr source

      Not checked in the free run.

    • cites [62] Koh A, 2016, Cell. source

      Not checked in the free run.

    • cites [63] Ridaura VK, 2013, Science. source

      Not checked in the free run.

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    Faecalibacterium spp. has been linked to a host of metabolic products with anti-inflammatory effects.

    “has been linked to a host of metabolic products with anti-inflammatory effects [231].”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [231] Sokol H, 2008, Proc Natl Acad Sci U S A source

      Not checked in the free run.

183 of 183

  • The paper relies on this without support.

    High-level athletes possess remarkable physiological and metabolic adaptations compared to sedentary individuals.

    “High-level athletes possess remarkable physiological and metabolic adaptations (including muscular strength/power, aerobic capacity, energy expenditure, and heat production) and provide unique insight in gut microbiome research.”

  • The paper relies on this without support.

    Many gut microbiota studies may be underpowered and may not control for important confounding variables such as diet, gender, ethnicity, GI problems, and antibiotics.

    “Furthermore, many gut microbiota studies may be underpowered, and scientists may not be controlling for important confounding variables such as diet, gender, ethnicity, GI problems, antibiotics, etc.”

  • The paper relies on this without support.

    The role of exercise and associated factors and stressors on the gut microbiota has been less well described.

    “The role that exercise plays, in particular the associated factors and stressors, such as sport/exercise-specific diet [11], environment [12], and their interactions, on the gut microbiota have been less well described.”

  • The paper relies on this without support.

    Athletes exemplify exercise, dietary, and athletic factors on a generally consistent and long-term basis.

    “Athletes, although diverse as a population given the wide variety of different types of exercise/fitness/athletic training, competition, dietary practices and attributes, exemplify these factors on a generally consistent and long-term basis.”

  • The paper relies on this without support.

    Findings from animal models (mice, piglets) can be extrapolated to humans, including athletes.

    “These preclinical models indicate a causal, microbiota-dependent relationship between nutrition and growth promotion which may have implications for younger athletes.”

  • The paper relies on this without support.

    The gut microbiota composition measured in feces reflects the gut microbiota throughout the GI tract.

    “feces is the only sample material used in the analyses of the gut microbiota from the studies included in this review.”

  • The paper relies on this without support.

    Dietary protein effects on gut microbiota observed in non-athletes apply to athletes.

    “It seems that high-protein diets may have a negative impact on gut microbiota diversity for athletes in endurance sports who consume lower amounts of energy, carbohydrates, and dietary fiber, while athletes in resistance sports that follow a high-protein, low-carbohydrate, and high-fat diet demonstrate a decrease in SCFA-producing commensal bacteria.”

  • The paper relies on this without support.

    The studies reviewed are sufficiently comparable to draw general conclusions about diet and gut microbiota.

    “The variation in microbial analysis across different studies can make comparing/contrasting study findings difficult.”

  • The paper relies on this without support.

    LPS can be incorporated into lipid micelles formed during fat digestion.

    “LPS can be incorporated into lipid micelles formed during fat digestion”

  • The paper relies on this without support.

    Certain gut microbes may be important in regulating the incorporation of LPS into lipid micelles.

    “and certain gut microbes may be important in regulating this process.”
10 of 10

Claims other papers make about this one

Each is checked against this paper’s own text: does it say what the citing paper says it does?

Self-check

Percentages, sums and reported differences re-computed from the paper’s own numbers.

Each contradiction between two passages listed here was confirmed by an independent check.

  • Whey-protein group's gut virome beta diversity both decreases and increases

    Major

    Table 2 reports decreased gut virome beta diversity in participants consuming protein, but the text reports a significant increase in the whey-protein-only group.

  • Half-marathon study is attributed to the wrong reference

    Minor

    The cited reference [20] lists Zhou and colleagues' study of bacterial communities in human habitats, not the Zhao half-marathon study described in the text.

  • Post-surgery microbiota claim cites a pain-management study

    Minor

    The text cites [162] for a reported reduction in Firmicutes after bariatric surgery, but reference [162] is listed as a study of postoperative pain management in nursing.

3 of 3

Cites

Flagged first, then by citations

2 of the 247 references couldn’t be matched to a known paper.

Research works printed but not linked: 23

  1. Dudek-Wicher RK, 2018, Prz Gastroenterol, 13, 85
  2. Bermon S, 2015, Exerc Immunol Rev, 21, 70
  3. Barton W, 2018, Gut., 67, 625
  4. O'Sullivan A, 2015, Nutr Metab Insights, 8, 1
  5. Ishiguro E, 2018, Gut microbiota: interactive effects of nutrition and health: Elsevier
  6. Rodriguez JM, 2015, Microb Ecol Health Dis, 26, 26050
  7. Barb JJ, 2016, PLoS One, 11
  8. Liu Z, 2008, Nucleic Acids Res, 36
  9. Khan MJ, 2016, J Obes, 2016, 7353642
  10. Evans CC, 2014, PLoS One, 9
  11. Larsen N, 2010, PLoS One, 5
  12. Queipo-Ortuno MI, 2013, PLoS One, 8
  13. Clavel T, 2014, The prokaryotes
  14. Taniguchi H, 2018, Phys Rep, 6
  15. Gisolfi CV, 2000, News Physiol Sci, 15, 114
  16. Abbas A, 2014, J Gastroenterol Hepatol Res, 3, 1103
  17. Feldman M, 1982, J Appl Physiol Respir Environ Exerc Physiol, 53, 851
  18. Brock-Utne JG, 1988, S Afr Med J, 73, 533
  19. Ma N, 2017, Curr Protein Pept Sci, 18, 795
  20. Negro M, 2008, J Sports Med Phys Fitness, 48, 347
  21. Moreno-Perez D, 2018, Double-Blind Pilot Study Nutrients, 10, 337
  22. Moreno-Indias I, 2016, Am J Transl Res, 8, 5672
  23. Chen W, 2012, PLoS One, 7

Cited by

Sorted by citations

Related

Authors
Mohr, A. E., Jäger, R., Carpenter, K. C., Kerksick, C. M., Purpura, M., Townsend, J. R., West, N. P., Black, K., Gleeson, M., Pyne, D. B., Wells, S. D., Arent, S. M., Kreider, R. B., Campbell, B. I., Bannock, L., Scheiman, J., Wissent, C. J., Pane, M., Kalman, D. S., Pugh, J. N., Ortega-Santos, C. P., ter Haar, J. A., Arciero, P. J., & Antonio, J.
Affiliations
  • Arizona State University (US)
  • Increnovo LLC (United States) (US)
  • Lindenwood University (US)
  • Lipscomb University (US)
  • Griffith University (AU)
  • Loughborough University (GB)
  • University of Canberra (AU)
  • University of South Carolina (US)
  • Texas A&M University (US)
  • University of South Florida (US)
  • Nutrasource (CA)
  • Liverpool John Moores University (GB)
  • College of Health SolutionsArizona State University Phoenix AZ USA
  • International Probiotic Association Los Angeles CA USA
  • Skidmore College (US)
  • Exercise and Sport ScienceNova Southeastern University Davie FL USA
Corresponding author
Mohr, Alex E.
ORCID
Venue
Journal of the International Society of Sports Nutrition
Publisher
Informa UK Limited
Published
2020-01-03
Volume
17
Issue
1
Pages
24-24
ISSN
1550-2783 (ISSN-L)
DOI
10.1186/s12970-020-00353-w
PMC
PMC7218537
OpenAlex
W3025067031
Semantic Scholar
d5aebbded1fca1f19634f1e5eb972c85483bb76b
Cited by
378
References
247
Citations by year
2026: 55 · 2025: 60 · 2024: 73 · 2023: 62 · 2022: 77 · 2021: 43 · 2020: 7
FWCI
4.95
Type
journal article
Language
en
Open access
Licence
Locations
  • Journal of the International Society of Sports Nutrition (publishedVersion, cc-by)
  • PubMed Central (publishedVersion, cc-by)
  • PubMed (publishedVersion)
  • Liverpool John Moores University (acceptedVersion)
  • Griffith Research Online (submittedVersion, cc-by)
  • Rutgers University Community Repository (Rutgers University) (submittedVersion)
  • Scholar Commons (University of South Carolina) (submittedVersion, cc-by)
  • DOAJ (DOAJ: Directory of Open Access Journals) (submittedVersion, cc-by-sa)
  • Figshare (submittedVersion, cc-by)
Topics
  • Life Sciences › Biochemistry, Genetics and Molecular Biology › Molecular Biology › Gut microbiota and health
  • Life Sciences › Agricultural and Biological Sciences › Food Science › Probiotics and Fermented Foods
  • Health Sciences › Medicine › Gastroenterology › Gastrointestinal motility and disorders
Keywords
gut microbiota, athletes, physical activity, athletic performance, microbial diversity, mucosal immunity, gastrointestinal barrier function, energy metabolism, microbial metabolites, elite athletes
MeSH terms
Gastrointestinal Microbiome, Diet, Humans, Exercise, Athletic Performance, Sports Nutritional Physiological Phenomena

About these checks

Registry, retraction, Cites and statistics results are computed, not judged, with one exception: a printed reference that no index lists is read once by a model before it counts as a citation error. Claims are extracted by a model and kept only when their quote appears verbatim in the text; each cited source is then checked, with a model’s help, for whether it says what the claim relies on. Those verdicts can be wrong — read the claim’s quote and the cited source before relying on one.

Claims read by deepseek-v4.1-flash under definition version 3 (extract-v3) on 2026-10-08.

Classified by jev-1.13-20260917 (gold-guideline-v0.2) on 2026-10-08.

Statistics and arithmetic are recomputed, not judged.

Confidence bands are shown only for fields calibrated on our annotated test set. None is calibrated yet, so no band is shown.

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