Gut health and exercise performance training modulates gut healty profile and improves Endotoxemia. Regardless, these results show that the nutrient load is a key variable that can influence the gut community structure. Regularly exercising is one of the best things you can do for optimal health.

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The Science of Gut Health (\u0026 Why It Matters)

Gut health and exercise performance -

In particular there were lower levels of inflammatory markers known to bind to lipopolysaccharides — components found in the cell walls of gut bacteria. These are known to cause low-grade inflammation around the body, as well as playing a role in insulin resistance and the development of atherosclerosis, which in turn increases the risk of heart attacks and strokes.

Hannukainen and her colleagues say their work has also shown that exercise specifically reduced gut bacteria that have been associated with obesity. But it is still not clear exactly how exercise leads to changes in the community of microorganisms living in our guts, although there are several theories, says Woods.

Another potential mechanism, he explains, could be through exercise-induced alterations in the immune system, especially the gut immune system, as our gut microbes are in direct contact with the gut's immune cells. Exercising also causes changes in blood flow to the gut, which could affect the cells lining the gut wall and in turn lead to microbial changes.

Hormonal changes caused by exercise could also cause changes in gut bacteria. But none of these potential mechanisms "have been definitively tested", says Woods. Some elite athletes often suffer from exercise-induced stress due to the high-intensity training they do.

But the bacteria in our guts could help control the release of hormones triggered by exercise-related stress , while also potentially helping to release molecules that improve mood.

They can also help athletes with some of the gut problems they experience. Further research is however needed in this field. But there is still much more we can learn about how our physical activity affects the creatures living inside our guts, such as how different types of exercise and its duration might alter the microbial community.

It may also differ from individual to individual, based on their existing gut residents as well as BMI and other lifestyle factors, such as their diet, stress levels and sleep.

As scientists continue to tease out more of the secrets hidden within our gastrointestinal tracts, we may find new ways to improve our health through the bustling and diverse communities of organisms that call us their home.

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Science of Fitness Health. Share using Email. By Roberta Angheleanu 26th August The rich microbiota flourishing inside us may play a far greater role in the way exercise improves our health than previously thought. Athletes also tend to have increased gut microbial diversity compared to sedentary people.

Although there was no obvious difference in baseline microbial structures between responders and non-responders, Liu and colleagues were able to establish a model based on a machine-learning algorithm from baseline microbiome signatures which accurately predicted the exercise outcomes with respect to glycemic control and insulin sensitivity.

This raised the possibility of screening for individuals with high likelihood of exercise resistance using gut microbiota, so that personalized adjustments can be implemented in time to maximize the efficacy of exercise intervention.

To examine the potential causal relationship between the differentially shaped microbiotas, Liu et al. 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.

Together, the results from both the human and animal studies indicate that exercise may impose a differential impact on the composition and function of the gut microbiota across individuals. While future research is warranted, this study raised the possibility that the makeup of the gut microbiota may be a determiner for the efficacy of exercise i.

It may have been that exercise amplified subtle differences of the gut microbiota at baseline by remodeling the intestinal microenvironment such as inflammatory and oxidative status and local immunity critical for microbial growth and interaction, which ultimately lead to a divergent response of glycemic control to exercise intervention.

Finally, these findings further reinforce the notion that the functional capacity of gut microbiota, as assessed by metagenomics and metabolomics, can be significantly altered without major shifts in its community structure, and that changes in host phenotype may be more dependent on the metabolic capacity and metabolites of the microbiota, instead of the composition per se.

In the longest exercise intervention to date, Kern et al. Beta diversity changed in all exercise groups compared to control, with participants in the vigorous intensity group showing decreased heterogeneity.

In a study of acute exercise, both high intensity interval and moderate continuous training affected the gut microbiota in insulin resistant, sedentary individuals following a 2-week exercise intervention [ ].

This outcome has relevance to athletes as the increase in Bacteroidetes plays an essential role in the metabolic conversions of complex sugar polymers and degradation of proteins [ ]. There was also a decrease in Clostridium and Blautia genera.

Clostridium plays an important role in whole-body immune responses, while Blautia purportedly increases the release of proinflammatory cytokines [ ]. In addition, lower abundance of Blautia genus was associated with better whole-body insulin sensitivity.

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. Finally, in an observational study, Keohane et al. Alpha diversity increased throughout the ultra-endurance event and was evident as early as day 17 in the race.

This increase occurred independent of any change in cardiorespiratory fitness, with VO 2 max similar pre- and post-race. Variations in taxonomic composition included increased abundance of butyrate producing species and species associated with improved metabolic health and improved insulin sensitivity.

The functional potential of bacterial species involved in specific amino and fatty acid biosynthesis also increased. Specifically, the gene expression of functional metabolic pathways involved in L-isoleucine and L-lysine production increased, which play an important role in reducing muscular fatigue and damage during strenuous exercise [ ].

Microbial-derived lysine may also contribute to the body protein pool in humans [ ]. Changes in essential amino acid availability influence hematopoiesis, which in turn may increase oxygen carrying capacity and cardiorespiratory fitness [ ].

Many of the adaptations in microbial community structure and metaproteomics persisted at 3 months follow up. Overall, the mechanisms by which physical activity may promote a rich bacterial community and increased functional pathways have not been fully elucidated but likely involve a combination of intrinsic and extrinsic factors.

For example, physically active individuals are more likely to be exposed to their environmental biosphere e. Simultaneously, intrinsic adaptations to endurance training, such as decreased blood flow, tissue hypoxia, and increased transit and absorptive capacity can lead to changes in the GI tract [ , ].

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.

For instance, 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 [ , ].

Repeated bouts of aerobic exercise can increase GI transit time in healthy individuals and middle-aged patients with chronic constipation [ , , ]. However, at higher intensities e.

Aerobic exercise also increases fecal SCFA concentration which can decrease pH in the colonic lumen [ ]. Furthermore, metabolites that are a by-product of exercise and circulate throughout the body e. There is expected competition for nutrients and resources in every ecosystem, including the gut microbiota.

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. Anaerobic capacity and resistance exercise training may also influence community composition, though to date, no work has examined these parameters in relation to gut microbiota.

A single acute bout of prolonged excessive exercise can have a deleterious influence on intestinal function. Intense exercise redistributes blood from the splanchnic circulation to actively respiring tissues [ ].

Prolonged intestinal hypo-perfusion impairs mucosal homeostasis and causes enterocyte injury. Intestinal ischemia may result, particularly in the setting of dehydration, manifesting as abdominal cramps, diarrhea, or occasionally bloody diarrhea [ ].

This adverse effect is particularly the case in endurance sports [ ]. As a result, increased intestinal permeability ensues, thought to be driven by the phosphorylation of several tight junction proteins [ ]. These events render the gut mucosa susceptible to endotoxin translocation [ ]. 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 [ ].

Together these changes might help mitigate the effects of stress-induced intestinal barrier dysfunction. In humans, physical activity can improve gastrointestinal symptoms in subjects with irritable bowel syndrome [ ].

Collectively, these outcomes are evidence of a differential and dose-response effect of exercise on gut health, with the underlying mechanisms yet to be fully explored in healthy humans.

The current body of research supports the role of exercise as an important behavioral factor that can affect qualitative and quantitative changes in the gut microbial composition and function with benefits to the 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.

However, based on the current body of research, 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.

Indeed, exercise may be an important intervention to alter gut microbiota composition and restore gut symbiosis [ ]. Notably, certain taxa may be enriched in athletes such as the lean phenotype-associated A. muciniphila, and propionate producing Veillonella via metabolism of lactate.

In addition, higher diversity of microbiota composition was associated with lean phenotypes compared to that of obese individuals. It is likely that the diverse, metabolically favorable intestinal microbiota evident in the elite athlete is the cumulative manifestation of many years of high nutrient intake and high degrees of physical activity and training throughout youth, adolescence, and during adult participation in high-level sports [ ].

Future areas of gut microbiota research in relation to athletes and exercise is presented in Table 3. muciniphila and Veillonella. 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.

In researching the human gut microbiota, it is difficult to examine exercise and diet separately. This relationship is compounded by changes in dietary intakes often associated with physical activity e. Athletes often consume a diet that differs from the general population with implications on the composition of the gut microbiome.

This ability to rapidly change has implications in research design for the timing of measurements in exercise studies, as does dietary composition. Indeed, various food components, dietary patterns, and nutrients all have the potential to substantially alter the growth of different gut microbial populations.

Medication and diet are principal environmental factors that influence gut microbiota composition according to large-cohort studies [ , ]. The gut microbiota is an important factor that shapes both energy harvest and storage through metabolism of proteins and production of several metabolites including SCFAs, ammonia, sulfur-containing metabolites such as hydrogen sulfide and methanethiol, and neuroactive compounds such as tryptamine, serotonin, phenethylamine, tryptophan, and histamine [ , ].

Moreover, 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 [ ]. Animal studies have revealed communication between the gut microbiota and muscle, in which gut microbiota can affect muscle energy homeostasis by interfering with fat deposition, and lipid and glucose metabolism through various metabolites including SCFAs and secondary bile salts [ 17 ].

Broadly, 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 [ ].

During training and competition, fiber intake may be reduced to avoid potential GI issues including gas and distension [ ]. Here we describe the influence of total energy intake and the principal macronutrient classes protein, carbohydrate, and fat on the gut microbiota.

The GI tract represents the interface between ingested nutrients and the host where energy is effectively extracted. If not for the colonic microbiota, these nutrients would generally be eliminated via the stool without further absorption due to the limited digestive capability of the human large intestine [ ].

Therefore, 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 [ ]. In relation, the gut microbiota produces and releases an enormous array of compounds which may act upon host tissues modulating appetite, gut motility, energy uptake and storage, and energy expenditure [ , ].

Riedl et al. Clearly, the gut microbiota-host interaction can affect energy balance which has implications for weight gain or loss and body composition [ , ]. Strong evidence exists to support the role for the gut microbiota in energy balance by contributing to host digestive efficiency [ ].

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.

Gnotobiotic mice are inefficient at processing food, yet when colonized with conventional mouse gut biota they gain weight by increasing their energy stores [ ]. These results implicate the gut microbiota as an energy harvester, significantly affecting nutrient absorption by extracting energy from dietary substances.

Moreover, the high-energy diet increased circulating pro-inflammatory LPS. However, the impact of energy consumption on, and the ultimate extraction by, the gut microbiota is deeply intertwined with composition of the ingested diet. For example, obese mice fed a low saturated fat, high fruit and vegetable diet can take on microbiota characteristics of lean mice [ 63 ].

Moreover, mice consuming this diet regardless of lean or obese state gained less fat mass compared to lean and obese mice fed a high-saturated fat, low fruit and vegetable diet, typical of a Westernized diet.

In terms of human research there are few studies that have examined the effect of energy intake and energy expenditure on the gut microbiota.

The majority of this research has been conducted in relation to the study of obesity, weight loss, and malnourishment in children. 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 [ ].

Similar findings have been reported in relation to gene richness and altered metabolic pathways [ ]. However, the composition of the gut microbiota does appear to be sensitive to caloric balance as noted in subjects studied before, during, and after weight loss [ 38 ]. Furthermore, improved gene richness has been reported during weight-loss and weight-stabilization interventions in obese and overweight individuals [ ].

What remains unclear is the influence of energy stores obese or lean state versus the impact of energy intake positive or negative energy balance on ability to alter the gut microbiota.

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.

This finding suggests that the microbiota is responsive to energy balance degree of overfeeding as well as actual adiposity. Regardless, these results show that the nutrient load is a key variable that can influence the gut community structure. Moreover, in cyclists consuming high-energy, high-carbohydrate diets, abundances of health associated bacteria were high including Prevotella and Akkermansia and less characteristic of Western-associated microbiota [ 18 ].

However, it is difficult to remove physical activity influence from this, and gut microbiota research in athletes with high energy consumption requires further investigation. In contrast to high-energy intake and obesity, even less is known about the gut microbiota in undernutrition [ ].

Athletes can have a tremendous energy expenditure often requiring a corresponding increase in dietary intake to maintain energy balance. Occurring in both males and females, RED-S possesses a significant health risk.

To date, no study in athletes has addressed RED-S in relation to the gut microbiota. 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 [ ].

In humans, severe calorie restriction as a result of bariatric surgery offers an interesting research model to explore the effect on the gut microbiota [ ].

Changes such as reduced abundance of Firmicutes post-surgery have been reported [ ]. Although it is unclear if these modifications were caused by dietary change or weight loss.

While this ratio was negatively correlated with body weight, BMI, and body fat mass, the correlation was highly dependent on total calorie intake. Other alterations, such as the reduction of lactic acid forming bacteria, indicate a complex effect of severe calorie restriction.

Undernourished children have been observed to exhibit impaired gut microbiota development, with reduced relative abundance of several Bifidobacterium and Lactobacillus spp. as well as obligate anaerobic SCFA-producing taxa [ ]. This has led to the proposal that disrupted microbiota development impairs healthy bone and muscle growth during infancy [ ].

To explore the association between nutrition and the gut microbiota during infancy, Charbonneau et al. These animals were fed a representative Malawian diet with or without a bioactive substance in breast milk purified sialylated bovine milk oligosaccharides.

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.

These effects were also documented in gnotobiotic piglets using a similar design showing a greater ability to utilize nutrients from the diet [ ]. These preclinical models indicate a causal, microbiota-dependent relationship between nutrition and growth promotion which may have implications for younger athletes.

Various studies have explored the gut microbiota of anorexia nervosa patients with the majority of them being characterized by heterogeneity in the methodology and small sample sizes for review see: [ ]. 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 [ , , ].

Overall, energy balance is an overlooked factor in relation to the athletic gut microbiota. Not only is this relevant to improving performance, but also addressing the health status of those affected by RED-S.

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. Moreover, 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.

Despite the difficulties of studying macronutrient effects in isolation, there is evidence to support the assertion that dietary protein and fat consumption elicit both compositional and functional changes to the gut microbiota [ ]. David et al. 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 [ ]. Intervention studies have demonstrated that high-protein diets animal protein reduced fecal butyrate concentrations and butyrate-producing bacteria such as Bifidobacteria spp.

rectale [ , , ]. Fecal concentrations of potentially damaging N-nitroso compounds increase markedly in volunteers who consumed a high-protein, low-carbohydrate diet [ ]. Furthermore, a study of five male volunteers consuming high intakes of animal protein showed that fecal sulfide production is related to meat intake [ ]; notably, hydrogen sulfide is a compound associated with ulcerative colitis [ ].

Ma et al. This categorization has been criticized as an oversimplification, obscuring potentially important microbial variation, and may not be appropriate for the athletic population [ , ].

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

However, 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.

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 ].

In many athletic disciplines, as well as recreational exercise, protein supplementation e. The protein and microbiota diversity relationship is further supported by a positive correlation between blood urea levels a by-product of diets rich in protein and microbiota diversity [ 19 ].

In contrast, Jang et al. The inconsistency of these results compared to Clarke et al. In addition, 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.

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.

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 [ ]. Excessive fermentation of dietary protein in the GI tract is generally considered detrimental given the production of toxic by-products such as amines, phenols, indoles, thiols, and ammonia [ , ].

Further, 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 [ , ].

Estaki et al. A strong association was evident between protein intake and Bacteroides and, in particular, Ruminococcaceae and Lachnospiraceae , two of the most abundant families in human gut environments [ ], in explaining community diversity.

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 [ , ].

In comparing athletes to both high and low BMI non-athlete controls, Barton et al. Metabolites derived from dietary protein trimethylamine N-oxide, carnitines, trimethylamine, 3-Carboxymethylpropylfuranpropionic acid, and 3-hydroxy-isovaleric acid , muscle turnover creatine, 3-methylhistidine, and L-valine , vitamins and recovery supplements glutamine, lysine, 4-pyridoxic acid, and nicotinamide , as well as phenylacetylglutamine a microbial conversion product of phenylalanine were increased in athletes [ ].

Investigating the gut microbiota of cyclists, Petersen et al. High levels of BCAAs leucine, isoleucine, and valine can attenuate exercise-induced muscle fatigue and promote muscle-protein synthesis [ ].

While there is strong evidence showing that BCAAs do not enhance exercise performance [ , ], they may reduce central fatigue [ ] and attenuate muscle damage during prolonged 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. Specifically, protein supplementation increased the abundance of the Bacteroidetes phylum and decreased the presence of health-related taxa including Roseburia, Blautia , and B.

In contrast to Clarke et al. 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 [ ]. The difference between these two studies may also be due to differences in analyses, as Clarke et al.

Cronin et al. Individuals in the whey protein supplementation-only group experienced a significant increase in the beta diversity of the gut virome. Furthermore, 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.

Specifically, all bacteriophages bacteria-targeting viruses increased in the groups receiving whey protein were present in high relative abundance within the whey protein supplement. Therefore, it may be virus particles from whey protein transmit to the gut from consumption. The effect of the gut virome on the gut microbiota and host requires further investigation, particularly in relation to food and supplement consumption.

The source of protein, including its quality and digestibility, may influence the site of fermentation within the gut. Highly digestible proteins, such as whey, can be digested by host enzymes in the proximal intestine, reducing microbial fermentation. Similarly, plant-originated proteins are available for microbial fermentation in a more distal site given incomplete digestion by host enzymes, particularly at a higher protein level.

Evidence indicates proteins from vegetable origin have a more marked effect on microbial diversity than animal proteins [ ], however investigation in athletes is needed. By selecting dietary ingredients containing protein of rather high digestibility and quality, the amount of dietary protein reaching the large intestine may be diminished, thus limiting the quantity of residual protein available for protein fermenting bacteria.

As a consequence, the growth and activity of potential pathogens could be suppressed. 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.

The types and amounts of fats consumed in each of these studies are also likely important for the overall effects on the gut microbiota. For example, a ketogenic diet alters gut microbiota composition leading to an increase in Akkermansia abundance.

Moreover, 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 , ]. As a macronutrient class, carbohydrates including dietary fiber have a profound effect on the gut microbiota.

In comparison to bacteria, humans have much fewer enzymes to break down carbohydrates [ ] and what can be digested by these enzymes is absorbed in the small intestine. Therefore, carbohydrates in the form of dietary fiber represent enormous potential for modulation of gut microbiota based upon the chemistry and accessibility of specific dietary fibers to microbial groups.

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 [ ]. Long-term patterns of dietary fiber consumption can also shape the overall bacterial community type.

As previously discussed, enterotype assignment to the Prevotella group has been suggested to be associated with high-fiber diets. 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.

Endurance athletes are well known to follow diets that result in the consumption of high amounts of both simple and complex carbohydrates [ , ]. This dietary pattern, in combination with the substantial number of hours spent exercising on a weekly basis, led to the hypothesis that endurance athletes are likely to have increased abundance of the bacterial genus Prevotella [ ].

Prevotella is normally found in only a small percentage of healthy individuals in European and American cohorts [ 1 , 2 , 20 , ].

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

Prevotella is more often found in individuals from certain areas of Asia [ , ] and rural Africa [ ], and this enrichment for Prevotella is often reflective of diets high in complex carbohydrates including high dietary fiber from various sources including fruits and vegetables , egg food items, and high levels of vitamins and minerals [ , ].

However, Prevotella has been noted to be associated with several disease states. For instance, Prevotella has been shown to be higher in patients with depression [ ], insulin resistance [ ], non-alcoholic fatty liver disease [ , ], hypertension [ ], and colon cancer [ ].

One potential explanation for this phenomenon is that there are several strains within the Prevotella genus that exert pathogenic actions, which could help explain the bi-directional and almost opposing effects that Prevotella has shown to have in human health [ ].

For this, more in-depth metagenomic studies will be required to reveal the health- or disease-modulating properties of Prevotella , particularly at species and functional level [ ].

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

Many athletes may not be consuming enough fiber that feed commensal bacteria that produce beneficial byproducts for host metabolism and homeostasis [ 15 ]. Furthermore, adding fiber, including resistant starch, to high protein diets may help reduce potential negative effects of high protein consumption [ ] and may increase fat oxidation [ ], further illustrating the importance of consuming adequate dietary fiber for gut and overall health.

Petersen et al. smithii transcripts in professional cyclists using RNA sequencing. smithii increases the fermentation efficiency of many bacterial taxa in the gut, including those that ferment complex polysaccharides [ ]. This effect could benefit athletes because an increase in bacterial fermentation products such as SCFAs could be absorbed and utilized by the host.

Theoretically, this effect could enhance recovery from intense exercise and possibly race performance. SCFAs can improve skeletal muscle insulin sensitivity [ ], reduce inflammation [ ], and regulate satiety [ ], all of which may contribute to the improvements in body composition observed in this study.

Additionally, SCFAs are also energy substrates for numerous tissue types, including the colon [ ], adipose [ ] and muscle tissues [ ], indicating that SCFAs can contribute to enhanced energy harvest from the diet, ultimately providing support to healthy tissue growth and turnover.

Within the SCFAs, distinct clusters acetic acid, propionic acid, and butyric acid were observed by Barton et al. The same clusters were observed when positively correlating with individual taxa, in support of purported links between SCFAs and numerous metabolic benefits and a lean phenotype [ 61 , 62 , 63 ].

Like protein and carbohydrate, the specific effects of fat on the gut microbiota are difficult to isolate; however, the types of fats consumed appear to be important.

In a rodent study, animals fed lard showed increases in Bacteroides and displayed signs of metabolic dysfunction. In contrast, animals fed fish oil showed increased levels of lactic acid bacteria and were protected from metabolic dysfunction [ ].

Specific alterations included gut bacterial taxonomic shifts and transcriptional responses characteristic of carnivorous mammals, with higher concentrations of bile-tolerant bacteria presumably due to the extremely high-fat intake known to increase bile acid secretion [ ].

Diets high in fat could interact in various ways with the gut microbiota to facilitate the translocation of bacterial LPS generating chronic inflammation [ ]. LPS can be incorporated into lipid micelles formed during fat digestion, and certain gut microbes may be important in regulating this process.

In a short-term feeding study Wu et al. Although specific taxa changes varied between individuals, the high-fat diet slowed intestinal transit time by as much as 3 days. Metagenomic analysis indicated that functional shifts, including greater protein export and lipoic acid metabolism, were also associated with the high-fat diet.

Finally, the Bacteroides enterotype was most strongly correlated with reports of frequent consumption of animal protein and saturated fat. In comparison to high or periodized carbohydrate diet groups, the LCHF diet resulted in a more pronounced effect on the gut microbiota increasing the relative abundance of bacterial taxa with recognized capabilities for lipid metabolism.

The relative abundance of Bacteroides spp. was negatively correlated with fat oxidation and the relative abundance of Dorea was negatively correlated with an exercise economy test.

It appears that individual responsiveness to a high-fat diet may affect the amount of dietary fat that actually reaches the distal gut, where it could have associative effects on the gut microbiota. Furthermore, relative abundance of Faecalibacterium spp. was decreased in athletes after consumption of the LCHF diet.

Interestingly, Faecalibacterium spp. is one of the most abundant bacterial taxa present in the gut microbiota of healthy individuals and has been linked to a host of metabolic products with anti-inflammatory effects [ ]. Diets high in fat likely increase the pool of bile acids that elude epithelial absorption in the GI tract and interact with the gut microbiota [ ].

This interaction can impact the composition of the gut microbiota including reductions in the relative abundance of Faecalibacterium spp. Faecalibacterium is widely recognized for its production of a suite of metabolites and peptides with anti-inflammatory effects [ ].

Overall, there is a need for longer-term studies in different athletic cohorts examining the impact of diet on the structure and function of the gut microbiota. This approach is of particular importance as many athletes follow special dietary practices, such as during periods of intensified training prior to competition and offseason periods.

Research studies should investigate exercise-nutrient interactions that underpin adaptation and performance [ ]. Finally, further research is needed to determine the synthesis kinetics and clinical consequence of microbial by-products during increased nutritional status and metabolic demands during exercise.

Ultimately modulation of the microbiota and its fermentation capacity may be considered in dietary prescription for athletes.

This may include specific nutrient recommendations aimed at improving performance by enhancing certain metabolites during exercise and recovery, and limiting those that produce toxic metabolites that may made worsen the consequences of exercise stress [ 15 ]. This also includes the effects of high-protein and high-fiber intake.

Typical features include a higher abundance of health-promoting bacterial species, increased microbial diversity, functional pathways, and microbial-associated metabolites, stimulation of bacterial abundance that can modulate mucosal immunity, and improved barrier functions.

In comparison to sedentary controls, athletes have increased fecal metabolites and improved overall health unless over-trained or in RED-S. However, in sedentary individuals, exercise appears to positively modulate the composition and metabolic capacity of the human gut microbiota.

Given that athletes generally have a distinct diet, research on the gut microbiome in athletes must incorporate dietary and supplemental intake otherwise it might be a confounding factor in determining exercise-specific effects on the composition of the microbiome.

Investigators should examine how different types of sport, athlete, and physical training regimens influence the gut microbiota. The present review focuses on the discussion of the results from microbiota-related studies, however, a deep discussion of the methodological approaches of each manuscript was not possible due to the already extended content.

Future, more specific reviews in this research area should aim for discussing the results in the frame of their methodological approaches. Finally, much of the current research is cross-sectional and has relied on 16S rRNA sequencing. Therefore, future research should employ longitudinal designs as well as more advanced high-throughput sequencing and bioinformatic analyses to provide deeper understanding and functional causation of the gut microbial influence on athlete health and performance.

Ultimately this body of work will define how metabolic capabilities of gut microbiota are shaped by exercise and elucidate their functional roles influencing health and disease. Human Microbiome Project C.

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Sub Heading Can your gut health affect your physical performance? Main Image. Duration MAY 5, 3 MINUTE READ. Description Whether you're an amateur athlete or a weekend warrior, it's likely you put thought into your workout schedule.

How Do Gut Bacteria Affect Your Health? The trillions of bacteria in your digestive tract play an essential role in the healthy function of many bodily systems. Steve Hertzler, a nutrition scientist at Abbott. Does Exercise Affect the Gut? Can Gut Health Affect How You Exercise?

How Can You Support Your Gut Microbiota? If you want to increase the number and types of good bacteria in your gut to help improve health outcomes and support better physical endurance, consider these tips in addition to regular exercise: Aim for 25 to 35 grams of fiber per day.

Think beans, berries and whole grains. Consume a variety of colorful fruits and vegetables each day. Add fermented foods to your routine, such as kefir, kimchi and sauerkraut.

Consider a probiotic supplement. Consult your doctor for advice. RELATED ARTICLE. Heading 5 Smart Snacking Tips to Curb Hunger. Description Snacking is one of those habits that often gets a bad rap.

Heading 5 Snacks to Eat Before a Workout. Description Regularly exercising is one of the best things you can do for optimal health. Social Share. Enable Cookies. Learn more about cookies.

Exedcise gut Halth influences Protein intake for mood enhancement performance exervise resilience after performane exercise. Exercies, practicing moderate RMR and sleep on a regular basis results in a healthier edercise composition and, Gut health and exercise performance, better physical and mental health. The gut microbiota can be a great ally in exfrcise people get the maximum benefit from such Gut health and exercise performance in habit, says nutritionist and biologist Daniel Badiawho specializes in food and sport and is a professor at the Open University of Catalonia, Spain. According to the nutritionist, an unbalanced diet can cause intestinal discomfortsuch as abdominal distension, nutritional deficiencies, excessive fermentations, intestinal permeability and even a sense of increased fatigue after exercising. Following a healthy and balanced diet, meanwhile, promotes a healthy microbiota that could influence athletic performance. The key is the process of fermentation by bacteria of certain fiber-rich foods in the large intestine and the subsequent production of short-chain fatty acids SCFAs.