Exercise, Nutrition and Gut Microbiota: Possible Links and Consequences

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Costa et al. Int J Sports Exerc Med 2017, 3:069
Volume 3 | Issue 4
DOI: 10.23937/2469-5718/1510069
International Journal of
Sports and Exercise Medicine
Citaon: Costa AV, Leite G, Resende A, Blachier F, AH Lancha Jr (2017) Exercise, Nutrion and Gut
Microbiota: Possible Links and Consequences. Int J Sports Exerc Med 3:069. doi.org/10.23937/2469-
5718/1510069
Received: July 13, 2016; Accepted: August 21, 2017; Published: August 24, 2017
Copyright: © 2017 Costa AV, et al. This is an open-access arcle distributed under the terms of the
Creave Commons Aribuon License, which permits unrestricted use, distribuon, and reproducon
in any medium, provided the original author and source are credited.
• Page 1 of 8 •
Open Access
ISSN: 2469-5718
Costa et al. Int J Sports Exerc Med 2017, 3:069
Exercise, Nutrion and Gut Microbiota: Possible Links and Con-
sequences
AV Costa1, G Leite1, A Resende1, F Blachier2* and AH Lancha Jr1*
1School of Physical Educaon and Sport, University of São Paulo, Brazil
2UMR PNCA, Agro Paris Tech, INRA, University Paris-Saclay, Paris, France
*Corresponding authors: AH Lancha Jr, School of Physical Educaon and Sport, University of São Paulo, Brazil, Tel:
+33144088676, E-mail: lanchajr@usp.br;
F Blachier, UMR PNCA, Agro Paris Tech, INRA, University Paris-Saclay, Paris, France, Tel: +33144088675, Fax: +33144081858,
E-mail: francois.blachier@agroparistech.fr
Abstract
Gut microbiota plays an important role in the modulation
of physiological processes associated with the digestion
of nutrients, immune system and control of energy homeo-
stasis. Changes in gut microbiota composition have been
associated notably with obesity, diabetes, and inammatory
diseases. Diet is one of the major factors capable of modu-
lating the intestinal microbiota composition. In addition, the
literature has shown that exercise can affect the gut micro-
biota composition and modulate the balance between the
interaction of host and benecial microbiota. Physical exer-
cise improves the diversity and relative amounts of bacterial
species under different nutritional contexts. However, the
impact of exercise associated or not with dietary changes
on the gastrointestinal environment and consequences for
gut health remain poorly understood. Some proposals re-
garding the biological mechanisms possibly involved high-
light the short chain fatty acid production and alteration in
intestinal pH as main forms by which exercise may affect
gut microbiota composition. Thus, the aim of the present
review is to present an overview of the effects of physical
exercise associated with diet on the characteristics of the
intestinal microbiota.
Keywords
Exercise, Diet, Gut microbiota, Immune system, Short chain
fatty acid
commensal bacteria have been shown to be able to af-
fect gut metabolism and physiology by several mecha-
nisms, including the producon of various bacterial me-
tabolites from dietary and endogenous substrates [2].
While carbohydrate fermentaon is mainly considered
benecial for the host through the producon of Short-
Chain Fay Acids (SCFA) in the intesnal luminal con-
tent, protein fermentaon gives rise to a wide variety
of compounds, some of which could be detrimental for
gut health when present at excessive concentraon [3].
Some bacterial metabolites can be transferred through
the intesnal epithelium from the intesnal luminal con-
tent to the portal bloodstream reaching the liver, and
then, to the peripheral blood stream [4]. Some of these
metabolites have been shown to be acve on dierent
ssues, such as in the liver and adipose ssue, by inter-
fering with metabolism and physiology [5]. In addion,
high fat diet consumpon may be capable of promot-
ing gram-negave bacteria growth and favoring a local
inammaon, which would be harmful for gut health
[6]. There are several reports regarding the eects of
the diet but, recently, exercise was revealed as another
factor capable of inuencing the diversity, composion
and metabolic acvity of gut microbiota, as well as its
fermentaon capacity and diet SCFA producon [6,7].
The aim of the present review is to present an overview
of the eects of physical exercise associated with diet on
the characteriscs of the intesnal microbiota.
REVIEW ARTICLE
Introducon
Gut microbiota is now established as a key player
in various aspects of health and diseases [1]. Recently,

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Gut Microbiota Composion
The human gastrointesnal tract is colonized by ap-
proximately one trillion microorganisms known as gut
microbiota. This diversity represents a number much
larger than human cells [8,9]. Bacterial density varies
along the gastrointesnal tract due to the specic con-
dions of each poron, such as dierences in the gradi-
ent of pH, anmicrobial pepdes (including bile acids),
and in the amount of oxygen, which limits the growth of
some bacteria [10].
Human gut microbiota composion varies since the
birth up to two years of age, when the birth delivery
by vaginal or cesarean mode and early nutrion by
breaseeding or formula milk and the introducon of
new food modulate inially the microbial populaons,
quantavely and qualitavely, of the child toward
adulthood [11,12]. From there, several environmental
factors, mainly diet, exercise, aging, hygiene, medicine,
geographic area, pregnancy and the presence or not of
some disease will inuence the microbial composion
in a host-specic way [13,14]. In this complex commu-
nity of bacteria, two phyla appear to be the most pre-
dominant and common among individuals: Firmicutes
(60-80%) and Bacteriodetes (15-30%) [15]. The rst one
is the most abundant phylum covering, mainly, Clostrid-
ium, Ruminococcus, Lactobacillus and the butyrate-pro-
ducing bacteria, such as Eubacterium, Faecalibacterium
and Roseburia, which are known for their abundance in
healthy individuals. The Bacteroidetes phylum is com-
posed, primarily, by gram-negave bacteria, including
Bacteroides genus, which is recognized, mostly, for its
contribuon to the degradaon of complex glycans [16].
Furthermore, there are others phyla, which are part of
the gut microbiota, but in minor proporon, such as
Proteobacteria, Verrucomicrobia, Acnobacteria, Fuso-
bacteria and Cianobacteria [17].
The complexity between diet-related gut microbi-
ota and intesnal health
Diet inuences gut microbiota composion since it
provides senergy, nutrients and oligoelements/micro-
nutrients, which will be used by both the host and in-
tesnal bacteria. The gut microbiota produces several
vitamins and a range of enzymes, which will ferment
the nutrients that are not digested by human digesve
enzymes [18]. The most abundant SCFAs produced by
fermentaon of carbohydrates are acetate, propionate
and butyrate (which constute > 95% of the SCFA con-
tent). It has been shown that butyrate acts locally on
intesne by aecng metabolism and gene expression
in the colonic epithelium [19,20] while acetate and pro-
pionate reach systemic circulaon and are ulized by
other organs, such as adipose ssue and liver, and con-
tribute up to 10% of the energy required by the host
[21]. Moreover, as weak acids, they also help to main-
tain a slightly acidic pH in the proximal colon.
Nondigested proteins or pepdes might also be
substrates for microbial producon of SCFA [2]. How-
ever, microbial protein fermentaon by proteolyc
bacteria (for example some bacteria of Clostridium’s
group) yields a diverse range of metabolites, including
Branched-Chain Fay Acids (BCFA), lactate, and aromat-
ic components, and amines suldes, phenols and in-
doles [22]. Many of these protein fermentaon-derived
metabolites might have negave consequences on ep-
ithelial cell metabolism and barrier funcon, aecng
the host’s gut health [23]. Moreover, high protein diets
are usually accompanied by a reducon in carbohydrate
intake, which may not be benecial for host health [24].
Currently, lile is known about the eects of protein
supplementaon, associated (or not) with exercise.
Animal fat-rich diets quickly increase the abundance
of bacteria resistant to bile acids in humans, such as
Bacteroides and Bilophila, which can metabolize dier-
ent types of bile acids and promote the development
of inammatory bowel disease [25]. Furthermore, con-
sumpon of a high fat diet is capable of unbalancing the
proporons of Firmicutes/Bacteroidetes, raising Lipo-
polysaccharide (LPS) circulaon and the concentraon
of inammatory cytokines, favoring systemic inamma-
on [25,26].
The Eect of Physical Exercise on the Gut Mi-
crobiota
Studies in humans reporng the eects of physical
exercise on gut microbiota composion, diversity and
metabolic acvity are limited. Clarke, et al. [27] accom-
plished the sole study performed with healthy individu-
als. In this pioneering work, elite rugby players were re-
cruited, and, in agreement with several animal studies,
this study reported that athletes displayed an increase
of the gut microbiota richness and diversity (22 disnct
phyla), and also a decrease of systemic pro-inammato-
ry cytokines [27] (Table 1). The authors reported this bi-
ota prole in individuals with exercise training program
in athletes as compared to sedentary controls group.
However, the most relevant insight on the eect of
exercise on gut composion was provided by exper-
imental models. Matsumoto, et al. [28] were the rst
authors to demonstrate that chronic voluntary physical
exercise is able to change the composion of rat gut mi-
crobiota [28]. Some studies performed aerwards asso-
ciated physical exercise with some pathological states
or dietary intervenon (Table 1).
A study performed with polychlorinated biphenyls
(pollutant model) demonstrated that voluntary physical
exercise is able to cause changes in the biodiversity and
composion of microbiota in mice, and aenuated the
eects of the pollutant contaminaon of the microbiota
[29]. Furthermore, under dierent dietary condions,
voluntary exercise appears to reshape the gut microbi-
ota. Evans, et al. [25] proposed that physical exercise

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Table 1: Exercise and microbiota studies.
Reference Exercise
training
Subjects Groups Analyses of gut
microbiota
Results
Matsumoto, et
al. [28]
Voluntary
exercise; 5
weeks
Animals Exercised and
sedentary
group
PCR-TGGE and a
sequencing analysis
for bacterial DNA and
HPLC for organic
acids
Increase of n-butyrate
concentrations and butyrate-
producing bacteria in exercise
group.
Choi, et al. [29]Voluntary
exercise; 5
weeks
Animals Model of
Polychlorinated
Biphenyls
(PCB)
administration
in exercise
and sedentary
groups
PhyloChip Array Exercise attenuates the decrease
of the abundance of bacterial taxa
and the phylum Proteobacteria after
PCB-treatment in both groups.
Exercise was capable to attenuate
PCB-induced changes on gut
microbiota. Activity level was
positively correlated with a shift in
abundance of the microbiota.
Queipo-Ortuño,
et al. [30]
Voluntary
exercise; 6
days
Animals Model of caloric
restriction in
exercise and
sedentary
groups
V2-V3 regions 16S
rRNA, PCR-DGGE
and qPCR
Increase of the phylum
Proteobacteria, decrease of
phyla richness and of the genus
Bidobacteria was observed in
exercise plus CR group. Moreover,
this group showed increase in
Clostridium and Enterococcus
and decrease of B. coccoides-E.
rectal and Lactobacillus unlike the
changes in exercise group without
CR.
Evans, et al.
[25]
Voluntary
exercise; 12
weeks
Animals Model of LFD
and HFD in
exercise and
sedentary
groups
V4 region 16S rRNA,
TRFLP and qPCR
Exercise increased Bacteroidetes
and decreased Firmicutes in
both LFD and HFD groups and
displayed a trend toward to
increase Bacteroidetes/Firmicutes
ratio. Actinobacteria levels were
lower in LFD-e than LFD-s. Also,
exercise increased the content of
the families Lachnospiraceae and
Ruminococcaceae and decreased
Lactobacillaceae in both diets.
Kang, et al. [45]Controlled
exercise; 60
min/d; 5 d/
week;
16 weeks
Animals Model of ND
and HFD in
exercise and
sedentary
groups
V3-V5 regions 16S
rRNA, Illumina MiSeq
and qPCR
Exercise was capable to reduce
the levels of Streptococcus genus
in HFD group. Also, there was a
signicant increase in Firmicutes
and decrease in Bacteroidetes
phyla in HFD-e compared to HFD-s.
Petriz, et al.
[32]
Controlled
exercise; 30
min/d; 5 d/
week; 4 weeks
Animals Control,
hypertensive
and obese
groups
V5-V6 regions
16S rRNA, 454
GS FLX Titanium
sequencer platform
(pyrosequecing)
Exercise reduced Streptococcus
genus in control rats, increased of
Allobaculum genus and reduced
Aggregatibacter and Suturella in
hypertensive rats and increased
Lactobacillus levels in obese rats.
At post exercise, only obese rats
showed more abundance of some
bacteria species.
Lambert, et al.
[35]
Controlled
exercise; LIT;
5 d/week; 6
weeks
Animals Diabetic type
II and control
groups
qPCR Exercise increased the abundance of
Firmicutes species (Lactobacillus spp.
and Clostridium leptum cluster IV)
and reduced Bacteroides/Prevotella
spp. and Methanobrevibacter spp.
in both control and diabetic groups.
Bidobacterium spp. was greater
in exercised control but not diabetic
group.

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only in the group submied to exercise, as we observe
on Evans, et al. [25] research, hence supporng the hy-
pothesis that exercise causes changes in gut microbiota
independent of changes in diet [26].
Short term (6 days) voluntary exercise showed that
nutrional status and physical acvity alter gut micro-
biota diversity in dierent manners. When exercise is
combinated with food restricon protocol (restricng
access for 23 hours per day and conned to running
wheels except during a 60 min meal), a negave impact
on bacterial richness is reported with respect to the Lac-
tobacillus and Bidobacterium genera [30]. The caloric
restricon was also able to modify the phyla, even in
the presence of exercise [30] (Table 1). It seems that ex-
modies the bacterial balance in the gut, with alteraon
of the major phyla levels, and increase of the relave
proporon of butyrate-producing bacteria (Clostridia-
ceae, Lachnospiraceae and Ruminococcaceae). The au-
thors appoint that the exercise pracce would be able
to prevent the eects of a High Fat Diet (HFD) [25]. In
fact, Campbell, et al. [26] showed that exercise is able
to modify not only the specic populaons of commen-
sal bacteria in the gut, but also cause morphological
changes in gut microenvironment. In the Campbell et al.
study [26], the exercised group showed reduced intes-
nal inammaon due to a high-fat diet and morpho-
logical characteriscs similar to the control. Likewise, in
a previous study, Faecalibacterium prausnitzi and Lach-
nospiraceae group (a Clostridia-cluster) were detected
Liu, et al. [31]Voluntary
exercise; 11
weeks
Animals
(Ovariectomized
female rats)
Model of LCR
and HCR in
exercise and
sedentary
groups; all
groups with
HFD
V4 region 16S rRNA,
Illumina MiSeq
Exercise decreased the abundance
of Firmicutes in LCR and increased
in HCR group. Also, it was capable
to increase Proteobacteria and
Cyanobacteria phyla in LCR, but
decreased in HCR group. At family
level, exercise decreased the
abundance of Ruminococcaceae
and Lachnospiraceae in LCR,
but increased in HCR. Exercise
increased Clostridiaceae and,
mainly, Clostridium genus, in both
exercise groups.
Mika, et al. [34]Voluntary
exercise; 6
weeks
Animals Healthy
juveniles and
adults with
exercise and
sedentary
groups
V4 region 16S rRNA,
qPCR
The juvenile runners, although
less diverse and richness than
their adults counterparts, showed
more changes as an increase in
Bacteroidetes and a decrease in
Firmicutes and Proteobacteria
phyla, which remains over 25 days
even without exercise.
Campbell, et al.
[26]
Voluntary
exercise; 12
weeks
Animals Model of ND
and HFD in
exercise and
sedentary
groups
TRFLP and 454 GS
FLX 454 Genome
Sequencer platform
(pyrosequencing)
Allobaculum spp. and Clostridiales
were enriched within the exercise
group in ND. Faecalibacterium
prausnitzi was detected only in
exercise groups in both ND and
HFD and Lachnospiraceae was
not present in the HFD-e or HFD-s
groups.
Denou, et al.
[33]
Controlled
exercise; HIIT;
3 d/week; 6
weeks
Animals Model of ND
and obesity-
inducing HFD
in exercise
and sedentary
groups
V3 region 16S rRNA,
Illumina MiSeq and
qPCR
HIIT increased the overall
richness of the microbiota in the
colon of obese mice, mainly,
within Bacteroidetes phylum and
Bacteroidales order unlike to the gut
microbiota composition in HFD-s
group.
Clarke, et al.
[27]
No intervention Humans Athletes
(rugby players)
and healthy
untrained
controls
V4 region 16S
rRNA, 454 Genome
Sequencer
FLX platform
(pyrosequencing)
Athletes showed a higher
richness with less abundance of
Bacteroidetes phylum. The family
Akkermansiaceae and the genus
Akkermansia showed higher
levels in athletes when compared
to control group with high BMI
and lower levels of Bacteroides,
Lactobacillaceae and Lactobacillus
when compared to control group
with low BMI.
d: day; LIT: Low Intensity Training; HIIT: High Intensity Interval Training; LFD: Low Fat Diet; ND: Normal Diet; HFD: High Fat Diet;
LFD-e: Low Fat Diet plus exercise; LFD-s: Low Fat Diet within sedentary group; HFD-e: High Fat Diet plus exercise; HFD-s: High
Fat Diet within sedentary group; LCR: Low Capacity Running; HCR: High Capacity Running.

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more plasc and sensive to environmental changes
during early life. Then, exercise iniated during the ju-
venile period may show a more robust impact on the
gut microbiota than exercise iniated in adulthood [34].
In other words, the changes that occur in childhood may
last longer even with the absence of exercise than the
changes occurring later. The authors show that exer-
cise-induced alteraons in microbiota during early life
contribute to metabolic consequences such as increased
SCFA producon, increased energy expenditure and re-
duced fat accumulaon in the adipose ssue. Indeed,
increased Bacteroidetes phyla along with decreased Fir-
micutes phyla within the gut have been associated with
these metabolic consequences. The results obtained by
Denou, et al. [33] reinforce this proposion [33-35].
It is important to observe that only one study regard-
ing gut microbiota and exercise science was carried out
with athletes [27], a populaon in which the amount of
exercise training is very large and intense, and its out-
comes are dierent when compared with voluntary ex-
ercise performed in some animals’ protocols or short
session of moderate exercise performed by acve indi-
viduals, as shown in Table 1.
Possible Mechanisms Connecng Physical Ex-
ercise and Gut Microbiota
The eect of exercise on microbiota is sll largely un-
known. They are likely to be mediated, at least in part,
by altering parameters that inuence the intesnal mi-
croenvironment.
Short chain fat acids
Exercise may increase butyrate-producing bacteria
species [25,28]. Matsumoto, et al. [28] were the rst to
show that chronic voluntary physical exercise in animals
is able to change SCFA producon (n-butyrate) in the ce-
cum with modicaons in butyrate-producing bacteria
species. In addion, this study reported alteraon in the
cecal microbiota prole aer exercise. These authors
explain that part of the benecial eects of exercise re-
lated to microbiota and subsequent variaons in intes-
nal health may be related to changes in the SCFA prole,
especially for butyrate concentraons [28]. This shi in
butyrate bacteria producon in exercise group was also
shown by Evans, et al. [25].
The inuence of physical exercise on the composi-
on of the microbial environment has been linked to a
decreased pH in the gut from SCFA producon. Speci-
cally butyrate promotes cell dierenaon and cell cy-
cle arrest, inhibits the enzyme histone deacetylase, and
decreases the transformaon of primary to secondary
bile acids promong colonic acidicaon [36]. Changes
in intesnal luminal pH may modify the environment in
such way that it becomes more favorable for the prolif-
eraon of some bacterial species [37].
ercise cannot aenuate the eect of caloric restricon,
whereas it would be able to cause improvements on gut
microbiota composion even under high fat diets.
Voluntary exercise with dierent aerobic capacies,
intensity, volume and frequency may present dier-
ent outcomes. Evans, et al. [25] showed a signicant
increase in the abundance of Bacteroidetes, while the
evidence provided by Liu, et al. [31] showed a reduc-
on in the abundance of Firmicutes and Proteobacteria
phylum. Apart from both studies exposing the animals
to the same diet (HFD), these dierences observed be-
tween these two studies may originate from the dier-
ent experimental models used. Liu, et al. [31] study was
performed with ovariectomized female rats fed with
HFD, divided in High Capacity Running (HCR) and Low
Capacity Running (LCR), performed 11 weeks of volun-
tary exercise whereas Evans, et al. [25] performed 12
weeks voluntary exercise in male rats [25,31].
Petriz, et al. [32] proposed that training status and
intensity may be favorable to the proliferaon of spe-
cic families of bacteria [32]. The authors reported an
inverse correlaon between exercise and Clostridiace-
ae/Bacteroideae families and Ruminococus genera, and
a posive correlaon between Oscillospira in exercise
intensity. Aerobic training may be associated with a
favorable environment for Clostridiaceae, Bacteroide-
ae and Ruminococus, but an unfavorable environment
for Oscillospira due to acidicaon of the intesnal
environment. The proposion by Petriz, et al. [32] is in
agreement with modicaon of the gut environment
following high intensity or long period exercise. Exer-
cise should modify the environment in a favorable way
in terms of anaerobic bacteria populaon, or acidic en-
vironment since a decrease splanchnic blood ow and
oxygen supply occurs [32].
A recent study performed using High Intensity In-
terval Training (HIIT), demonstrated that HIIT exerts
opposed changes to the gut microbiota compared to
those imposed by obesity prole. Indeed, HIIT reduces
the predicted metabolic genec capacity of the fecal
microbiota, alters microbiota metabolic pathways, and
raises the possibility that this type of exercise training
may elicit some of its benecial eects on metabolism
through alteraons in the gut microbiome [33]. Howev-
er, this same study did not compare the dierent types
of exercise, such as connuous versus intermient, or
voluntary versus controlled exercise. These parameters
should be taken into consideraon in future invesga-
ons, since it remains unclear if the dierent types of
exercise can cause similar benecial eects regarding
gut microbiota, and intesnal health as suggested by
Liu, et al. and Petriz, et al. [31,32].
Related to the benecial impact of exercise on the
microbiota composion and diversity in the early life,
Mika, et al. [34] propose, “The sooner, the beer”. This
proposion is related with the fact that microbiota is

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stanal changes in the cecal microbiome composion
by smulang the growth of Firmicutes at the expense
of Bacteroidetes; and provoked outgrowth of several
bacteria in the Clostridia and Erysipelotrichi classes [44].
Anmicrobial acvity of the bile acids may elicit selec-
ve pressure on the bacterial communies in exercised
mice, leading to a shi of the gut microbiota composi-
on [11].
Conclusion and Perspecves
Exercise and diet are considered as possible factors
capable of modulang the intesnal balance between
the hosts by independent manners. Exercise has been
shown to improve the diversity of bacterial species and
richness under dierent nutrional strategies thus al-
lowing for instance to reduce the negave eects of
high fat diet. The modicaon in short chain fay acids
producon and alteraon in intesnal pH appear to be
the main forms by which exercise may aect gut micro-
biota composion.
It is important to note that, the studies performed up
to now, used solely the voluntary exercise as model. The
inuence of specic features related to exercise train-
ing, such as volume, intensity, types of exercise (aerobic
or anaerobic or combinaon) may impact gut microbio-
ta in dierent ways. Likewise, changes in the diet and/
or dierent pathological condions in the experimen-
tal design raise some dicules in evaluang only the
exercise eect on the gut microbiota composion and
metabolic acvity, as well as in comparing the results
Studies also have shown that butyrate may induce
mucin synthesis [38], and improve gut integrity by in-
creasing ght juncon assembly [34,39,40]. Mucins are
the protecve layer consisng of glycoproteins that help
forming the mucosal barrier lining of gastrointesnal
tract. This mucin layer has been recognized to play an
important role for the interacon with gut microbiota,
and may serve as a substrate for intesnal bacteria, as
Akkermansia muciniphila, and may alter the microbial
community composion [41].
Butyrate producon in the large intesne is associ-
ated with producon of Heat shock protein 70 (Hsp70).
Hsp70 maintains the funconal and structural proper-
es of intesnal epithelial cells in response to intense
exercise [42]. Since physical exercise and butyrate sm-
ulate epithelial cell Hsp70 producon, this may provide
structural and funconal stability to intesnal epithelial
cells undergoing unfavorable condions [25] ( Figure 1).
Bile acids
Physical acvity has been reported to increase excre-
on of primary bile acids in the gastrointesnal tract.
Since butyrate (that has been reported to be increased
by physical acvity) diminishes the conversion of bile ac-
ids into secondary bile acids, physical acvity may con-
sequently favor the rising of primary bile acids concen-
traons in the intesnal luminal content [23].
The primary bile acids have established an-micro-
bial acvity. In agreement with this hypothesis, Islam,
et al. [43] demonstrated that cholic acid induced sub-
Figure 1: Schematic view representing the possible ways by which physical exercise may impact the gut microbiota. This
includes Short-Chain Fatty Acid (SCFA) production by the microbiota, and bile acid production, as well as related alteration
of the luminal pH. Exercise may also impact gut transit time and intestinal immune response, which in turn may modify the
microbiota composition and metabolic activity.

ISSN: 2469-5718DOI: 10.23937/2469-5718/1510069
Costa et al. Int J Sports Exerc Med 2017, 3:069 • Page 7 of 8 •
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obtained in dierent studies and this may hinder our
understanding.
Further experiments, including molecular biology
studies, are obviously required in order to delineate the
precise mechanisms by which exercise impacts the in-
tesnal microbiota. Studies involving human volunteers
are also necessary to beer elucidate the exercise-mi-
crobiota relaonships and involved mechanisms.
This represents an important research area given the
evident impact of physical exercise on gut microbiota
composion and possible benet on gut health.
Acknowledgments
The authors thanks CAPES/PROEX that support this
publicaon.
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