ArticleLiterature Review

Systematic review: Exercise-induced gastrointestinal syndrome-implications for health and intestinal disease

June 2017
Alimentary Pharmacology & Therapeutics 46(S2)

DOI:10.1111/apt.14157

Authors:

Ricardo J.S. Costa

Monash University (Australia)

Rhiannon Snipe

Deakin University

Cecilia M Kitic

The University of Queensland

Background “Exercise‐induced gastrointestinal syndrome” refers to disturbances of gastrointestinal integrity and function that are common features of strenuous exercise. Aim To systematically review the literature to establish the impact of acute exercise on markers of gastrointestinal integrity and function in healthy populations and those with chronic gastrointestinal conditions. Methods Search literature using five databases (PubMed, EBSCO , Web of Science, SPORTS discus, and Ovid Medline) to review publications that focused on the impact of acute exercise on markers of gastrointestinal injury, permeability, endotoxaemia, motility and malabsorption in healthy populations and populations with gastrointestinal diseases/disorders. Results As exercise intensity and duration increases, there is considerable evidence for increases in indices of intestinal injury, permeability and endotoxaemia, together with impairment of gastric emptying, slowing of small intestinal transit and malabsorption. The addition of heat stress and running mode appears to exacerbate these markers of gastrointestinal disturbance. Exercise stress of ≥2 hours at 60% VO 2max appears to be the threshold whereby significant gastrointestinal perturbations manifest, irrespective of fitness status. Gastrointestinal symptoms, referable to upper‐ and lower‐gastrointestinal tract, are common and a limiting factor in prolonged strenuous exercise. While there is evidence for health benefits of moderate exercise in patients with inflammatory bowel disease or functional gastrointestinal disorders, the safety of more strenuous exercise has not been established. Conclusions Strenuous exercise has a major reversible impact on gastrointestinal integrity and function of healthy populations. The safety and health implications of prolonged strenuous exercise in patients with chronic gastrointestinal diseases/disorders, while hypothetically worrying, has not been elucidated and requires further investigation.

Exercise-Induced Gastrointestinal Symptoms in Endurance Sports: A Review of Pathophysiology, Symptoms, and Nutritional Management

Article

Full-text available

Sep 2023

Strenuous exercise can be associated with “Exercise Induced Gastrointestinal Syndrome” (Ex-GIS), a clinical condition characterized by a series of gastrointestinal (GI) disturbances that may impact the physical and psychological performance of athletes. The pathophysiology comprises multi-factorial interactions between the GI tract and the circulatory, immune, enteric, and central nervous systems. There is considerable evidence for increases in the indices of intestinal damage, permeability, and endotoxemia associated with impaired gastric emptying, slowing of small intestinal transit, and malabsorption of nutrients. Heat stress and racing mode seem to exacerbate these GI disturbances. GI symptomatology that derives from strenuous exercise is similar to that of IBS and other GI functional disorders defined in the Rome IV Criteria. To manage Ex-GIS, the exercise modality, state of dehydration, environmental temperature, concomitant therapies, and self-managed diet should be evaluated, and if risk elements are present, an attempt should be made to modify them. Multiple strategies can be successively adopted to manage Ex-GIS. Nutritional and behavioral interventions appear to be the principal ones to avoid symptoms during the exercise. The aim of this review will be to explore the pathophysiology, clinical aspect, and current literature on behavioral and nutritional strategies to manage Ex-GIS, regarding a gluten-free diet and low-fermentable oligo-, di-, and mono-saccharides and polyols (FODMAP) diet.

An Exploratory Study Investigating the Prevalence of Gastrointestinal Symptoms in Collegiate Division I American Football Athletes

Article

Full-text available

Jul 2023
Int J Environ Res Publ Health

Gastrointestinal (GI) symptoms may limit performance, but their prevalence and impact among team sports athletes is not well-documented. The objective of this study was to examine the prevalence of GI symptoms in a small sample of collegiate DI American football athletes, using a survey including the Gastrointestinal Symptoms Ratings Scale (GSRS). Forty-six athletes responded to the survey and reported scores for the 15-question GSRS with additional questions about dietary habits and supplement use. A total of 44 athletes were included in the study (45% of the current roster, age: 20.7 ± 1.7 years, 50% Afro-American or black, 39% skill position, 18% NSAIDs use, and 41% reporting protein supplement use); approximately half of the athletes (52%) reported experiencing GI complaints during exercise. Two-thirds of the athletes (61%) reported at least one or more GI symptoms in general, and 50% reported at least four moderate complaints. Seven athletes (16%) reported ≥2 severe GI symptoms with 5–13 moderate complaints. The most reported symptom was stomach pain (39%, n = 17), followed by hunger pain (36%, n = 16). Athletes reporting the use of protein supplements reported a higher GSRS score (22.0 and interquartile range (IQR) 17.0–31.8) vs. athletes not reporting protein use (15.0 and IQR 15.0–19.3), p = 0.001. Most athletes surveyed reported experiencing GI symptoms. A small group of these athletes reported multiple, varied, and severe symptoms that were associated with self-reported protein supplement use. In conclusion, the number of complaints varied among athletes, confirming the value of integrating the GSRS for screening purposes, and the expected need for individual dietary treatment approaches.

The Effect of Gut-Training and Feeding-Challenge on Markers of Gastrointestinal Status in Response to Endurance Exercise: A Systematic Literature Review

Article

Full-text available

Apr 2023
SPORTS MED

Background Nutrition during exercise is vital in sustaining prolonged activity and enhancing athletic performance; however, exercise-induced gastrointestinal syndrome (EIGS) and exercise-associated gastrointestinal symptoms (Ex-GIS) are common issues among endurance athletes. Despite this, there has been no systematic assessment of existing trials that examine the impact of repetitive exposure of the gastrointestinal tract to nutrients before and/or during exercise on gastrointestinal integrity, function, and/or symptoms. Objective This systematic literature review aimed to identify and synthesize research that has investigated the impact of ‘gut-training’ or ‘feeding-challenge’ before and/or during exercise on markers of gastrointestinal integrity, function, and symptoms. Methods Five databases (Ovid MEDLINE, EMBASE, CINAHL Plus, Web of Science Core Collection, and SPORTDiscus) were searched for literature that focused on gut-training or feeding-challenge before and/or during exercise that included EIGS and Ex-GIS variables. Quality assessment was conducted in duplicate and independently using the Cochrane Collaboration’s risk-of-bias (RoB 2) tool. Results Overall, 304 studies were identified, and eight studies were included after screening. Gut-training or feeding-challenge interventions included provision of carbohydrates only (n = 7) in various forms (e.g., gels or liquid solutions) during cycling or running, or carbohydrate with protein (n = 1) during intermittent exercise, over a varied duration (4–28 days). Gut discomfort decreased by an average of 47% and 26% with a 2-week repetitive carbohydrate feeding protocol (n = 2) and through repeated fluid ingestion over five trials (n = 1), respectively. Repetitive carbohydrate feeding during exercise for 2 weeks resulted in the reduction of carbohydrate malabsorption by 45–54% (n = 2), but also led to no significant change (n = 1). The effect of gut-training and feeding-challenges on the incidence and severity of Ex-GIS were assessed using different tools (n = 6). Significant improvements in total, upper, and lower gastrointestinal symptoms were observed (n = 2), as well as unclear results (n = 4). No significant changes in gastric emptying rate (n = 2), or markers of intestinal injury and permeability were found (n = 3). Inconclusive results were found in studies that investigated plasma inflammatory cytokine concentration in response to exercise with increased carbohydrate feeding (n = 2). Conclusions Overall, gut-training or feeding-challenge around exercise may provide advantages in reducing gut discomfort, and potentially improve carbohydrate malabsorption and Ex-GIS, which may have exercise performance implications.

Carbohydrate knowledge, beliefs, and intended practices, of endurance athletes who report exercise-associated gastrointestinal symptoms

Article

Full-text available

Apr 2023

This study aimed to explore carbohydrate (CHO) knowledge, beliefs, and intended practices of endurance athletes who experience exercise-associated gastrointestinal symptoms (Ex-GIS) compared to those without Ex-GIS. A validated online questionnaire was completed by endurance athletes ( n = 201) participating in >60 min of exercise that present with Ex-GIS ( n = 137) or without ( n = 64). Descriptive statistics were used for parametric and non-parametric data with appropriate significance tests. Associations between categorical data were assessed by Chi-square analysis, and post-hoc Bonferroni tests were applied when significant. A content analysis of open-ended responses was grouped into themes, and quantitative statistics were applied. Participants included runners ( n = 114, 57%), triathletes ( n = 43, 21%) and non-running sports ( n = 44, 21%) who participate in recreational competitive ( n = 74, 37%), recreational non-competitive ( n = 64, 32%), or competitive regional, national, or international levels ( n = 63, 31%). Athletes correctly categorized CHO ( x̄ = 92–95%) and non-CHO ( x̄ = 88–90%) food and drink sources. On a Likert scale of 1 (strongly disagree) to 5 (strongly agree) athletes typically agree or strongly agree that consuming CHO around key training sessions and competitions enhances athletic performance [median = 4 (IQR, 4–5)], and they intend to consume more CHO around exercise [median = 3 (IQR, 2–3)]. No differences in beliefs and intentions were found among athletes with or without Ex-GIS. To enhance athletic performance, most endurance athletes intend to consume more CHO around exercise. Adequate knowledge of CHO-containing food sources was apparent; however, specific CHO ingestion practices remain to be verified.

Reliability of pathophysiological markers reflective of exercise-induced gastrointestinal syndrome (EIGS) in response to 2-h high-intensity interval exercise: A comprehensive methodological efficacy exploration

Article

Full-text available

Feb 2023

The study aimed to determine the test-retest reliability of exercise-induced gastrointestinal syndrome (EIGS) biomarkers, and assess the association of pre-exercise short chain fatty acid (SCFA) concentration with these biomarkers in response to prolonged strenuous exercise. Thirty-four participants completed 2 h of high-intensity interval training (HIIT) on two separate occasions with at least 5-days washout. Blood samples were collected pre- and post-exercise, and analysed for biomarkers associated with EIGS [i.e., cortisol, intestinal fatty-acid binding protein (I-FABP), sCD14, lipopolysaccharide binding protein (LBP), leukocyte counts, in-vitro neutrophil function, and systemic inflammatory cytokine profile]. Fecal samples were collected pre-exercise on both occasions. In plasma and fecal samples, bacterial DNA concentration was determined by fluorometer quantification, microbial taxonomy by 16S rRNA amplicon sequencing, and SCFA concentration by gas-chromatography. In response to exercise, 2 h of HIIT modestly perturbed biomarkers indicative of EIGS, including inducing bacteremia (i.e., quantity and diversity). Reliability analysis using comparative tests, Cohen’s d, two-tailed correlation, and intraclass correlation coefficient (ICC) of resting biomarkers presented good-to-excellent for IL-1ra (r = 0.710, ICC = 0.92), IL-10 (r = 0.665, ICC = 0.73), cortisol (r = 0.870, ICC = 0.87), and LBP (r = 0.813, ICC = 0.76); moderate for total (r = 0.839, ICC = 0.44) and per cell (r = 0.749, ICC = 0.54) bacterially-stimulated elastase release, IL-1β (r = 0.625, ICC = 0.64), TNF-α (r = 0.523, ICC = 0.56), I-FABP (r = 0.411, ICC = 0.21), and sCD14 (r = 0.409, ICC = 0.38), plus fecal bacterial α-diversity; and poor for leukocyte (r = 0.327, ICC = 0.33) and neutrophil (r = 0.352, ICC = 0.32) counts. In addition, a medium negative correlation was observed between plasma butyrate and I-FABP (r = −0.390). The current data suggest a suite of biomarkers should be used to determine the incidence and severity of EIGS. Moreover, determination of plasma and/or fecal SCFA may provide some insight into the mechanistic aspects of EIGS instigation and magnitude in response to exercise.

Effect of prebiotics, probiotics, and synbiotics on gastrointestinal outcomes in healthy adults and active adults at rest and in response to exercise—A systematic literature review

Article

Full-text available

Dec 2022

Introduction A systematic literature search was undertaken to assess the impact of pre-, pro-, and syn-biotic supplementation on measures of gastrointestinal status at rest and in response to acute exercise. Methods Six databases (Ovid MEDLINE, EMBASE, Cinahl, SportsDISCUS, Web of Science, and Scopus) were used. Included were human research studies in healthy sedentary adults, and healthy active adults, involving supplementation and control or placebo groups. Sedentary individuals with non-communicable disease risk or established gastrointestinal inflammatory or functional diseases/disorders were excluded. Results A total of n = 1,204 participants were included from n = 37 papers reported resting outcomes, and n = 13 reported exercise-induced gastrointestinal syndrome (EIGS) outcomes. No supplement improved gastrointestinal permeability or gastrointestinal symptoms (GIS), and systemic endotoxemia at rest. Only modest positive changes in inflammatory cytokine profiles were observed in n = 3/15 studies at rest. Prebiotic studies ( n = 4/5) reported significantly increased resting fecal Bifidobacteria, but no consistent differences in other microbes. Probiotic studies ( n = 4/9) increased the supplemented bacterial species-strain. Only arabinoxylan oligosaccharide supplementation increased total fecal short chain fatty acid (SCFA) and butyrate concentrations. In response to exercise, probiotics did not substantially influence epithelial injury and permeability, systemic endotoxin profile, or GIS. Two studies reported reduced systemic inflammatory cytokine responses to exercise. Probiotic supplementation did not substantially influence GIS during exercise. Discussion Synbiotic outcomes resembled probiotics, likely due to the minimal dose of prebiotic included. Methodological issues and high risk of bias were identified in several studies, using the Cochrane Risk of Bias Assessment Tool. A major limitation in the majority of included studies was the lack of a comprehensive approach of well-validated biomarkers specific to gastrointestinal outcomes and many included studies featured small sample sizes. Prebiotic supplementation can influence gut microbial composition and SCFA concentration; whereas probiotics increase the supplemented species-strain, with minimal effect on SCFA, and no effect on any other gastrointestinal status marker at rest. Probiotic and synbiotic supplementation does not substantially reduce epithelial injury and permeability, systemic endotoxin and inflammatory cytokine profiles, or GIS in response to acute exercise.

The effects of collagen peptides on exercise-induced gastrointestinal stress: a randomized, controlled trial

Article

Full-text available

Nov 2022
EUR J NUTR

Purpose We examined the effects of collagen peptides (CP) supplementation on exercise-induced gastrointestinal (GI) stress. Methods In a randomized, crossover design, 20 volunteers (16 males: $$\dot{V}$$ V ˙ O 2max , 53.4 ± 5.9 ml·kg ⁻¹ ) completed 3 trials: a non-exercise rest trial, with no supplement (REST) and then an exercise trial with CP (10 g·day ⁻¹ ) or placebo control (CON) supplements, which were consumed for 7 days prior to, and 45 min before, a 70 min run at 70–90% of $$\dot{V}$$ V ˙ O 2max . Outcome measures included urinary lactulose and rhamnose (L/R), intestinal fatty acid binding protein (I-FABP), lipopolysaccharide (LPS), anti-LPS antibody, monocyte-chemoattractant protein-1 (MCP-1), interleukin (IL) 6 and 8, cortisol, alkaline phosphatase (ALP) (measured pre, 10 min post and 2 h post) and subjective GI symptoms. Results There were no differences in heart rate, perceived exertion, thermal comfort, or core temperature during exercise in the CP and CON trials (all P > 0.05). I-FABP was higher in CP (2538 ± 1221 pg/ml) and CON (2541 ± 766 pg/ml) vs. REST 2 h post (1893 ± 1941 pg/ml) (both P < 0.05). LPS increased in CON vs. REST 2 h post (+ 71.8 pg/ml; P < 0.05). Anti-LPS antibody decreased in CON and CP vs. REST at post (both P < 0.05). There were no differences in MCP-1, IL-6, and IL-8 between the CP and CON trials (all P > 0.05), and no differences in L/R or GI symptoms between CON and CP (all P > 0.05). Conclusion Collagen peptides did not modify exercise-induced changes in inflammation, GI integrity or subjective GI symptoms but LPS was higher in CON 2 h post-exercise and thus future studies may be warranted.

An exploratory study of the management strategies reported by endurance athletes with exercise-associated gastrointestinal symptoms

Article

Full-text available

Nov 2022

This exploratory study investigated endurance athletes self-reported exercise-associated gastrointestinal symptoms (Ex-GIS) and associated strategies to manage symptomology. Adult endurance athletes with a history of Ex-GIS (n = 137) participating in events ≥ 60 min completed an online validated questionnaire. Respondents included runners (55%, n = 75), triathletes (22%, n = 30), and non-running sports (23%, n = 32), participating at a recreationally competitive (37%, n = 51), recreationally non-competitive (32%, n = 44), and competitive regional/national/international (31%, n = 42) levels. Athletes identified when Ex-GIS developed most frequently either around training (AT), around competitions (AC), or equally around both training (ET) and competitions (EC). Athletes reported the severity of each symptom before, during, and after exercise. Athletes predominantly categorized Ex-GIS severity as mild (< 5/10) on a 0 (no symptoms) to 10 (extremely severe symptoms) visual analog symptomology scale. The Friedman test and post hoc analysis with Wilcoxon signed rank test was conducted with a Bonferroni correction applied to determine differences between repeated measures. The only severe symptom of significance was the urge to defecate during training in the ET group (Z = –0.536, p = 0.01). Ex-GIS incidence was significantly higher during training and competitions in all categories. A content review of self-reported strategies (n = 277) to reduce Ex-GIS indicated popular dietary strategies were dietary fiber reduction (15.2%, n = 42), dairy avoidance (5.8%, n = 16), and a low fermentable oligosaccharides, monosaccharides, and polyols (FODMAP) diet (5.4%, n = 15). In contrast, non-dietary strategies included the use of medications (4.7%, n = 13) and relaxation/meditation (4.0%, n = 11). On a Likert scale of 1–5, the most successful dietary strategies implemented were dietary fiber reduction (median = 4, IQR = 4, 5), low FODMAP diets (median = 4, IQR = 4, 5), dairy-free diets (median = 4, IQR = 4, 5), and increasing carbohydrates (median = 4, IQR = 3, 4). Accredited practicing dietitians were rated as the most important sources of information for Ex-GIS management (n = 29). Endurance athletes use a variety of strategies to manage their Ex-GIS, with dietary manipulation being the most common.

The increase in core body temperature in response to exertional-heat stress can predict exercise-induced gastrointestinal syndrome

Article

May 2023

Purpose Utilising metadata from existing exertional and exertional-heat stress studies, the study aimed to determine if the exercise-associated increase in core body temperature can predict the change in exercise-induced gastrointestinal syndrome (EIGS) biomarkers and exercise-associated gastrointestinal symptoms (Ex-GIS). Method Endurance-trained individuals completed 2h of running exercise in temperate (21.2-30.0°C) to hot (35.0-37.2°C) ambient conditions (n=132 trials). Blood samples were collected pre- and post-exercise to determine the change in gastrointestinal integrity biomarkers and systemic inflammatory cytokines. Physiological and thermoregulatory strain variables were assessed every 10-15min during exercise. The strength of the linear relationship between maximal (M-Tre) and change (Δ Tre) in rectal temperature and EIGS variables was determined via Spearman’s rank correlation coefficients. While the strength of prediction was determined via simple and multiple linear regression analyses dependent on screened EIGS and Ex-GIS confounding factors. Results Significant positive correlations between Tre maximum (M-Tre) and change (Δ Tre) with I-FABP (rs=0.434, p<0.001; and rs=0.305, p<0.001; respectively), sCD14 (rs=0.358, p<0.001; and rs=0.362, p<0.001), systemic inflammatory response profile (SIR-Profile) (p<0.001), and total Ex-GIS (p< 0.05) were observed. M-Tre and Δ Tre significantly predicted (adjusted R²) magnitude of change in I-FABP (R²(2,123)=0.164, p<0.001; and R²(2,119)=0.058, p=0.011; respectively), sCD14 (R²(2,81)=0.249, p<0.001; and R²(2,77)=0.214, p<0.001), SIR-Profile (p<0.001) and total Ex-GIS (p<0.05). Conclusion Strong to weak correlations were observed between M-Tre and Δ Tre with plasma concentrations of I-FABP, sCD14, SIR-Profile, and Ex-GIS in response to exercise. M-Tre and Δ Tre can predict the magnitude of these EIGS variables and Ex-GIS in response to exercise.

Determining the relationship between fiber consumption and physical activity and bowel habits in office workers

Article

Full-text available

Apr 2023

It is thought that bowel transit time decreases with reduced fiber consumption and physical activity in office workers who lead a sedentary life. The consumption of plant-based diets is decreasing due to technological advances, which leads to a decrease in dietary fiber consumption. Furthermore, officer workers have low physical activity levels. Therefore, the aim of the present study was to determine the relationship between fiber intake, physical activity and bowel habits in office workers. A total of 100 office workers with a mean age of 33.25±7.28 were included in this cross-sectional study. A questionnaire consisting of 29 questions was prepared by the researchers. The questions on bowel habits were prepared based on the Rome III criteria and the Bristol scale was used as the diagnostic criteria of intestinal diseases. It was found that 50% of participants with low fiber consumption and 91.7% of those with high fiber consumption defecate once a day (p

Actividad física, salud y calidad de vida

Book

Aug 2023

Se realizó un estudio multidisciplinario que aborda la importancia de la actividad física en diversos contextos de salud y bienestar humano, con un enfoque particular en la inclusión de personas con discapacidades. Utilizando una combinación de teorías como la Teoría del Comportamiento Planificado y la Teoría Social Cognitiva, se exploran los vínculos entre la actividad física y los sistemas del organismo humano, las enfermedades crónicas, la salud mental, el rendimiento académico, la estética corporal, el envejecimiento saludable, la calidad de vida, y la nutrición. El método emplea una revisión exhaustiva de la literatura y un análisis crítico de las prácticas actuales. Los resultados destacan la necesidad de superar diversas barreras, como las físicas, psicológicas, y económicas, para lograr una participación inclusiva en la actividad física. Las principales conclusiones enfatizan la importancia de la colaboración comunitaria, las tecnologías y herramientas de apoyo, y las políticas inclusivas para fomentar la actividad física en todas las poblaciones.

The Effect of Pre-Exercise Hyperhydration on Exercise Performance, Physiological Outcomes and Gastrointestinal Symptoms: A Systematic Review

Article

Full-text available

Jul 2023
SPORTS MED

Background Fluid loss during prolonged exercise in hot conditions poses thermoregulatory and cardiovascular challenges for athletes that can lead to impaired performance. Pre-exercise hyperhydration using nutritional aids is a strategy that may prevent or delay the adverse effects of dehydration and attenuate the impact of heat stress on exercise performance. Objectives The aim of this systematic review was to examine the current literature to determine the effect of pre-exercise hyperhydration on performance, key physiological responses and gastrointestinal symptoms. Methods English language, full-text articles that compared the intervention with a baseline or placebo condition were included. An electronic search of Medline Complete, SPORTDiscus and Embase were used to identify articles with the final search conducted on 11 October 2022. Studies were assessed using the American Dietetic Association Quality Criteria Checklist. Results Thirty-eight studies involving 403 participants ( n = 361 males) were included in this review ( n = 22 assessed exercise performance or capacity). Two studies reported an improvement in time-trial performance (range 5.7–11.4%), three studies reported an improvement in total work completed (kJ) (range 4–5%) and five studies reported an increase in exercise capacity (range 14.3–26.2%). During constant work rate exercise, nine studies observed a reduced mean heart rate (range 3–11 beats min ⁻¹ ), and eight studies reported a reduced mean core temperature (range 0.1–0.8 °C). Ten studies reported an increase in plasma volume (range 3.5–12.6%) compared with a control. Gastrointestinal symptoms were reported in 26 studies, with differences in severity potentially associated with factors within the ingestion protocol of each study (e.g. treatment, dose, ingestion rate). Conclusions Pre-exercise hyperhydration may improve exercise capacity during constant work rate exercise due to a reduced heart rate and core temperature, stemming from an acute increase in plasma volume. The combination of different osmotic aids (e.g. glycerol and sodium) may enhance fluid retention and this area should continue to be explored. Future research should utilise valid and reliable methods of assessing gastrointestinal symptoms. Furthermore, studies should investigate the effect of hyperhydration on different exercise modalities whilst implementing a strong level of blinding. Finally, females are vastly underrepresented, and this remains a key area of interest in this area.

The Health Belief Model and the Gluten-Free Diet: Are Gluten-Free Products Really Beneficial in Athlete Diets?

Article

Full-text available

Jun 2023

People often think gluten-free products are healthier. This idea has been a source of motivation for many consumers, including athletes. With the growing popular perception that gluten-free foods are healthier, whether this diet is actually beneficial has had to be questioned. In the study, on the basis of the Health Belief Model, it was evaluated how the gluten-free diet was preferred among the athletes. With this study, it is aimed to contribute to the formation of awareness in athletes on this issue. Scientific publications published so far have been examined with a systematic literature search. 45 studies between the years 2012-2022 in Web of Science, Scopus and TR Index databases have been examined. “Are Gluten-Free Products Really Beneficial in Athlete Diets?” in all of the reviewed publications. The answer to the research question was sought. The data analyzed with the MAXQDA 2020 qualitative data analysis program were classified and interpreted by the content analysis method. The study was designed according to the ENTREQ control guideline. As a result of the sources examined, it has been determined that a gluten-free diet facilitates digestion, lowers cholesterol levels and reduces cardiovascular risks. However, it has been observed that the body is deficient in meeting the nutrients it needs. Studies conducted in various countries have shown that gluten-free products have poor content, especially in terms of protein and iron content that athletes need. Most of the obtained publications were compilation type. However, it is thought that case studies to be conducted with athletes who eat gluten-free in future studies will allow to discuss the subject from a different aspect.

The effect of physical activity on gut microbiota. A review

Article

Full-text available

Apr 2023

This review examines how physical activity can modulate the gut microbiota, taking into account the training intensity used, the value of the load and the age group studied. The aim of the study is to show the significant interaction between exercise and its effects on the gut microbiota. Many of the studies we analysed showed an interesting correlation between the physical activity undertaken and the change in biodiversity and taxon representation, so we concluded that exercise can significantly modulate the composition of the gut microbiome. This also works the other way around, as doing too much intense and taxing exercise can lead to so-called intestinal dysbiosis, which promotes inflammatory reactions and other unfavourable metabolic consequences. Therefore, in this review, we have analysed the latest and most interesting body of literature oscillating around the complex relationship between the movement undertaken and its impact on the microbiome.

Resveratrol attenuated high intensity exercise training-induced inflammation and ferroptosis via Nrf2/FTH1/GPX4 pathway in intestine of mice

Article

Apr 2023

Background: Moderate exercise has beneficial effects for human health and is helpful for the protection against several diseases. However, high intensity exercise training caused gastrointestinal syndrome. Resveratrol, a plant extract, plays a vital role in protecting various organs. However, whether resveratrol protected mice against high intensity exercise training-induced intestinal damage remains unclear. In this study, our objective was to investigate the protective effects and mechanism of resveratrol in high intensity exercise training-treated mice. Methods: Mice were treated with swimming exercise protocol and/or resveratrol (15 mg/kg/day) for 28 consecutive days. Then, the mice were sacrificed, and a series of evaluation indicators, including inflammatory factors and intestinal permeability of the gut, were measured based on this model. The expressions of inflammatory factors (tumor necrosis factor (TNF)-α; interferon (IFN)-γ, interleukin (IL)-6 and IL-10), oxidative stress (Nrf2, glutathione (GSH), hydrogen peroxide (H2 O2), catalase (CAT) and malondialdehyde(MDA)), intestinal barrier (gut permeability, ZO-1, Occludin and Claudin-1 as well as ferroptosis (Fe2+, Fe3+, SLC7A11, glutathioneperoxidase 4 (GPX4) and ferritin heavy chain 1 (FTH1)) were measured, respectively. Results: High intensity exercise training induced colon damage, manifested as inflammation (increased TNF-α, IFN-γ and IL-6 concentrations, and decreased IL-10 concentration), oxidative stress (the increase of H2O2 and MDA concentration, and the reduced CAT and GSH activities), intestinal barrier injury (increased gut permeability and intestinal fatty-acid binding protein concentration,and inhibited ZO-1, Occludin and Claudin-1 expressions) and ferroptosis (the increased of Fe2+ and Fe3+ concentrations, and suppressed phosphorylated Nrf2, SLC7A11, GPX4 and FTH1), which was relieved by resveratrol treatment in mice. Discussion: Resveratrol attenuated high intensity exercise training-induced inflammation and ferroptosis through activating Nrf2/ FTH1/GPX4 pathway in mouse colon, which providing new ideas for the prevention and treatment of occupational disease in athlete.

Pterostilbene Attenuates High-Intensity Swimming Exercise-Induced Glucose Absorption Dysfunction Associated with the Inhibition of NLRP3 Inflammasome-Induced IECs Pyroptosis

Article

Full-text available

Apr 2023

The study investigated the effect of pterostilbene (PTE) on intestinal glucose absorption and its underlying mechanisms in high-intensity swimming exercise (HISE)-treated mice. Male C57BL/6 mice were treated with PTE for 4 weeks and performed high-intensity swimming training in the last week. Intestinal epithelial cells (IECs) were pretreated with 0.5 and 1.0 μM PTE for 24 h before being incubated in hypoxia/reoxygenation condition. Intestinal glucose absorption was detected by using an oral glucose tolerance test and d-xylose absorption assay, and the levels of factors related to mitochondrial function and pyroptosis were measured via western blot analyses, cell mito stress test, and quantitative real-time polymerase chain reaction. In vivo and in vitro, the results showed that PTE attenuated HISE-induced intestinal glucose absorption dysfunction and pyroptosis in mice intestine. Moreover, PTE inhibited NLRP3 inflammasome and the mitochondrial homeostasis as well as the ROS accumulation in IEC in vitro. Additionally, knockdown of SIRT3, a major regulator of mitochondria function, by siRNA or inhibiting its activity by 3-TYP abolished the effects of PTE on pyroptosis, mitochondrial homeostasis, and ROS generation of IEC in vitro. Our results revealed that PTE could alleviate HISE-induced intestinal glucose absorption dysfunction associated with the inhibition of NLRP3 inflammasome-induced IECs pyroptosis.

Colostrum and Lactoferrin Protect against Side Effects of Therapy with Antibiotics, Anti-inflammatory Drugs and Steroids, and Psychophysical Stress: A Comprehensive Review

Article

Full-text available

Mar 2023

In this article, we review the benefits of applying bovine colostrum (BC) and lactoferrin (LF) in animal models and clinical trials that include corticosteroid application and psychic stress, treatment with non-steroid anti-inflammatory drugs (NSAIDs) and antibiotics. A majority of the reported investigations were performed with native bovine or recombinant human LF, applied alone or in combination with probiotics, as nutraceutics and diet supplements. Apart from reducing adverse side effects of the applied therapeutics, BC and LF augmented their efficacy and improved the wellness of patients. In conclusion, LF and complete native colostrum, preferably administered with probiotic bacteria, are highly recommended for inclusion in therapeutic protocols in NSAIDs and corticosteroid anti-inflammatory, as well as antibiotic, therapies. These colostrum-based products can also be of value for individuals subjected to prolonged psychophysical stress (mediated by endogenous corticosteroids), especially at high ambient temperatures (soldiers and emergency services), as well as physically active people and training athletes. They are also recommended for patients during recovery from trauma and surgery, which are always associated with severe psychophysical stress.

Exercise Perceptions and Experiences in Adults With Crohn’s Disease Following a Combined Impact and Resistance Training Program: A Qualitative Study

Article

Full-text available

Mar 2023

Background Exercise is increasingly being recognised to counteract specific complications of Crohn’s disease. The aim of this study was to explore exercise experiences and perceptions after engaging in a combined impact and resistance training programme, involving both intervention and control group viewpoints. Methods: S emi-structured telephone interviews, involving a convenience sample of participants with Crohn’s disease (n=41; aged 49.1±12 years) were undertaken up to 6 weeks following completion of the programme. Data were analysed using thematic analysis. Results Four overarching themes emerged, along with 11 subthemes: 1) Lack of confidence and knowledge, fears surrounding physical ability and symptoms, coupled with issues not addressed as part of the healthcare pathway played a part in transitioning to inactivity; 2) Improvements in strength, mental well-being, physical fitness, fatigue, abdominal and joint pain, comorbidities, and self-management strategies were amongst the reported benefits of exercise participation; 3) Seeing progress, goal setting, enjoyment and a peer-led programme receiving support and advice increased motivation. Whereas work-related tiredness, other commitments, and self-directed exercise were reported as exercise barriers; 4) The intervention design was well received and the journey from start to finish was positively discussed, important considerations for future interventions and implementation strategies. Conclusions The study yielded novel perceptions on the transition to inactivity following receiving a diagnosis, physical and psychological benefits accruing from the intervention, and views on programme design. Information that will provide an essential step in the development of implementing exercise guidelines into the clinical pathway and supporting individuals with self-management options.

Effects of high-/low-temperature and high-altitude hypoxic environments on gut microbiota of sports people: A retrospective analysis

Article

Full-text available

Mar 2023

As an invisible “endocrine organ”, gut microbiota is widely involved in the regulation of nervous system, endocrine system, circulatory system, and digestive system. It is also closely related to host health and the occurrence of many chronic diseases. Relevant literature shows that high temperature, low temperature, and high-altitude hypoxia may have negative effects on commensal microorganisms. The stimulation of exercise may aggravate this reaction, which is related to the occurrence of exercise-induced fever and gastrointestinal and respiratory diseases. The intervention of probiotics can alleviate the above problems to a certain extent. Therefore, this paper takes exercise in a special environment as the starting point, deeply analyses the intervention effect and potential mechanism of probiotics, and provides the theoretical basis and reference for follow-up research and application of probiotics in sports science.

Intensity-specific considerations for exercise for patients with inflammatory bowel disease

Article

Full-text available

Feb 2023

The rising prevalence of inflammatory bowel disease (IBD) necessitates that patients be given increased access to cost-effective interventions to manage the disease. Exercise is a non-pharmacologic intervention that advantageously affects clinical aspects of IBD, including disease activity, immune competency, inflammation, quality of life, fatigue, and psychological factors. It is well established that exercise performed at low-to-moderate intensity across different modalities manifests many of these diseased-related benefits while also ensuring patient safety. Much less is known about higher-intensity exercise. The aim of this review is to summarize findings on the relationship between strenuous exercise and IBD-related outcomes. In healthy adults, prolonged strenuous exercise may unfavorably alter a variety of gastrointestinal (GI) parameters including permeability, blood flow, motility, and neuro-endocrine changes. These intensity- and gut-specific changes are hypothesized to worsen IBD-related clinical presentations such as diarrhea, GI bleeding, and colonic inflammation. Despite this, there also exists the evidence that higher-intensity exercise may positively influence microbiome as well as alter the inflammatory and immunomodulatory changes seen with IBD. Our findings recognize that safety for IBD patients doing prolonged strenuous exercise is no more compromised than those doing lower-intensity work. Safety with prolonged, strenuous exercise may be achieved with adjustments including adequate hydration, nutrition, drug avoidance, and careful attention to patient history and symptomatology. Future work is needed to better understand this intensity-dependent relationship so that guidelines can be created for IBD patients wishing to participate in high-intensity exercise or sport.

Differential Effects of Oligosaccharides, Antioxidants, Amino Acids and PUFAs on Heat/Hypoxia-Induced Epithelial Injury in a Caco-2/HT-29 Co-Culture Model

Article

Full-text available

Jan 2023
INT J MOL SCI

(1) Exposure of intestinal epithelial cells to heat and hypoxia causes a (heat) stress response, resulting in the breakdown of epithelial integrity. There are indications that several categories of nutritional components have beneficial effects on maintaining the intestinal epithelial integrity under stress conditions. This study evaluated the effect of nine nutritional components, including non-digestible oligosaccharides (galacto-oligosaccharides (GOS), fructo-oligosaccharides (FOS), chitosan oligosaccharides (COS)), antioxidants (α-lipoic acid (ALA), resveratrol (RES)), amino acids (l-glutamine (Glu), l-arginine (Arg)) and polyunsaturated fatty acids (PUFAs) (docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA)), on heat/hypoxia-induced epithelial injury. (2) Two human colonic cell lines, Caco-2 and HT-29, were co-cultured and pre-treated with the nutritional components for 48 h. After pre-treatment, the cells were exposed to heat/hypoxia (42 °C, 5% O2) for 2 h. Epithelial integrity was evaluated by measuring trans-epithelial electrical resistance (TEER), paracellular Lucifer Yellow (LY) permeability, and tight junction (TJ) protein expression. Heat stress and oxidative stress levels were evaluated by determining heat-shock protein-70 (HSP-70) expression and the concentration of the lipid peroxidation product malondialdehyde (MDA). (3) GOS, FOS, COS, ALA, RES, Arg, and EPA presented protective effects on epithelial damage in heat/hypoxia-exposed Caco-2/HT-29 cells by preventing the decrease in TEER, the increase in LY permeability, and/or decrease in TJ proteins zonula occludens-1 (ZO-1) and claudin-3 expression. COS, RES, and EPA demonstrated anti-oxidative stress effects by suppressing the heat/hypoxia-induced MDA production, while Arg further elevated the heat/hypoxia-induced increase in HSP-70 expression. (4) This study indicates that various nutritional components have the potential to counteract heat/hypoxia-induced intestinal injury and might be interesting candidates for future in vivo studies and clinical trials in gastrointestinal disorders related to heat stress and hypoxia.

The Impact of Heat Acclimation on Gastrointestinal Function following Endurance Exercise in a Hot Environment

Article

Full-text available

Jan 2023

To determine the effects of heat acclimation on gastrointestinal (GI) damage and the gastric emptying (GE) rate following endurance exercise in a hot environment. Fifteen healthy men were divided into two groups: endurance training in hot (HOT, 35 °C, n = 8) or cool (COOL, 18 °C, n = 7) environment. All subjects completed 10 days of endurance training (eight sessions of 60 min continuous exercise at 50% of the maximal oxygen uptake (V·O2max). Subjects completed a heat stress exercise tests (HST, 60 min exercise at 60% V·O2max) to evaluate the plasma intestinal fatty acid-binding protein (I-FABP) level and the GE rate following endurance exercise in a hot environment (35 °C) before (pre-HST) and after (post-HST) the training period. We assessed the GE rate using the 13C-sodium acetate breath test. The core temperature during post-HST exercise decreased significantly in the HOT group compared to the pre-HST (p = 0.004) but not in the COOL group. Both the HOT and COOL groups showed exercise-induced plasma I-FABP elevations in the pre-HST (p = 0.002). Both groups had significantly attenuated exercise-induced I-FABP elevation in the post-HST. However, the reduction of exercise-induced I-FABP elevation was not different significantly between both groups. GE rate following HST did not change between pre- and post-HST in both groups, with no significant difference between two groups in the post-HST. Ten days of endurance training in a hot environment improved thermoregulation, whereas exercise-induced GI damage and delay of GE rate were not further attenuated compared with training in a cool environment.

Dihydromyricetin Attenuates High-Intensity Exercise-Induced Intestinal Barrier Dysfunction Associated with the Modulation of the Phenotype of Intestinal Intraepithelial Lymphocytes

Article

Full-text available

Dec 2022
INT J MOL SCI

Background: Exercise-induced gastrointestinal syndrome (GIS) has symptoms commonly induced by strenuous sports. The study aimed to determine the effect of dihydromyricetin (DHM) administration on high-intensity exercise (HIE)-induced intestinal barrier dysfunction and the underlying mechanism involved with intestinal intraepithelial lymphocytes (IELs). Methods: The HIE model was established with male C57BL/6 mice using a motorized treadmill for 2 weeks, and DHM was given once a day by oral gavage. After being sacrificed, the small intestines of the mice were removed immediately. Results: We found that DHM administration significantly suppressed HIE-induced intestinal inflammation, improved intestinal barrier integrity, and inhibited a HIE-induced increase in the number of IELs and the frequency of CD8αα+ IELs. Meanwhile, several markers associated with the activation, gut homing and immune functions of CD8αα+ IELs were regulated by DHM. Mechanistically, luciferase reporter assay and molecular docking assay showed DHM could activate the aryl hydrocarbon receptor (AhR). Conclusions: These data indicate that DHM exerts a preventive effect against HIE-induced intestinal barrier dysfunction, which is associated with the modulation of the quantity and phenotype of IELs in the small intestine. The findings provide a foundation to identify novel preventive strategies based on DHM supplementation for HIE-induced GIS.

Greater plasma essential amino acids and lower 3-methylhistidine with higher protein intake during endurance training: a randomised control trial

Article

Full-text available

Dec 2022
AMINO ACIDS

Endurance exercise alters amino acid (AA) metabolism that necessitates greater AA intake in the post exercise recovery period to support recovery. Thus, daily AA ingestion during a period of endurance training may affect the metabolically active plasma free AA pool, which is otherwise maintained during periods of inadequate protein intake by the breakdown of skeletal muscle proteins. Nine endurance-trained males completed a 4-day running protocol (20 km, 5 km, 10 km and 20 km on days 1–4, respectively) on three occasions with a controlled diet providing different protein intakes [0.94(LOW), 1.20(MOD) or 1.83gprotein kgbody mass−1 day−1 (HIGH)]. Urine collected over 24 h on day-4 and plasma collected after an overnight fast on day-5 were analyzed for free AA (plasma) and 3-methylhistidine (3MH; plasma and urine), a marker of myofibrillar protein breakdown. There was an effect of protein intake (HIGH > MOD/LOW; P < 0.05) on fasted plasma essential AA, branched chain AA and 3MH but no effect on 24-h urinary 3-MH excretion. Consuming a previously determined optimal daily protein intake of 1.83 g kg−1 day−1 during endurance training maintains fasted plasma free AA and may attenuate myofibrillar protein catabolism, although this latter effect was not detected in 24-h urinary excretion. The maintenance of the metabolically active free plasma AA pool may support greater recovery from exercise and contribute to the previously determined greater whole-body net protein balance in this athletic population. TRN: NCT02801344 (June 15, 2016).

Sportomics method to assess acute phase proteins in Olympic level athletes using dried blood spots and multiplex assay

Article

Full-text available

Nov 2022

Sportomics is a subject-centered holistic method similar to metabolomics focusing on sports as the metabolic challenge. Dried blood spot is emerging as a technique due to its simplicity and reproducibility. In addition, mass spectrometry and integrative computational biology enhance our ability to understand exercise-induced modifications. We studied inflammatory blood proteins (Alpha-1-acid glycoprotein—A1AG1; Albumin; Cystatin C; C-reactive protein—CRP; Hemoglobin—HBA; Haptoglobin—HPT; Insulin-like growth factor 1; Lipopolysaccharide binding protein—LBP; Mannose-binding lectin—MBL2; Myeloperoxidase—PERM and Serum amyloid A1—SAA1), in 687 samples from 97 World-class and Olympic athletes across 16 sports in nine states. Data were analyzed with Spearman's rank-order correlation. Major correlations with CRP, LBP; MBL2; A1AG1, and SAA1 were found. The pairs CRP-SAA1 and CRP-LBP appeared with a robust positive correlation. Other pairs, LBP-SAA1; A1AG1-CRP; A1AG1-SAA1; A1AG1-MBL, and A1AG1-LBP, showed a broader correlation across the sports. The protein–protein interaction map revealed 1500 interactions with 44 core proteins, 30 of them linked to immune system processing. We propose that the inflammation follow-up in exercise can provide knowledge for internal cargo management in training, competition, recovery, doping control, and a deeper understanding of health and disease.

Impact of Physical Activity on the Characteristics and Metabolic Consequences of Alcohol Consumption: A Cross-Sectional Population-Based Study

Article

Full-text available

Nov 2022
Int J Environ Res Publ Health

Sedentary lifestyle and excessive alcohol drinking are major modifiable risk factors of health. In order to shed further light on the relationships between physical activity and health consequences of alcohol intake, we measured biomarkers of liver function, inflammation, lipid status and fatty liver index tests in a large population-based sample of individuals with different levels of physical activity, alcohol drinking and other lifestyle risk factors. The study included 21,050 adult participants (9940 men, 11,110 women) (mean age 48.2 ± 13.3 years) of the National FINRISK Study. Data on physical activity, alcohol drinking, smoking and body weight were recorded. The participants were classified to subgroups according to gender, levels of physical activity (sedentary, low, moderate, vigorous, extreme), alcohol drinking levels (abstainers, moderate drinkers, heavy drinkers) and patterns (regular or binge, types of beverages preferred in consumption). Serum liver enzymes (GGT, ALT), C-reactive protein (CRP) and lipid profiles were measured using standard laboratory techniques. Physical activity was linearly and inversely related with the amount of alcohol consumption, with the lowest alcohol drinking levels being observed in those with vigorous or extreme activity (p < 0.0005). Physically active individuals were less frequently binge-type drinkers, cigarette smokers or heavy coffee drinkers than those with sedentary activity (p < 0.0005 for linear trend in all comparisons). In the General Linear Model to assess the main and interaction effects of physical activity and alcohol consumption on biomarker status, as adjusted for anthropometric measures, smoking and coffee consumption, increasing levels of physical activity were found to be associated with more favorable findings on serum GGT (p < 0.0005), ALT (p < 0.0005 for men), cholesterol (p = 0.025 for men; p < 0.0005 for women), HDL-cholesterol (p < 0.0005 for men, p = 0.001 for women), LDL-cholesterol (p < 0.03 for men), triglycerides (p < 0.0005 for men, p < 0.03 for women), CRP (p < 0.0005 for men, p = 0.006 for women) and fatty liver index (p < 0.0005). The data support the view that regular moderate to vigorous physical activity may counteract adverse metabolic consequences of alcohol consumption on liver function, inflammation and lipid status. The role of physical activity should be further emphasized in interventions aimed at reducing health problems related to unfavorable risk factors of lifestyle.

The combination of trailer transport and exercise increases gastrointestinal permeability and markers of systemic inflammation in horses

Article

Oct 2022
EQUINE VET J

Background: Leaky gut syndrome (LGS) is an idiopathic disorder characterised by alterations in intestinal permeability and low-grade systemic inflammation. Factors contributing to development of LGS are not well-understood but physiological stressors such as exercise and transport may play a role which may be of pathophysiological relevance in horses. Objectives: To characterise the combined effect of transport stress and exercise on gastrointestinal permeability, and to determine whether these effects are associated with increased inflammatory biomarkers in plasma. Study design: Controlled, randomised, cross-over study. Methods: Horses (n=8 per group) were given a gastrointestinal permeability tracer (iohexol; 5.6% solution; 1mL/kg bwt) via nasogastric entubation prior to being assigned to a stressed (EX; one hour of trailer transport immediately followed by 30 minutes moderate intensity exercise; n=4) or sedentary control (CON; n=4) group. Plasma samples were obtained prior to iohexol administration (P1), after transport (P2), at exercise cessation (P3), and at 1 (P4), 2 (P5), 4 (P6) and 8 (P7) hours after cessation of exercise and were analysed for iohexol, inflammatory biomarkers (SAA, LPS, IFABP, LBP) and tight junction proteins (zonulin). Fecal samples were collected at times corresponding to before and after stress from both groups and analysed for zonulin. Data were analysed using a 2-way RM ANOVA. Results: In EX horses, a significant increase in iohexol was observed at P2 (1.5±0.24μg/ml; p=0.03), P3 (2.1±0.29μg/ml; p<0.001), P4 (2.1±0.17μg/ml; p<0.001) compared with P1 (0.7±0.21μg/ml); iohexol was significantly higher in EX than CON horses at P3 (p<0.001), P4 (p<0.001) and P5 (p=0.003). LPS and SAA were significantly higher in EX than CON at P4 (p<0.001) and P6 (p=0.04), respectively. Main limitations: Data from our small sample size may not be generalisable to the larger equine population. Conclusions: Combined transport and exercise increases gastrointestinal permeability and systemic SAA and LPS. The model described herein may be useful in further studies on the role of alterations in gastrointestinal permeability in equine disease. This article is protected by copyright. All rights reserved.

Exertional heat stroke: pathophysiology and risk factors

Article

Full-text available

Oct 2022

Exertional heat stroke, the third leading cause of mortality in athletes during physical activity, is the most severe manifestation of exertional heat illnesses. Exertional heat stroke is characterised by central nervous system dysfunction in people with hyperthermia during physical activity and can be influenced by environmental factors such as heatwaves, which extend the incidence of exertional heat stroke beyond athletics only. Epidemiological data indicate mortality rates of about 27%, and survivors display long term negative health consequences ranging from neurological to cardiovascular dysfunction. The pathophysiology of exertional heat stroke involves thermoregulatory and cardiovascular overload, resulting in severe hyperthermia and subsequent multiorgan injury due to a systemic inflammatory response syndrome and coagulopathy. Research about risk factors for exertional heat stroke remains limited, but dehydration, sex differences, ageing, body composition, and previous illness are thought to increase risk. Immediate cooling remains the most effective treatment strategy. In this review, we provide an overview of the current literature emphasising the pathophysiology and risk factors of exertional heat stroke, highlighting gaps in knowledge with the objective to stimulate future research.

Gastrointestinale Erkrankungen

Chapter

Sep 2023

Plasma measurements of the dual sugar test reveal carbohydrate immediately alleviates intestinal permeability caused by exertional heat stress

Article

Full-text available

Sep 2023
J PHYSIOL-LONDON

The aim of this set of randomised cross‐over studies was to determine the impact of progressive heat exposure and carbohydrate or protein feeding during exertional stress on small intestine permeability using a dual sugar test. In our previous work, and typically in the field, recovery of lactulose and l ‐rhamnose is measured cumulatively in urine. This follow‐up study exploits our novel high‐performance anion exchange chromatography with pulsed amperometric detection (HPAEC‐PAD) protocol to accurately quantify the sugars in plasma. Endurance‐trained participants completed experimental trial A (ET‐A; n = 8), consisting of 2 h running at 60% in temperate, warm and hot ambient conditions, and/or experimental trial B (ET‐B; n = 9), consisting of 2 h running at 60% in the heat while consuming water, carbohydrate or protein. Blood samples were collected and plasma lactulose (L) and l ‐rhamnose (R) appearance, after dual sugar solution ingestion at 90 min of exercise, was quantified by HPAEC‐PAD to measure plasma L/R and reveal new information about intestinal permeability immediately post‐exercise and during recovery. In ET‐A, plasma L/R increased immediately post‐exercise in hot compared with temperate and warm conditions, while, in ET‐B, carbohydrate alleviated this, and this information was otherwise missed when measuring urine L/R. Consuming carbohydrate or protein before and during exercise attenuated small intestine permeability throughout recovery from exertional heat stress. We recommend using the dual sugar test with quantification of plasma sugars by HPAEC‐PAD at intervals to maximise intestinal permeability data collection in exercise gastroenterology research, as this gives additional information compared to urinary measurements. image Key points Intestinal permeability is typically assessed using a dual sugar test, by administering a drink containing non‐metabolisable sugars (e.g. lactulose (L) and l ‐rhamnose (R)) that can enter the circulation by paracellular translocation when the epithelium is compromised, and are subsequently measured in urine. We demonstrate that our recently developed ion chromatography protocol can be used to accurately quantify the L/R ratio in plasma, and that measuring L/R in plasma collected at intervals during the post‐exercise recovery period reveals novel acute response information compared to measuring 5‐h cumulative urine L/R. We confirm that exercising in hot ambient conditions increases intestinal epithelial permeability immediately after exercise, while consuming carbohydrate or protein immediately before and during exercise attenuates this. We recommend using our dual sugar absorption test protocol to maximise intestinal epithelial permeability data collection in exercise gastroenterology research and beyond.

Gastrointestinal disorders and leaky gut syndrome in endurance athletes

Article

Full-text available

Sep 2023

Gastrointestinal disorders are common in endurance-sport athletes, and can negatively affect physical performance and general health. During long lasting exercises such like ultramarathon, triathlon, marathon a characteristic phenomenon is the increase in the concentration many proinflammatory markers and proteins such like IL-1, IL-6, TNF-alfa, LPS, CK and C-reactive protein. Despite observed biochemical changes on of the typical “side effects” of physical activity is increased intestinal permeability, also called to as leaky gut. Recent research has demonstrated that even one hour of of intense endurance training note even with a maximum work capacity can lead to leaky gut symptoms and gastrointestinal disorders. Increased intestinal permeability is accomplished with changes of numerus molecular biomarkers, that indicate presence of this disease state and the degradation of the intestinal mucosa, such like lipopolysaccharides, zonulin, lactulose/rhamnose ratio, occludin and I-FABP, and many other. The understanding of this processes and understanding of the molecular mechanisms involved in the induction of leaky gut syndrome can lead to funding new methods and means of both avoiding and treating this condition.

Możliwość zastosowania diety FODMAP w leczeniu zaburzeń żołądkowo-jelitowych u sportowców

Article

Full-text available

Aug 2023

FODMAP jest to grupa szybko fermentujących i słabo przyswajalnych oligo-, di- i monosacharydów oraz poliolii, występująca powszechnie w wielu produktach spożywczych, których spożycie nasila objawy kliniczne ze strony przewodu pokarmowego. Ból brzucha, biegunka, wzdęcia to najczęściej wymieniane problemy pojawiające się u osób z zespołem jelita nadwrażliwego (IBS) ale również u sportowców dyscyplin wytrzymałościowych. Objawy te mogą powodować złe samopoczucie, obniżać jakość oraz efektywność treningu, co w konsekwencji może wpływać na osiągane wyniki sportowe. Zastosowanie diety z ograniczeniem produktów o wysokiej zawartości FODMAP zmniejsza lub eliminuje problemy żołądkowo-jelitowe u osób z zespołem jelita nadwrażliwego. Taka interwencja żywieniowa może również przynieść potencjalne korzyści w leczeniu zaburzeń żołądkowo-jelitowych indukowanych wysiłkiem fizycznym. W pracy przedstawiono poszczególne składniki FODMAP, mechanizm powstawania czynnościowych zaburzeń przewodu pokarmowego oraz zasady diety Low FODMAP. W niniejszym przeglądzie oceniono skuteczność diety z ograniczeniem łatwo fermentujących węglowodanów oraz jej ewentualnych niepożądanych następstw w leczeniu osób z IBS oraz w redukowaniu dolegliwości żołądkowo-jelitowych u sportowców.

Design of Antioxidant Nanoparticle, which Selectively Locates and Scavenges Reactive Oxygen Species in the Gastrointestinal Tract, Increasing The Running Time of Mice

Article

Full-text available

Aug 2023

Excess reactive oxygen species (ROS) produced during strong or unfamiliar exercise cause exercise‐induced gastrointestinal syndrome (EIGS), leading to poor health and decreased exercise performance. The application of conventional antioxidants can neither ameliorate EIGS nor improve exercise performance because of their rapid elimination and severe side effects on the mitochondria. Hence, a self‐assembling nanoparticle‐type antioxidant (RNPO) that is selectively located in the gastrointestinal (GI) tract for an extended time after oral administration is developed. Interestingly, orally administered RNPO significantly enhances the running time until exhaustion in mice with increasing dosage, whereas conventional antioxidants (TEMPOL) tends to reduce the running time with increasing dosage. The running (control) and TEMPOL groups show severe damage in the GI tract and increased plasma lipopolysaccharide (LPS) levels after 80 min of running, resulting in fewer red blood cells (RBCs) and severe damage to the skeletal muscles and liver. However, the RNPO group is protected against GI tract damage and elevation of plasma LPS levels, similar to the nonrunning (sedentary) group, which prevents damage to the whole body, unlike in the control and TEMPOL groups. Based on these results, it is concluded that continuous scavenging of excessive intestinal ROS protects against gut damage and further improves exercise performance.

The Impact of a 24-h Low and High Fermentable Oligo- Di- Mono-Saccharides and Polyol (FODMAP) Diet on Plasma Bacterial Profile in Response to Exertional-Heat Stress

Article

Full-text available

Jul 2023

Exertional-heat stress (EHS) compromises intestinal epithelial integrity, potentially leading to the translocation of pathogenic agents into circulation. This study aimed to explore the impact of EHS on the systemic circulatory bacterial profile and to determine the impact of a short-term low (LFOD) and high (HFOD) fermentable oligo- di- mono-saccharide and polyol dietary intervention before EHS on this profile. Using a double-blind randomized cross-over design, thirteen endurance runners (n = 8 males, n = 5 females), with a history of exercise-associated gastrointestinal symptoms (Ex-GIS), consumed a 24 h LFOD and HFOD before 2 h running at 60% V.O2max in 35.6 °C. Blood and fecal samples were collected pre-EHS to determine plasma microbial DNA concentration, and sample bacteria and short chain fatty acid (SCFA) profiles by fluorometer quantification, 16S rRNA amplicon gene sequencing, and gas chromatography, respectively. Blood samples were also collected post-EHS to determine changes in plasma bacteria. EHS increased plasma microbial DNA similarly in both FODMAP trials (0.019 ng·μL−1 to 0.082 ng·μL−1) (p < 0.01). Similar pre- to post-EHS increases in plasma Proteobacteria (+1.6%) and Firmicutes (+0.6%) phyla relative abundance were observed in both FODMAP trials. This included increases in several Proteobacteria genus (Delftia and Serratia) groups. LFOD presented higher fecal Firmicutes (74%) and lower Bacteroidota (10%) relative abundance pre-EHS, as a result of an increase in Ruminococcaceae and Lachnospiraceae family and respective genus groups, compared with HFOD (64% and 25%, respectively). Pre-EHS plasma total SCFA (p = 0.040) and acetate (p = 0.036) concentrations were higher for HFOD (188 and 178 μmol·L−1, respectively) vs. LFOD (163 and 153 μmol·L−1, respectively). Pre-EHS total fecal SCFA concentration (119 and 74 μmol·g−1; p < 0.001), including acetate (74 and 45 μmol·g−1; p = 0.001), butyrate (22 and 13 μmol·g−1; p = 0.002), and propionate (20 and 13 μmol·g−1; p = 0.011), were higher on HFOD vs LFOD, respectively. EHS causes the translocation of whole bacteria into systemic circulation and alterations to the plasma bacterial profile, but the FODMAP content of a 24 h diet beforehand does not alter this outcome.

How intense exercise performed in two different training phases affects elite rowers' intestinal permeability

Preprint

Full-text available

Jun 2023

Background: The study aimed to check the effect of the 2000m ergometer test on the gut permeability in elite rowers in two different phases of sport training. As an inflammatory marker during the competitive phase is higher, we hypothesize that markers of intestinal permeability will also be more elevated in that phase. Methods: The study was performed during an annual preparation and competitive phase of training. Ten elite rowers of the Polish Rowing Team after applying the inclusion/exclusion criteria participated in the study. In both periods, the participants performed a 2000m ergometer test. Each time the blood samples were taken in the schedule: pre-, post-, and 1-hour post-exercise. Il-6, I-FABP, LPS, LBP, and zonulin levels were measured. Results: There were significantly lower values of I-FABP and IL-6 observed in Post-exercise time in Test II compared to Test I. The resting value of LPS was significantly lower in Test II compared to Test I. Also, resting levels of LBP and zonulin were lower in Test II, but the differences were not significant. Conclusions: Changes in gut permeability markers after extreme exercise tests may be the results of adaptive mechanisms occurring, indicating that rationally conducted training significantly decreases intestinal permeability. The ability of the gut to adapt to high levels of performance is crucial for the elite athlete.

Lifestyle im Management chronisch-entzündlicher Darmerkrankungen – Teil 2: SportLifestyle in the management of inflammatory bowel disease—part 2: physical activity

Article

Jun 2023

Background The prevalence of inflammatory bowel disease (IBD) is increasing worldwide. Besides nutritional factors, reduced physical activity is also recognized as a significant influencing factor, leading to a reduction in muscle mass and an increase in fat reserves and a deterioration of the cardiovascular system. These factors can increase the risk of developing IBD and/or have an adverse impact on disease progression.AimThe goal of this paper is to explain the approach and aspects to be considered when using exercise and physical activity in the treatment of IBD.Materials and methodsIn addition to the intestinal and extraintestinal findings and the inflammatory activity, the physical constitution of patients with IBD is of tremendous importance for treatment that includes exercise and physical activity. Although the positive influence of exercise and physical activity on patients with IBD is a proven fact, there are no specific guidelines regarding the extent and type exercise and physical activity. Therefore, recommendations based on study results are given as guidelines for exercise interventions in patients with IBD.Results and conclusionExercise and physical activity adapted to the disease state can positively influence the patient’s quality of life and the course of the disease. The combination of endurance and strength training can improve body composition and physical performance. In view of the heterogeneity of patients, however, physical exercise interventions must also be individualized.

Functional Foods, Supplements, and Dietary Approaches in Sports and Clinical Nutrition

Book

Full-text available

Jun 2023

Nutritional research includes the investigation of various dietary approaches, functional foods, and supplements, to guide personalized advice to enhance health and/or performance (1–8). Evidence-based decisions must be made based on the most recent advances in research. Therefore, we created a special issue entitled “Functional Foods, Supplements, and Dietary Approaches in Sports and Clinical Nutrition”, which consisted of a number of leading experts. In the special issue, 7 papers were focused on health or clinical populations and 4 manuscripts had a sport or performance focus. In this editorial, we briefly highlight the key aspects of each manuscript.

Amino Acid-Based Beverage Interventions Ameliorate Exercise-Induced Gastrointestinal Syndrome in Response to Exertional-Heat Stress: The Heat Exertion Amino Acid Technology (HEAAT) Study

Article

Full-text available

May 2023

The study aimed to determine the effects of two differing amino acid beverage interventions on biomarkers of intestinal epithelial integrity and systemic inflammation in response to an exertional-heat stress challenge. One week after the initial assessment, participants ( n = 20) were randomly allocated to complete two exertional-heat stress trials, with at least 1 week washout. Trials included a water control trial (CON), and one of two possible amino acid beverage intervention trials (VS001 or VS006). On VS001 (4.5 g/L) and VS006 (6.4 g/L), participants were asked to consume two 237-ml prefabricated doses daily for 7 days before the exertional-heat stress, and one 237-ml dose immediately before, and every 20 min during 2-hr running at 60% maximal oxygen uptake in 35 °C ambient conditions. A water volume equivalent was provided on CON. Whole blood samples were collected pre-, immediately post-, 1 and 2 hr postexercise, and analyzed for plasma concentrations of cortisol, intestinal fatty acid protein, soluble CD14, and immunoglobulin M (IgM) by ELISA, and systemic inflammatory cytokines by multiplex. Preexercise resting biomarker concentrations for all variables did not significantly differ between trials ( p > .05). A lower response magnitude for intestinal fatty acid protein (mean [95% CI]: 249 [60, 437] pg/ml, 900 [464, 1,336] pg/ml), soluble CD14 (−93 [−458, 272] ng/ml, 12 [−174, 197] ng/ml), and IgM (−6.5 [−23.0, 9.9] MMU/ml, −10.4 [−16.2, 4.7] MMU/ml) were observed on VS001 and V006 compared with CON ( p < .05), respectively. Systemic inflammatory response profile was lower on VS001, but not VS006, versus CON ( p < .05). Total gastrointestinal symptoms did not significantly differ between trials. Amino acid beverages’ consumption (i.e., 4.5–6.4 g/L), twice daily for 7 days, immediately before, and during exertional-heat stress ameliorated intestinal epithelial integrity and systemic inflammatory perturbations associated with exercising in the heat, but without exacerbating gastrointestinal symptoms.

Walking 200 min per day keeps the bariatric surgeon away

Article

May 2023

Exercise and increased physical activity are vital components of the standard treatment guidelines for many chronic diseases such as diabetes, obesity and cardiovascular disease. Although strenuous exercise cannot be recommended to people with numerous chronic conditions, walking is something most people can perform. In comparison to high-intensity training, the metabolic consequences of low-intensity walking have been less well studied. We present here a feasibility study of a subject who performed an exercise intervention of low-intensity, non-fatiguing walking on a deskmill/treadmill for 200 min daily, approximately the average time a German spends watching television per day. This low-impact physical activity has the advantages that it can be done while performing other tasks such as reading or watching TV, and it can be recommended to obese patients or patients with heart disease. We find that this intervention led to substantial weight loss, comparable to that of bariatric surgery. To study the metabolic changes caused by this intervention, we performed an in-depth metabolomic profiling of the blood both directly after walking to assess the acute changes, as well as 1.5 days after physical activity to identify the long-term effects that persist. We find changes in acylcarnitine levels suggesting that walking activates fatty acid beta oxidation, and that this mitochondrial reprogramming is still visible 1.5 days post-walking. We also find that walking mildly increases gut permeability, leading to increased exposure of the blood to metabolites from the gut microbiome. Overall, these data provide a starting point for designing future intervention studies with larger cohorts.

Assessment of gastrointestinal health in racing Alaskan sled dogs using capsule endoscopy and inflammatory cytokines

Article

May 2023

Objectives: Exercise-induced gastrointestinal syndrome occurs in dogs and people and might compromise athlete performance by increasing intestinal permeability and causing gastrointestinal erosions. Racing sled dogs often receive acid suppressant prophylaxis which decreases the incidence of gastric erosions induced by exercise. The objectives were to quantify intestinal injury by measuring serum pro-inflammatory cytokine concentrations before and after exercise and to evaluate gastrointestinal mucosa using video capsule endoscopy after exercise. Materials and methods: Prospective study of 12 racing Alaskan sled dogs receiving approximately 1 mg/kg omeprazole once daily from the day before the race until race completion. Blood was drawn before and 8 to 10 hours after an endurance race for the quantification of cytokines. Gastrointestinal tract mucosa was assessed with video capsule endoscopy immediately post-race. Results: Eight of nine dogs (89%; 95% confidence interval 52 to 100%) had gastric erosions; all dogs (100%, 95% confidence interval 63 to 100%) had small intestinal erosions. Most of the dogs (seven of nine) had straw or foreign material present. Cytokine levels were not different from before to after the race. Clinical significance: Video capsule endoscopy identified gastrointestinal tract mucosal erosions after exercise in all dogs receiving once-daily omeprazole treatment, though other causes for the lesions besides exercise are possible.

Low Ferritin and Anemic Conditions in Endurance Athletes

Chapter

May 2023

Iron deficiency (ID) and iron deficiency anemia (IDA) are global health problems. Iron is the number one nutritional deficiency in the world and the top-ranking cause of anemia. ID refers to low iron stores and inadequate availability, whereas anemia refers to low hemoglobin. Endurance athletes are at a high risk for anemia and nutritional deficiencies related to the intensity and duration of training. Progressive decreases in iron stores can result in symptoms of fatigue, weakness, and performance decline with or without true anemia. Although iron deficiency is not related to all anemias, IDA is the most prevalent form seen in the athletic population. The most common causes of iron deficiency, with or without anemia, are often multifactorial including poor dietary iron intake and decreased absorption, as well as various types of blood loss. A good history and physical examination are necessary to rule out more serious medical illnesses as well as screen for low iron. Healthcare providers must be astute clinicians to interpret the laboratory studies for various types of anemia and different stages of iron deficiency, particularly in the context of athletic participation. Intense exercise, endurance training, and illness have significant, yet predictable, effects on test results. General treatment of anemia and nutritional deficiencies in endurance athletes is individualized to both the athlete and the underlying cause(s). IDA and ID treatment is specifically focused on dietary changes and, when indicated, oral or parenteral supplementation.KeywordsAnemiaHemoglobinHemolysisFerritinHepcidinIron deficiencyExerciseEndurancePseudoanemia

The effects of low and normal dose ice slurry ingestion on endurance capacity and intestinal epithelial injury in the heat

Article

Apr 2023
J SCI MED SPORT

Objectives: Compare the effects of ice slurry ingestion at low and normal doses on endurance capacity and exertional heat stress-induced gastrointestinal perturbations. Design: Randomised, cross-over design. Methods: Twelve physically active males completed four treadmill running trials, ingesting ice slurry (ICE) or ambient drink (AMB) at 2 g·kg-1 (Normal; N) or 1 g·kg-1 (Low; L) doses every 15-min during exercise and 8 g·kg-1 (N) or 4 g·kg-1 (L) pre- and post-exercise. Pre-, during and post-exercise serum intestinal fatty-acid binding protein ([I-FABP]) and lipopolysaccharide ([LPS]) concentrations were determined. Results: Pre-exercise gastrointestinal temperature (Tgi) was lower in L + ICE than L + AMB (p < 0.05), N + ICE than N + AMB (p < 0.001) and N + ICE than L + ICE (p < 0.001). Higher rate of Tgi rise (p < 0.05) and lower estimated sweat rate (p < 0.001) were observed in N + ICE than N + AMB. Rate of Tgi rise was similar at low dose (p = 0.113) despite a lower estimated sweat rate in L + ICE than L+AMB (p < 0.01). Time-to-exhaustion was longer in L + ICE than L + AMB (p < 0.05), but similar between N + ICE and N + AMB (p = 0.142) and L + ICE and N + ICE (p = 0.766). [I-FABP] and [LPS] were similar (p > 0.05). Conclusions: L + ICE elicited a lower heat dissipation compensatory effect with similar endurance capacity as N + ICE. Ice slurry conferred no protection against exertional heat stress-induced gastrointestinal perturbations.

Apple puree as a natural fructose source provides an effective alternative carbohydrate source for fuelling half-marathon running performance

Article

Apr 2023

Carbohydrate supplementation during endurance exercise is known to improve performance, but the effects of food-based approaches in running exercise are understudied. Therefore, this study investigated the performance and gastrointestinal (GI) effects of a carbohydrate supplement containing a natural fructose source compared with a highly processed fructose source in a combined glucose-fructose supplement, during a half-marathon. Eleven trained runners (9 males, 2 females; age 32 ± 8 y, 89:53 ± 13:28 min half-marathon personal record) completed a familiarisation (8 miles) and two experimental trials (13.1 miles) on an outdoor running course, with blood and urine samples collected before and after the run. Subjective GI measures made throughout the run. Carbohydrate was provided as a natural fructose source in the form of apple puree (AP) or highly processed crystalline fructose (GF) in a 2:1 glucose-to-fructose ratio (additional required glucose was provided through maltodextrin). Half-marathon performance was not different between carbohydrate sources (AP 89:52 ± 09:33 min, GF 88:44 ± 10:09 min; P = 0.684). There were no interaction effects for GI comfort (P = 0.305) or other GI symptoms (P ≥ 0.211). There were no differences between carbohydrate sources in ad libitum fluid intake (AP 409 ± 206 mL; GF 294 ± 149 mL; P = 0.094) or any other urinary (P ≥ 0.724), blood-based (P ≥ 0.215) or subjective (P ≥ 0.421) measure. Apple puree as a natural fructose source was equivalent to crystalline fructose in supporting half-marathon running performance without increasing gastrointestinal symptoms.

An Overview of Exertional Heat Illness in Thoroughbred Racehorses: Pathophysiology, Diagnosis, and Treatment Rationale

Article

Full-text available

Feb 2023

Simple Summary Exertional Heat Illness (EHI) and its associated fatal form of heat injury, heat stroke (HS), is not a new disease. It has been described as the oldest known medical condition and its occurrence in humans dates back more than 2000 years. The condition occurs when an individual is unable to adequately dissipate the metabolic heat produced by physical exertion, and the resulting elevation of core body temperature can cause damage to multiple organs. EHI in human subjects is a particular threat to the health and safety of athletes, both elite and recreational, military personnel, firefighters, and outdoor labourers. Similarly, EHI/HS in horses is not new, but progress in managing the condition has languished due to the relative lack of information provided in the veterinary literature. There is, however, an important similarity between racehorses and human athletes, in that both dissipate heat chiefly by evaporative sweating. Therefore, much that has been published on EHI in the human scientific literature can also serve to enlighten us about the condition in horses. To ensure the welfare of racehorses, the authors have described EHI in detail. It is imperative that veterinarians working at the racetrack can recognize the earliest clinical signs, understand its mechanism of action and the rationale for practical treatment options Abstract Exertional heat illness (EHI) is a complex medical disease. The thoroughbred (TB) racehorse is at considerable risk because of the intensity of its exercise activity and its high rate of metabolic heat production. The pathophysiology of EHI can combine aspects of both the heat toxicity pathway and the heat sepsis or endotoxemic pathway. Treatment regimes depend upon the detection of earliest clinical signs, rapid assessment, aggressive cooling and judicious use of ancillary medications. Ice-cold water provides the most rapid cooling, consistent with the need to lower core body temperature before tissue damage occurs. Research into EHI/HS by inducing the condition experimentally is ethically unjustifiable. Consequently, leading researchers in the human field have conceded that “most of our knowledge has been gained from anecdotal incidents, gathered from military personnel and athletes who have collapsed during or following physical activity, and that retrospective and case studies have provided important evidence regarding recognition and treatment of EHI”. The authors’ review into EHI shares that perspective, and the recommendations made herein are based on observations of heat-affected racehorses at the racetrack and their response, or lack of response, to treatment. From 2014 to 2018, 73 race meetings were attended, and of the 4809 individual starters, signs of EHI were recorded in 457. That observational study formed the basis for a series of articles which have been published under the title, ‘EHI in Thoroughbred racehorses in eastern Australia’, and forms the background for this review.

СПОСІБ ПОГЛИБЛЕНОЇ ОЦІНКИ ГАСТРО- ТА ЕНТЕРОТОКСИЧНОГО ВПЛИВУ ЯК ПОБІЧНОЇ ДІЇ ЛІКІВ РІЗНИХ ФАРМАКОЛОГІЧНИХ ГРУП

Article

Full-text available

Nov 2022

РЕЗЮМЕ. На фоні розширення фармацевтичного ринку світу зростання призначень препаратів, надзвичайно широкого неконтрольованого їх застосування в процесі самолікування – особливої уваги заслуговують питання щодо негативного впливу ліків різних фармакологічних груп на органи травної системи. Враховуючи, що надзвичайно розповсюдженими побічними ефектами ліків є саме ураження органів травної системи, зокрема шлунково-кишкового тракту, актуальність питання щодо оцінки їх стану за дії лікарських засобів є безумовною. Моніторинг побічної дії ліків різних фармакотерапевтичних груп щодо впливу на шлунково-кишковий тракт, детальне дослідження стану слизових шлунка та кишечника, зокрема, за тривалого застосування препаратів на тлі хронічних захворювань ревматичного характеру, онкопатології, коморбідних станів, а також за наявності супутніх захворювань травної системи, є пріоритетними завданнями як фармакологів-експериментаторів, так і клініцистів. Необхідність детальної оцінки уражень слизових оболонок шлунка та кишечника потребує розробки нових препаратів, вивчення їх механізмів дії та особливостей фармакодинаміки, фармакокінетики, тропності до певних органів тощо, вивчення взаємодії препаратів різних фармакологічних та/або фармакотерапевтичних груп на тлі різноманітних захворювань, в т. ч. коморбідних станів, навіть, тих, що прямо не пов’язані з патологією шлунка і кишечника. Необхідність дослідження побічної, зокрема, гастро- та ентеротоксичної дії ліків, незаперечна, що потребує застосування відповідних методів оцінки стану слизових оболонок шлунка та кишечника. Мета роботи – запропонувати спосіб поглибленої оцінки стану слизових оболонок шлунка та кишечника за дослідження гастротоксичної та ентеротоксичної дії ліків, що не призначені для лікування власне патології шлунка та кишечника, і застосовуються за різних патологічних станів, в тому числі – за коморбідних. Матеріал та методи. У дослідженні використані статевозрілі нелінійні білі щури обох статей. Макроскопічно проведене обстеження слизових оболонок шлунка та кишечника. Визначені наявність, число та розмір усіх деструкцій, розроблені методи оцінки частоти та інтенсивності їхнього ураження як на моделях різних патологічних станів (в т. ч. – коморбідного), так і за застосування деяких НПЗП. Запропонована формула для визначення гастро- та ентеротоксичної активності лікарських засобів. Результати. Запропонований детальний спосіб розширеної оцінки стану слизових оболонок шлунка та кишечника з урахуванням таких симптомів ураження як набряк (в т. ч. крипт), гіперемія (локальна та тотальна), петехії, крововиливи, ерозії, виразки. Рекомендовано визначати такі показники, як частота гастро- та/або ентеропатії, інтенсивність кожного з видів ураження та загальну інтенсивність гастропатії або інтенсивність ентеропатії, які найбільшою мірою характеризують усі зміни слизових оболонок шлунка та кишечника, ступінь цих змін за бальною шкалою. Зазначені показники можуть надати узагальнюючу характеристику стану слизових оболонок цих органів, як за умов патологічного процесу, так і за умов токсичного впливу ліків. Частоту ушкоджень слизових оболонок шлунка та кишечника як за дії ліків, так і за патологічних станів, пропонується визначати шляхом підрахунку кожного з видів ушкодження відносно загальної кількості тварин у групі. Інтенсивність кожного з видів ушкодження слизових оболонок шлунка чи кишечника пропонується проводити за бальною оцінкою, яка, по-суті, відображає ступінь ушкодження. Кількість балів за кожним із зазначених ушкоджень слід підраховувати в усіх тварин даної групи. За відношенням загальної кількості балів за певним видом ушкоджень до загальної кількості тварин у групі потрібно визначати інтенсивність кожного з уражень (інтенсивність гіперемії, інтенсивність набряку тощо), тобто розраховувати інтенсивність як відношення сумарної кількості балів для всіх тварин, у яких спостерігалося певне ушкодження, до кількості тварин в групі. Наведено формулу для визначення гастро- та ентеротоксичної активності препаратів. Надані конкретні приклади підрахунку частоти та інтенсивності ушкодження слизових оболонок шлунка і кишечника, а також приклад визначення гастротоксичності нестероїдних протизапальних препаратів. Висновки. Запропоновано поглиблений спосіб оцінки стану слизових оболонок шлунка та кишечника за вивчення побічної (гастро- та ентеротоксичної) дії ліків різних фармакологічних груп. Наведені конкретні приклади визначення частоти та інтенсивності ушкоджень слизової оболонки шлунка на тлі патологічних станів різного ґенезу, а також приклади дослідження гастротоксичного впливу нестероїдних протизапальних препаратів, різних за селективністю до циклооксигенази.

Risedronate prevents exercise-induced hypercalcemia but not nausea or vomit in humans: a double-blind randomized controlled trial

Preprint

Full-text available

Nov 2022

Background: Reportedly, nausea or vomiting after heavy exercise was associated with post-exercise increased blood calcium (Ca) levels, which was correlated with enhanced bone resorption. Methods: We conducted a randomized, double-blind, placebo-controlled trial, enrolling 104 healthy trained male members of the Japan Self-Defense Forces. Risedronate (17.5 mg) or placebo was prescribed 3 and 10 days before heavy exercise lasting approximately 5 hours. We estimated Ca levels immediately after the exercise using the correlation between blood Ca and time from the end of exercise. The primary outcome was the severity of nausea or vomiting assessed by a visual analog scale during or post-exercise. The secondary outcomes included clinical symptoms associated with heat illness, post-exercise serum total Ca (tCa), whole blood ionized Ca (iCa), and serum tartrate-resistant acid phosphatase 5b (TRACP-5b) levels. Results: The mean age and baseline estimated glomerular filtration rate (eGFR) were 26 years and 87 mL/min/1.73 m², respectively. The exercise resulted in a 4.5% weight loss. The two groups were comparable in terms of the symptoms, including primary outcome, and post-exercise eGFR. However, post-exercise estimated tCa and TRACP-5b were significantly lower with risedronate. A similar result was observed for estimated iCa. The incidence of hypercalcemia (defined as an estimated tCa or iCa levels ≥ each median value of all subjects) and urinary Ca excretion were significantly lower with risedronate. A stronger treatment effect of risedronate on blood Ca levels was observed in participants who lost substantial bodyweight. Conclusion: Our strategy may help decrease the incidence of urinary stones often observed in marathon runners. Trial Registration Registered on www.umin.ac.jp (UMIN000032110)

Impact of exercise duration on gastrointestinal function and symptoms

Article

Dec 2022

The study aimed to determine the impact of exercise duration on gastrointestinal functional responses and gastrointestinal symptoms (GIS) in response to differing exercise durations. Endurance runners (n=16) completed three trials on separate occasions, randomised to 1 h (1-H), 2 h (2-H) and 3 h (3-H) of running at 60% V̇O 2max in temperate ambient temperature. Orocecal transit time (OCTT) was determined by lactulose challenge, with concomitant breath hydrogen (H 2 ) determination. Gastric slow wave activity was recorded using cutaneous electrogastrography (cEGG) pre and post exertion. GIS was determined using a modified visual analogue scale (mVAS). OCTT response was classified as very slow on all trials (~93-101 min) with no trial difference observed (P= 0.895). Bradygastria increased post-exercise on all trials (mean ± SD: 1-H: 10.9 ± 11.7%, 2-H: 6.2 ± 9.8% and 3-H: 13.2 ± 21.4%; P< 0.05). A reduction in the normal gastric slow wave activity (2-4 cycles/min) was observed post-exercise on 1-H only (-10.8 ± 17.6%; P= 0.039). GIS incidence and gut discomfort was higher on 2-H (81% and 12 counts) and 3-H (81% and 18 counts), compared to 1-H (69% and 6 counts) (P= 0.038 and P= 0.006, respectively). Severity of gut discomfort, total-GIS, upper-GIS, and lower-GIS increased during exercise on all trials (P< 0.05). Steady state exercise in temperate ambient conditions for 1 h, 2 h, and 3 h instigates perturbations in gastric slow wave activity compared to rest and hampers OCTT, potentially explaining the incidence and severity on exercise-associated GIS.

Pathophysiology of exertional heat illness in the Thoroughbred racehorse: Broadening perspective to include an exercise‐induced gastrointestinal syndrome in which endotoxaemia and systemic inflammation may contribute to the condition

Article

Dec 2022
EQUINE VET EDUC

The traditional approach to exertional heat illness (EHI) is based on the premise that external heat is the trigger and sole driver of the condition. During the last few decades, many researchers have suggested that climatic heat alone does not fully explain the pathophysiology of EHI, and a second pathway has been proposed which focuses on the gastrointestinal tract (GIT). The causal agent of EHI in Thoroughbred racehorses is the strenuous exercise of racing. The generation of metabolic heat is prodigious and can cause direct injury to the GIT. The associated redistribution of cardiac output to working muscles is most likely to subject the GIT to substantial hypo‐perfusion and if horses race under hot/humid conditions impairing thermoregulation this may exacerbate intestinal hyperthermia. Evidence in human athletes shows that the combination of intestinal hyperthermia and reduced blood flow causes a breakdown in the integrity of the mucosal barrier and leads to increased intestinal permeability, allowing leakage of endotoxin into the central circulation. Normally, protective immune mechanisms clear elevated endotoxin levels, but if there is immune dysfunction and the concentration of endotoxin exceeds a certain threshold, a systemic inflammatory response triggers a cytokine cascade with serious downstream consequences. It is argued that the cytokine inflammatory cascade, rather than core body hyperthermia contributes to the clinical progression of EHI when endotoxaemia is dominant. The authors have presented the current state of knowledge for human subjects and cited studies in racehorses which suggest its relevance. Acknowledgement of the gastrointestinal inflammatory pathway for EHI is important because it provides track veterinarians with a different perspective on prevention and treatment.

Female athlete triad affects rat intestinal morphology and sucrase-isomaltase expression

Article

Nov 2022
BRIT J NUTR

Female athletes follow a strict diet and perform rigorous exercise to boost their performance, which induces health issues called the female athlete triad (FAT), defined as the combination of disordered eating, amenorrhea, and low bone mineral density. It is known to have a significant effect on bones. However, its effects on the small intestine, which is responsible for nutrient uptake into the body, remain unclear. In this study, we created an animal model of FAT to examine its effects on digestive and absorptive molecules in the small intestine. Thirty 5-week-old female Sprague-Dawley (SD) rats with an initial body weight of about 147 g were divided into control (Con, n=7), exercise (Ex, n=7), food restriction (FR, n=8), and exercise plus food restriction (FAT, n=8) groups. The rats were subjected to four weeks of wheel running (Ex, FAT) and 50-40% food restriction (FR, FAT) to examine the effects on bone and typical digestive enzymes and transporters in the jejunum. Two-way ANOVA and the Kruskal-Wallis test were used for statistical analysis of normal and non-normal data, respectively. Four weeks of exercise and food restriction decreased bone weight (vs. other group p<0.01) and bone breaking power (vs. other group p<0.01). Villus height decreased in the jejunum (vs. other group p<0.01), but the expression of typical macronutrients digestive enzyme and absorptive molecules remained unchanged. In contrast, sucrase-isomaltase gene (vs. Ex p=0.02) and protein expression were increased (vs. other group p<0.05). The study findings show that FAT affects sucrase-isomaltase without histone methylation changes.

Does exertional heat stress impact gastrointestinal function and symptoms?

Article

Oct 2022
J SCI MED SPORT

Objectives Exertional-heat stress generates a thermoregulatory strain that exacerbates splanchnic hypoperfusion and sympathetic drive, but the effects on gastrointestinal function are poorly defined. The study aimed to determine the effects of exertional-heat stress on gastric myoelectrical activity, orocecal transit time (OCTT), and gastrointestinal symptoms (GIS). Design Randomised cross-over study. Methods Endurance runners (n = 16) completed 2 h of running at 60 % V̇O2max in 35 °C (HOT) and 22 °C (TEMP) ambient conditions. Surface electrogastrography (cEGG) was recorded pre- and post-exercise to determine gastric myoelectrical activity, a lactulose challenge was used to determine OCTT, and GIS were recorded using a modified visual analogue scale tool. Results Post-exercise Tre [HOT:38.8(38.5 to 39.0)°C and TEMP:38.1(37.8 to 38.4)°C] and Δ Tre [HOT:2.2(2.0 to 2.4)°C and TEMP:1.5(1.2 to 1.8)°C] was higher on HOT compared to TEMP (p < 0.001). Normal gastric myoelectrical cycle frequency reduced (p = 0.010) on HOT [−11.7(−20.8 to −2.6)%], but this decrease did not differ (p = 0.058) from TEMP [−2.7(−8.3 to 3.0)%]. Bradygastria increased post-exercise on both trials (HOT:11.3(2.3 to 20.4)%, p = 0.030; and TEMP:7.4(2.1 to 12.6)%, p = 0.009). OCTT did not differ between trials (p = 0.864) with transit response classified as very slow on both HOT (99(68 to 131)min) and TEMP (98(74 to 121)min). GIS incidence was higher on HOT (88 %) compared to TEMP (81 %), in accordance with greater total-GIS and upper-GIS severity (p = 0.005 and p = 0.033, respectively). Conclusions Running for 2 h at 60 % V̇O2max in either hot or temperate ambient conditions instigates perturbations in myoelectrical activity and OCTT, with GIS incidence and severity greater in hot conditions.

Differences in gut microbiota profile between women with active lifestyle and sedentary women

Article

Full-text available

Feb 2017
PLOS ONE

Physical exercise is a tool to prevent and treat some of the chronic diseases affecting the world’s population. A mechanism through which exercise could exert beneficial effects in the body is by provoking alterations to the gut microbiota, an environmental factor that in recent years has been associated with numerous chronic diseases. Here we show that physical exercise performed by women to at least the degree recommended by the World Health Organization can modify the composition of gut microbiota. Using high-throughput sequencing of the 16s rRNA gene, eleven genera were found to be significantly different between active and sedentary women. Quantitative PCR analysis revealed higher abundance of health-promoting bacterial species in active women, including Faecalibacterium prausnitzii, Roseburia hominis and Akkermansia muciniphila. Moreover, body fat percentage, muscular mass and physical activity significantly correlated with several bacterial populations. In summary, we provide the first demonstration of interdependence between some bacterial genera and sedentary behavior parameters, and show that not only does the dose and type of exercise influence the composition of gut microbiota, but also the breaking of sedentary behavior.

Acclimation Training Improves Endurance Cycling Performance in the Heat without Inducing Endotoxemia

Article

Full-text available

Jul 2016

Purpose: While the intention of endurance athletes undertaking short term heat training protocols is to rapidly gain meaningful physical adaption prior to competition in the heat, it is currently unclear whether or not this process also presents an overt, acute challenge to the immune system. The aim of this study was therefore to examine the effects of heat training on both endurance performance and biomarkers associated with inflammatory and immune system responses. Methods: Moderately-actively males (n = 24) were allocated randomly to either HOT (n = 8, 35°C, and 70% RH; NEUTRAL (n = 8, 20°C, and 45% RH); or a non-exercising control group, (CON, n = 8). Over the 18 day study HOT and NEUTRAL performed seven training sessions (40 min cycling at 55 of VO2 max) and all participants completed three heat stress tests (HST) at 35°C and 70% RH. The HST protocol comprised three × sub-maximal intervals followed by a 5 km time trial on a cycle ergometer. Serum samples were collected before and after each HST and analyzed for interleukin-6, immunoglobulin M and lipopolysaccharide. Results: Both HOT and NEUTRAL groups experienced substantial improvement to 5 km time trial performance (HOT -33 ± 20 s, p = 0.02, NEUTRAL -39 ± 18 s, p = 0.01) but only HOT were faster (-45 ± 25 s, and -12 s ± 7 s, p = 0.01) in HST3 compared to baseline and HST2. Interleukin-6 was elevated after exercise for all groups however there were no significant changes for immunoglobulin M or lipopolysaccharide. Conclusions: Short-term heat training enhances 5 km cycling time trial performance in moderately-fit subjects by ~6%, similar in magnitude to exercise training in neutral conditions.Three top-up training sessions yielded a further 3% improvement in performance for the HOT group. Furthermore, the heat training did not pose a substantial challenge to the immune system.

Can exercise affect the course of inflammatory bowel disease? Experimental and clinical evidence

Article

Full-text available

May 2016

The inflammatory bowel disease (IBD) consisting of Crohn's disease (CD) and ulcerative colitis (UC) are defined as idiopathic, chronic and relapsing intestinal disorders occurring in genetically predisposed individuals exposed to environmental risk factors such as diet and microbiome changes. Since conventional drug therapy is expensive and not fully efficient, there is a need for alternative remedies that can improve the outcome in patients suffering from IBD. Whether exercise, which has been proposed as adjunct therapy in IBD, can be beneficial in patients with IBD remains an intriguing question. In this review, we provide an overview of the effects of exercise on human IBD and experimental colitis in animal models that mimic human disease, although the information on exercise in human IBD are sparse and poorly understood. Moderate exercise can exert a beneficial ameliorating effect on IBD and improve the healing of experimental animal colitis due to the activity of protective myokines such as irisin released from working skeletal muscles. CD patients with higher levels of exercise were significantly less likely to develop active disease at six months. Moreover, voluntary exercise has been shown to exert a positive effect on IBD patients’ mood, weight maintenance and osteoporosis. On the other hand, depending on its intensity and duration, exercise can evoke transient mild systemic inflammation and enhances pro-inflammatory cytokine release, thereby exacerbating the gastrointestinal symptoms. We discuss recent advances in the mechanism of voluntary and strenuous exercise affecting the outcome of IBD in patients and experimental animal models.

Case Study: Utilizing a Low FODMAP Diet to Combat Exercise-Induced Gastrointestinal Symptoms

Article

Full-text available

Apr 2016
INT J SPORT NUTR EXE

Athletes employ various dietary strategies in attempts to attenuate exercise-induced gastrointestinal (GI) symptoms to ensure optimal performance. This case-study outlines one of these GI-targeted approaches via the implementation of a short-term low FODMAP (Fermentable Oligosaccharides, Disaccharides, Monosaccharides and Polyols) diet, with the aim to attenuate persistent running specific GI symptoms in a recreationally competitive multisport athlete (male, 86 kg, 57.9 ml.kg.min-1 VO2max, 10-15 hrs.week-1 training, with no diagnosed GI disorder). Using a single-blinded approach a habitual diet was compared to a 6-day low FODMAP intervention diet (81 ± 5g vs 7.2 ± 5.7g FODMAPs.day-1) for their effect on GI symptoms and perceptual wellbeing. Training was similar during the habitual and dietary intervention periods. Post-exercise (During) GI symptom ratings were recorded immediately following training. Daily GI symptoms and the Daily Analysis of Life Demands for Athletes (DALDA) were recorded at the end of each day. Daily and During GI symptom scores (scale 0-9) ranged from 0-4 during the habitual dietary period while during the low FODMAP dietary period all scores were 0 (no symptoms at all). DALDA scores for 'worse than normal' ranged from 3-10 vs 0-8 in the habitual and low FODMAP dietary periods, respectively, indicating improvement. This intervention was effective for this GI symptom prone athlete; however, randomized-controlled trials are required to assess the suitability of low FODMAP diets for reducing GI distress in other symptomatic athletes.

Nutrition and Athletic Performance

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Mar 2016
MED SCI SPORT EXER

It is the position of the Academy of Nutrition and Dietetics, Dietitians of Canada, and the American College of Sports Medicine that the performance of, and recovery from, sporting activities are enhanced by well-chosen nutrition strategies. These organizations provide guidelines for the appropriate type, amount, and timing of intake of food, fluids, and supplements to promote optimal health and performance across different scenarios of training and competitive sport. This position paper was prepared for members of the Academy of Nutrition and Dietetics, Dietitians of Canada (DC), and American College of Sports Medicine (ACSM), other professional associations, government agencies, industry, and the public. It outlines the Academy’s, DC’s and ACSM’s stance on nutrition factors that have been determined to influence athletic performance and emerging trends in the field of sports nutrition. Athletes should be referred to a registered dietitian/nutritionist for a personalized nutrition plan. In the United States and in Canada, the Certified Specialist in Sports Dietetics (CSSD) is a registered dietitian/nutritionist and a credentialed sports nutrition expert.

Life and death at the mucosal-luminal interface: New perspectives on human intestinal ischemia-reperfusion

Article

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Mar 2016
WORLD J GASTROENTERO

phenomenon. Morbidity and mortality rates are extraordinarily high and did not improve over the past decades. This is in part attributable to limited knowledge on the pathophysiology of intestinal ischemia-reperfusion (IR) in man, the paucity in preventive and/or therapeutic options and the lack of early diagnostic markers for intestinal ischemia. To improve our knowledge and solve clinically important questions regarDing intestinal IR, we developed a human experimental intestinal IR model. With this model, we were able to gain insight into the mechanisms that allow the human gut to withstand short periods of IR without the development of severe inflammatory responses. The purpose of this review is to overview the most relevant recent advances in our understanDing of the pathophysiology of human intestinal IR, as well as the (potential) future clinical implications.

Oral versus intravenous iron replacement therapy distinctly alters the gut microbiota and metabolome in patients with IBD

Article

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Feb 2016
GUT

Objective Iron deficiency is a common complication in patients with IBD and oral iron therapy is suggested to exacerbate IBD symptoms. We performed an open-labelled clinical trial to compare the effects of per oral (PO) versus intravenous (IV) iron replacement therapy (IRT). Design The study population included patients with Crohn's disease (CD; N=31), UC (N=22) and control subjects with iron deficiency (non-inflamed, NI=19). After randomisation, participants received iron sulfate (PO) or iron sucrose (IV) over 3 months. Clinical parameters, faecal bacterial communities and metabolomes were assessed before and after intervention. Results Both PO and IV treatments ameliorated iron deficiency, but higher ferritin levels were observed with IV. Changes in disease activity were independent of iron treatment types. Faecal samples in IBD were characterised by marked interindividual differences, lower phylotype richness and proportions of Clostridiales. Metabolite analysis also showed separation of both UC and CD from control anaemic participants. Major shifts in bacterial diversity occurred in approximately half of all participants after IRT, but patients with CD were most susceptible. Despite individual-specific changes in phylotypes due to IRT, PO treatment was associated with decreased abundances of operational taxonomic units assigned to the species Faecalibacterium prausnitzii, Ruminococcus bromii, Dorea sp. and Collinsella aerofaciens. Clear IV-specific and PO-specific fingerprints were evident at the level of metabolomes, with changes affecting cholesterol-derived host substrates. Conclusions Shifts in gut bacterial diversity and composition associated with iron treatment are pronounced in IBD participants. Despite similar clinical outcome, oral administration differentially affects bacterial phylotypes and faecal metabolites compared with IV therapy. Trial registration number clinicaltrial.gov (NCT01067547).

The Impact of Gastrointestinal Symptoms and Dermatological Injuries on Nutritional Intake and Hydration Status During Ultramarathon Events

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Jan 2016

Background: Debilitating gastrointestinal symptoms (GIS) and dermatological injuries (DI) are common during and after endurance events and have been linked to performance decrements, event withdrawal, and issues requiring medical attention. The study aimed to determine whether GIS and DI affect food and fluid intake, and nutritional and hydration status, of ultramarathon runners during multi-stage (MSUM) and 24-h continuous (24 h) ultramarathons. Methods: Ad libitum food and fluid intakes of ultramarathon runners (MSUM n = 54; 24 h n = 22) were recorded throughout both events and analysed by dietary analysis software. Body mass and urinary ketones were determined, and blood samples were taken, before and immediately after running. A medical log was used to monitor symptoms and injuries throughout both events. Results: GIS were reported by 85 and 73 % of ultramarathon runners throughout MSUM and 24 h, respectively. GIS during MSUM were associated with reduced total daily, during, and post-stage energy and macronutrient intakes (p < 0.05), whereas GIS during 24 h did not alter nutritional variables. Throughout the MSUM 89 % of ultramarathon runners reported DI. DI during MSUM were associated with reduced carbohydrate (p < 0.05) intake during running and protein intake post-stage (p < 0.05). DI during 24 h were low; thus, comparative analyses were not possible. Daily, during running, and post-stage energy, macronutrient and water intake variables were observed to be lower with severity of GIS and DI (p < 0.05) throughout the MSUM only. Conclusions: GIS during the MSUM, but not the 24 h, compromised nutritional intake. DI presence and severity also compromised nutrient intake during running and recovery in the MSUM.

Intestinal epithelial barrier function and tight junction proteins with heat and exercise

Article

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Sep 2015
J APPL PHYSIOL

A single layer of enterocytes and tight junctions (intercellular multiprotein complexes) form the intestinal epithelial barrier that controls transport of molecules through transcellular and paracellular pathways. Dysfunctional or "leaky" intestinal tight junction barrier allows augmented permeation of luminal antigens, endotoxins, and bacteria to the blood stream. Various substances and conditions have been shown to affect the maintenance of the intestinal epithelial tight junction barrier. The primary focus of the present review is to analyze the effects of the exertional or non-exertional (passive hyperthermia) heat stress on tight junction barrier function in in-vitro and in-vivo (animals and humans) models. Our secondary focus is to review changes in tight junction proteins in response to exercise or hyperthermic conditions. Finally, we discuss some pharmacological or nutritional interventions providing direct insights into the cellular mechanisms involved in maintaining homeostasis of the intestinal epithelial tight junction barrier during heat stress or exercise.

Cytokine expression and secretion by skeletal muscle cells: regulatory mechanisms and exercise effects

Article

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Apr 2015
EXERC IMMUNOL REV

Cytokines are important mediators of various aspects of health and disease, including appetite, glucose and lipid metabolism, insulin sensitivity, skeletal muscle hypertrophy and atrophy. Over the past decade or so, considerable attention has focused on the potential for regular exercise to counteract a range of disease states by modulating cytokine production. Exercise stimulates moderate to large increases in the circulating concentrations of interleukin (IL)-6, IL-8, IL- 10, IL-1 receptor antagonist, granulocyte-colony stimulating factor, and smaller increases in tumor necrosis factor-α, monocyte chemotactic protein-1, IL-1β, brain-derived neurotrophic factor, IL-12p35/p40 and IL-15. Although many of these cytokines are also expressed in skeletal muscle, not all are released from skeletal muscle into the circulation during exercise. Conversely, some cytokines that are present in the circulation are not expressed in skeletal muscle after exercise. The reasons for these discrepant cytokine responses to exercise are unclear. In this review, we address these uncertainties by summarizing the capacity of skeletal muscle cells to produce cytokines, analyzing other potential cellular sources of circulating cytokines during exercise, and discussing the soluble factors and intracellular signaling pathways that regulate cytokine synthesis (e.g., RNA-binding proteins, microRNAs, suppressor of cytokine signaling proteins, soluble receptors). Copyright © 2015 International Society of Exercise and Immunology. All rights reserved.

Statement of the Third International Exercise-Associated Hyponatremia Consensus Development Conference, Carlsbad, California, 2015

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Jul 2015

The Impact of a Ten-Week Physical Exercise Program on Health-Related Quality of Life in Patients with Inflammatory Bowel Disease: A Prospective Randomized Controlled Trial

Article

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Mar 2015
DIGESTION

Improving health-related quality of life is a primary target of therapy for patients with inflammatory bowel disease. Physical activity has been demonstrated to improve health-related quality of life in several patient populations with chronic disease. There are very few studies investigating the effects of physical activity on health-related quality of life in inflammatory bowel disease. The primary purpose of this study is to investigate the effects of 10 weeks of moderate physical activity on health-related quality of life in patients with inflammatory bowel disease. Thirty patients with mild to moderate IBD (Crohn's Disease Activity Index (CDAI) <220 or Rachmilewitz Index (RI) <11) were randomized 1:1 to either supervised moderate-intensity running thrice a week for 10 weeks or a control group who were not prescribed any exercise. Health-related quality of life, symptoms, and inflammation were assessed at baseline and after 10 weeks. Participants were 41 ± 14 years (73% female), had a body mass index of 22.8 ± 4.1 kg/m(2), and an average CDAI or RI of 66.8 ± 42.4 and 3.6 ± 3.1. No adverse events occurred during the 10-week training period. Health-related quality of life, reported as IBDQ total score, improved 19% in the intervention group and 8% in the control group. Scores for the IBDQ social sub-scale were significantly improved in the intervention group compared with controls (ΔIBDQsocial = 6.27 ± 5.46 vs. 1.87 ± 4.76, p = 0.023). Patients suffering from moderately active IBD are capable of performing symptom-free regular endurance exercise. Our data support the assumption that PA is feasible in IBD patients. PA may furthermore improve quality of life through improvements in social well-being, and may, therefore, be a useful adjunct to IBD therapy. © 2015 S. Karger AG, Basel.

Gastrointestinal distress is common during a 161-km ultramarathon

Article

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Feb 2015

This study examined the incidence, severity, and timing of gastrointestinal (GI) symptoms in finishers and non-finishers of the 161-km Western States Endurance Run. A total of 272 runners (71.0% of starters) completed a post-race questionnaire that assessed the incidence and severity (none = 0, mild = 1, moderate = 2, severe = 3, very severe = 4) of 12 upper (reflux/heartburn, belching, stomach bloating, stomach cramps/pain, nausea, vomiting) and lower (intestinal cramps/pain, flatulence, side ache/stitch, urge to defecate, loose stool/diarrhoea, intestinal bleeding/bloody faeces) GI symptoms experienced during each of four race segments. GI symptoms were experienced by most runners (96.0%). Flatulence (65.9% frequency, mean value 1.0, s = 0.6 severity), belching (61.3% frequency, mean value 1.0, s = 0.6 severity), and nausea (60.3% frequency, mean value 1.0, s = 0.7 severity) were the most common symptoms. Among race finishers, 43.9% reported that GI symptoms affected their race performance, with nausea being the most common symptom (86.0%). Among race non-finishers, 35.6% reported that GI symptoms were a reason for dropping out of the race, with nausea being the most common symptom (90.5%). For both finishers and non-finishers, nausea was greatest during the most challenging and hottest part of the race. GI symptoms are very common during ultramarathon running, and in particular, nausea is the most common complaint for finishers and non-finishers.

Circulatory endotoxin concentration and cytokine profile in response to exertional-heat stress during a multi-stage ultra-marathon competition

Article

Full-text available

Feb 2015
EXERC IMMUNOL REV

Exertional-heat stress has the potential to disturb intestinal integrity, leading to enhanced permeability of enteric pathogenic micro-organisms and associated clinical manifestations. The study aimed to determine the circulatory endotoxin concentration and cytokine profile of ultra-endurance runners (UER, n=19) and a control group (CON, n=12) during a five stage 230km ultra-marathon (mean ± SD: 27h38min ± 3h55min) conducted in hot and dry environmental conditions (30ºC to 40ºC and 31% to 40% relative humidity). Body mass and tympanic temperature were measured, and venous blood samples were taken before (pre-stage) and immediately after (post-stage) each stage of the ultra-marathon for the analysis of gram-negative bacterial endotoxin, C-reactive protein, cytokine profile (IL-6, IL-1β, TNF-α, IFN-γ, IL-10, and IL- 1ra), and plasma osmolality. Gastrointestinal symptoms and perceptive thermal tolerance rating were also monitored throughout competition. Mean exercise-induced body mass loss over the five stages ranged 1.0% to 2.5%. Pre- and poststage plasma osmolality in UER ranged277 to 282mOsmol/kg and 286 to 297 mOsmol/kg, respectively. Pre-stage concentrations of endotoxin (peak: 21% at Stage 5), C-reactive protein (889% at Stage 3), IL-6 (152% at Stage 2), IL-1β (95% at Stage 5), TNF-α (168% at Stage 5), IFN-γ (102% at Stage 5),IL-10 (1271% at Stage 3), and IL-1ra (106% at Stage 5) increased as the ultra-marathon progressed in UER; while no changes in CON were observed (except for IL-1β, 71% at Stage 5). Pre- to post-stage increases were observed for endotoxin (peak: 22% at Stage 3), C-reactive protein (25% at Stage 1), IL-6 (238% at Stage 1), IL-1β (64% at Stage 1), TNF-α (101% at Stage 1), IFN-γ (39% at Stage 1), IL-10 (1100% at Stage 1), and IL-1ra(207% at Stage 1) concentrations in UER. Multi-stage ultra-marathon competition in the heat resulted in a modest circulatory endotoxaemia accompanied by a pronounced pro-inflammatory cytokinaemia by post-Stage 1, both of which were sustained throughout competition at rest (pre-stage) and after stage completion. Compensatory anti-inflammatory responses and other external factors (i.e., training status, cooling strategies, heat acclimatization, nutrition and hydration) may have contributed towards limiting the extent of pro-inflammatory responses in the current scenario. Copyright © 2015 International Society of Exercise and Immunology. All rights reserved.

Systemic LPS and Inflammatory Response during Consecutive Days of Exercise in Heat

Article

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Dec 2014

This investigation studied circulating LPS activity, potential intestinal damage, and the systemic inflammatory response (SIR) during the exercise heat acclimation process. 8 healthy males (Age=24±3 years) ran in a hot environment on 5 consecutive days until core temperature (Tc) was elevated 2°C above rest. Plasma was obtained pre-, post-, 1 h post-, and 3 h post-exercise on the 1(st), 3(rd), and 5(th) day of exercise and analyzed for TNF-α, IL-6, IL-10, IL-1ra, LPS, and intestinal fatty acid-binding protein (I-FABP). Plasma LPS (1.1 EU·ml(-1)±0.1 vs. 0.7 EU·ml(-1)±0.03; P<0.01) and I-FABP (930.7 pg·ml(-1)±149.0 vs. 640.2 pg·ml(-1)±125.0; P<0.001) were significantly increased post-exercise each. The SIR remained largely unchanged during the study except for TNF-α. Plasma TNF-α was significantly lower on Day 5 at 1 h (3.2 pg·ml(-1)±0.6 vs. 4.5 pg·ml(-1)±0.8; P=0.01) and 3 h (3.6 pg·ml(-1)±0.8 vs. 4.8 pg·ml(-1)±0.9; P=0.05) post-exercise as compared to Day 1. Findings indicate that adaptations to exercise in the heat resulting in reductions of intestinal damage and plasma LPS activity require longer time periods in moderately trained males. © Georg Thieme Verlag KG Stuttgart · New York.

Central Nervous System Control of Gastrointestinal Motility and Secretion and Modulation of Gastrointestinal Functions

Article

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Oct 2014

Although the gastrointestinal (GI) tract possesses intrinsic neural plexuses that allow a significant degree of autonomy over GI functions, the central nervous system (CNS) provides extrinsic neural inputs that regulate, modulate, and control these functions. While the intestines are capable of functioning in the absence of extrinsic inputs, the stomach and esophagus are much more dependent upon extrinsic neural inputs, particularly from parasympathetic and sympathetic pathways. The sympathetic nervous system exerts a predominantly inhibitory effect upon GI muscle and provides a tonic inhibitory influence over mucosal secretion while, at the same time, regulates GI blood flow via neurally mediated vasoconstriction. The parasympathetic nervous system, in contrast, exerts both excitatory and inhibitory control over gastric and intestinal tone and motility. Although GI functions are controlled by the autonomic nervous system and occur, by and large, independently of conscious perception, it is clear that the higher CNS centers influence homeostatic control as well as cognitive and behavioral functions. This review will describe the basic neural circuitry of extrinsic inputs to the GI tract as well as the major CNS nuclei that innervate and modulate the activity of these pathways. The role of CNS-centered reflexes in the regulation of GI functions will be discussed as will modulation of these reflexes under both physiological and pathophysiological conditions. Finally, future directions within the field will be discussed in terms of important questions that remain to be resolved and advances in technology that may help provide these answers. © 2014 American Physiological Society. Compr Physiol 4: 1339-1368, 2014.

Acute Exercise and Gastric Emptying: A Meta-Analysis and Implications for Appetite Control

Article

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Nov 2014

Background: Gastric emptying (GE) could influence exercise-induced changes in appetite and energy intake. GE also could contribute to changes in gastric symptoms and the availability of nutrients during exercise, which will subsequently affect performance. Objective: The objective of this review was to determine the effects of acute exercise on GE using a systematic review and meta-analysis. The most common parameters to determine GE were selected, consisting of half-emptying time and volume emptied. Oral-caecal transit time (OCTT) was also examined. Data sources: Research databases (PubMed, Scopus, Google Scholar, EBSCOhost, SPORTDiscus) were searched through November 2013 for original studies, abstracts, theses and dissertations that examined the influence of acute exercise on GE. Study selection: Studies were included if they evaluated GE or OCTT during and/or after exercise and involved a resting control trial. Study appraisal and synthesis: Initially, 195 studies were identified. After evaluation of study characteristics and quality and validity, data from 20 studies (35 trials) involving 221 participants (157 men; 52 women; 12 unknown) were extracted for meta-analysis. Random-effects meta-analyses were utilised for the three main outcome variables, and effect sizes (ES) are reported as Hedge's g due to numerous small sample sizes. Results: Random-effects modelling revealed non-significant and small/null main effect sizes for volume emptied (ES = 0.195; 95% CI -0.25 to 0.64), half-time (ES = -0.109, 95% CI -0.66 to 0.44) and OCTT (ES = 0.089; 95% CI -0.64 to 0.82). All analyses exhibited significant heterogeneity and numerous variables moderated the results. There was a dose response of exercise intensity; at lower intensities GE was faster, and at high exercise intensities GE was slower. Walking was associated with faster GE and cycling with slower GE. Greater volume of meal/fluid ingested, higher osmolality of beverage and longer exercise duration were also associated with slower GE with exercise. Limitations: The major limitation is that the majority of studies utilised a liquid bolus administered pre-exercise to determine GE; the relationship to post-exercise appetite and energy intake remains unknown. Study populations were also generally active or trained individuals. Furthermore, our review was limited to English language studies and studies that utilised resting control conditions. Conclusions: These results suggest that exercise intensity, mode, duration and the nature of meal/fluid ingested all influence GE during and after acute exercise. The relationship of GE parameters with appetite regulation after exercise remains largely unexplored. Further integrative studies combining GE and alterations in gut hormones, as well as in populations such as overweight and obese individuals are needed.

Bovine colostrum, training status, and gastrointestinal permeability during exercise in the heat: A placebo-controlled double-blind study

Article

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Jun 2014

Heat stress can increase gastrointestinal permeability, allowing ingress of gram-negative bacterial fragments and thus potentially inflammation and ultimately endotoxemia. Permeability may rise with intense exercise, yet some data indicate that endotoxemia may be mitigated with bovine colostrum supplementation. Using a double-blind, randomised, placebo-controlled crossover study, we tested whether bovine colostrum (COL; 1.7 g·kg(-1)·day(-1) for 7 days) would attenuate physiological strain and aid exercise capacity in the heat, especially in untrained individuals. Seven trained men (T; peak oxygen uptake 64 ± 4 mL·kg(-1)·min(-1)) and 8 untrained men (UT, peak oxygen uptake 46 ± 4 mL·kg(-1)·min(-1)) exercised for 90 min in 30 °C (50 % relative humidity) after COL or placebo (corn flour). Exercise consisted of 15-min cycling at 50 % heart rate reserve (HRR) before and after 60 min of running (30 min at 80 % HRR then 30-min distance trial). Heart rate, blood pressure (Finometer), esophageal, and skin temperatures were recorded continuously. Gastrointestinal permeability was assessed from urine (double-sugar model, using high-performance liquid chromatography) and blood (intestinal fatty acid-binding protein, I-FABP). The T group ran ∼2.4 km (35%) further than the UT group in the distance trial, and I-FABP increased more in the T group than in the UT group, but physiological and performance outcomes were unaffected by colostrum supplementation, irrespective of fitness. Circulating pro- and anti-inflammatory cytokine concentrations were higher following exercise, but were not modulated by fitness or COL. Despite substantial thermal and cardiovascular strain incurred in environmental conditions in which exertional endotoxemia may occur, bovine colostrum supplementation had no observable benefit on the physiology or performance of either highly trained endurance athletes or untrained individuals.

The effects of acute oral glutamine supplementation on exercise-induced gastrointestinal permeability and heat shock protein expression in peripheral blood mononuclear cells

Article

Full-text available

Jul 2014

Chronic glutamine supplementation reduces exercise-induced intestinal permeability and inhibits the NF-κB pro-inflammatory pathway in human peripheral blood mononuclear cells. These effects were correlated with activation of HSP70. The purpose of this paper is to test if an acute dose of oral glutamine prior to exercise reduces intestinal permeability along with activation of the heat shock response leading to inhibition of pro-inflammatory markers. Physically active subjects (N = 7) completed baseline and exercise intestinal permeability tests, determined by the percent ratio of urinary lactulose (5 g) to rhamnose (2 g). Exercise included two 60-min treadmill runs at 70 % of VO2max at 30 °C after ingestion of glutamine (Gln) or placebo (Pla). Plasma levels of endotoxin and TNF-α, along with peripheral blood mononuclear cell (PBMC) protein expression of HSP70 and IκBα, were measured pre- and post-exercise and 2 and 4 h post-exercise. Permeability increased in the Pla trial compared to that at rest (0.06 ± 0.01 vs. 0.02 ± 0.018) and did not increase in the Gln trial. Plasma endotoxin was lower at the 4-h time point in the Gln vs. 4 h in the Pla (6.715 ± 0.046 pg/ml vs. 7.952 ± 1.11 pg/ml). TNF-α was lower 4 h post-exercise in the Gln vs. Pla (1.64 ± 0.09 pg/ml vs. 1.87 ± 0.12 pg/ml). PBMC expression of IkBα was higher 4 h post-exercise in the Gln vs. 4 h in the Pla (1.29 ± 0.43 vs. 0.8892 ± 0.040). HSP70 was higher pre-exercise and 2 h post-exercise in the Gln vs. Pla (1.35 ± 0.21 vs. 1.000 ± 0.000 and 1.65 ± 0.21 vs. 1.27 ± 0.40). Acute oral glutamine supplementation prevents an exercise-induced rise in intestinal permeability and suppresses NF-κB activation in peripheral blood mononuclear cells.

Diets that differ in their FODMAP content alter the colonic luminal microenvironment

Article

Full-text available

Jul 2014

Objective A low FODMAP (Fermentable Oligosaccharides, Disaccharides, Monosaccharides And Polyols) diet reduces symptoms of IBS, but reduction of potential prebiotic and fermentative effects might adversely affect the colonic microenvironment. The effects of a low FODMAP diet with a typical Australian diet on biomarkers of colonic health were compared in a single-blinded, randomised, cross-over trial. Design Twenty-seven IBS and six healthy subjects were randomly allocated one of two 21-day provided diets, differing only in FODMAP content (mean (95% CI) low 3.05 (1.86 to 4.25) g/day vs Australian 23.7 (16.9 to 30.6) g/day), and then crossed over to the other diet with ≥21-day washout period. Faeces passed over a 5-day run-in on their habitual diet and from day 17 to day 21 of the interventional diets were pooled, and pH, short-chain fatty acid concentrations and bacterial abundance and diversity were assessed. Results Faecal indices were similar in IBS and healthy subjects during habitual diets. The low FODMAP diet was associated with higher faecal pH (7.37 (7.23 to 7.51) vs 7.16 (7.02 to 7.30); p=0.001), similar short-chain fatty acid concentrations, greater microbial diversity and reduced total bacterial abundance (9.63 (9.53 to 9.73) vs 9.83 (9.72 to 9.93) log10 copies/g; p<0.001) compared with the Australian diet. To indicate direction of change, in comparison with the habitual diet the low FODMAP diet reduced total bacterial abundance and the typical Au

Systematic review: Exercise-induced gastrointestinal syndrome-implications for health and intestinal disease

Abstract

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