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Rosbrook P, Margolis LM, Pryor JL. Nutritional Considerations in Exercise-Based Heat Acclimation: A Narrative Review. Sports Med 2024:10.1007/s40279-024-02109-x. [PMID: 39217233 DOI: 10.1007/s40279-024-02109-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/15/2024] [Indexed: 09/04/2024]
Abstract
In addition to its established thermoregulatory and cardiovascular effects, heat stress provokes alterations in macronutrient metabolism, gastrointestinal integrity, and appetite. Inadequate energy, carbohydrate, and protein intake have been implicated in reduced exercise and heat tolerance. Classic exercise heat acclimation (HA) protocols employ low-to-moderate-intensity exercise for 5-14 days, while recent studies have evolved the practice by implementing high-intensity and task-specific exercise during HA, which potentially results in impaired post-HA physical performance despite adequate heat adaptations. While there is robust literature demonstrating the performance benefit of various nutritional interventions during intensive training and competition, most HA studies implement few nutritional controls. This review summarizes the relationships between heat stress, HA, and intense exercise in connection with substrate metabolism, gastrointestinal function, and the potential consequences of reduced energy availability. We discuss the potential influence of macronutrient manipulations on HA study outcomes and suggest best practices to implement nutritional controls.
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Affiliation(s)
- Paul Rosbrook
- Center for Research & Education in Special Environments, Department of Exercise & Nutrition Sciences, State University of New York University at Buffalo, Buffalo, NY, USA.
| | - Lee M Margolis
- Military Nutrition Division, U.S. Army Research Institute for Environmental Medicine, Natick, MA, USA
| | - J Luke Pryor
- Center for Research & Education in Special Environments, Department of Exercise & Nutrition Sciences, State University of New York University at Buffalo, Buffalo, NY, USA
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Ulluwishewa D, Nicholls G, Henderson H, Bernstein D, Fraser K, Barnett MPG, Barnes MJ. Effects of bovine whey protein on exercise-induced gut permeability in healthy adults: a randomised controlled trial. Eur J Appl Physiol 2024; 124:2045-2056. [PMID: 38386104 PMCID: PMC11199293 DOI: 10.1007/s00421-024-05423-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2023] [Accepted: 01/16/2024] [Indexed: 02/23/2024]
Abstract
PURPOSE Intestinal permeability is a critical component of gut barrier function. Barrier dysfunction can be triggered by certain stressors such as exercise, and if left unmanaged can lead to local and systemic disorders. The aim of this study was to investigate the effects of a specific whey protein fraction in alleviating exercise-induced gut permeability as assessed by recovery of lactulose/rhamnose (L/R) and lactulose/mannitol (L/M) urinary probes. METHODS Eight males and eight females (aged 18-50) completed two arms of a double-blind, placebo-controlled, crossover study. For each arm participants performed two baseline intestinal permeability assessments, following which they consumed the treatment (2 g/day of milk powder containing 200 mg of whey protein) or placebo (2 g/day of milk powder) for 14 days, before performing a post-exercise permeability assessment. The exercise protocol involved a 20-min run at 80% of maximal oxygen uptake on a 1% incline. RESULTS Mixed model analysis revealed an increase in L/R (23%; P < 0.001) and L/M (20%; P < 0.01) recovery following exercise. However, there was no treatment or treatment × exercise effect. CONCLUSION The exercise protocol utilised in our study induces gut permeability. However, consuming whey protein, at the dose and timing prescribed, is not able to mitigate this effect.
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Affiliation(s)
| | - Grayson Nicholls
- School of Sport, Exercise and Nutrition, Massey University, Palmerston North, New Zealand
| | | | | | - Karl Fraser
- AgResearch, Te Ohu Rangahau Kai, Palmerston North, New Zealand
| | - Matthew P G Barnett
- AgResearch, Te Ohu Rangahau Kai, Palmerston North, New Zealand
- Riddet Institute, Palmerston North, New Zealand
| | - Matthew J Barnes
- School of Sport, Exercise and Nutrition, Massey University, Palmerston North, New Zealand
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3
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Chantler S, Wood-Martin R, Holliday A, Davison G, Crabtree DR, Readhead C, Jones B. The Frequency and Severity of Gastrointestinal Symptoms in Rugby Players. Int J Sports Med 2024; 45:323-221. [PMID: 38272040 DOI: 10.1055/a-2206-4751] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2024]
Abstract
This study aimed to assess the self-reported frequency and severity of gastrointestinal symptoms (GIS) at rest and around rugby training and match play in male and female rugby union players. An online questionnaire was sent to registered rugby union players (sevens or fifteens). Thirteen GIS were assessed alongside perceptions of appetite around rugby and rest using Likert and visual analog scales. Questions investigating a range of medical and dietary factors were included. Three hundred and twenty-five players (male n=271, female n=54) participated in the study. More frequent GIS (at least one GIS experienced weekly/more often) was reported by players at rest (n=203; 62%) compared to around rugby (n=154; 47%). The overall severity of GIS was low (mild discomfort), but a portion of players (33%) did report symptoms of moderate severity around rugby. Female players reported more frequent and severe symptoms compared to male counterparts (p<0.001). Self-reported appetite was significantly lower after matches compared to training. There were no dietary or medical factors associated with GIS severity scores. This study describes GIS characteristics in male and female rugby union players. Half of the players assessed experienced some form of GIS that may affect nutrition, training, or performance, and should thus be a consideration for practitioners supporting this cohort.
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Affiliation(s)
- Sarah Chantler
- Carnegie School of Sport, Leeds Beckett University, Leeds, United Kingdom of Great Britain and Northern Ireland
| | | | - Adrian Holliday
- Physiology, University of Newcastle upon Tyne, Newcastle upon Tyne, United Kingdom of Great Britain and Northern Ireland
| | - Glen Davison
- Centre for Sports Studies, University of Kent, Canterbury, United Kingdom of Great Britain and Northern Ireland
| | - Daniel R Crabtree
- The Rowett Institute, School of Medicine, Medical Sciences and Nutrition, University of Aberdeen, Aberdeen, United Kingdom of Great Britain and Northern Ireland
| | - Clint Readhead
- Head of Medical services, South African Rugby Union, Newlands, South Africa
| | - Ben Jones
- Carnegie School of Sport, Leeds Beckett University, Leeds, United Kingdom of Great Britain and Northern Ireland
- Carnegie School of Sport, Leeds Beckett University, Leeds, United Kingdom of Great Britain and Northern Ireland
- Carnegie School of Sport, Leeds Beckett University, Leeds, United Kingdom of Great Britain and Northern Ireland
- Carnegie School of Sport, Leeds Beckett University, Leeds, United Kingdom of Great Britain and Northern Ireland
- Carnegie School of Sport, Leeds Beckett University, Leeds, United Kingdom of Great Britain and Northern Ireland
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Houghton MJ, Snipe RMJ, Williamson G, Costa RJS. Plasma measurements of the dual sugar test reveal carbohydrate immediately alleviates intestinal permeability caused by exertional heat stress. J Physiol 2023; 601:4573-4589. [PMID: 37695123 DOI: 10.1113/jp284536] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2023] [Accepted: 08/18/2023] [Indexed: 09/12/2023] Open
Abstract
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%V ̇ O 2 max ${\dot V_{{{\mathrm{O}}_{\mathrm{2}}}{\mathrm{max}}}}$ in temperate, warm and hot ambient conditions, and/or experimental trial B (ET-B; n = 9), consisting of 2 h running at 60%V ̇ O 2 max ${\dot V_{{{\mathrm{O}}_{\mathrm{2}}}{\mathrm{max}}}}$ 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. 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.
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Affiliation(s)
- Michael J Houghton
- Department of Nutrition, Dietetics and Food, School of Clinical Sciences at Monash Health, Faculty of Medicine, Nursing and Health Sciences, Monash University, Notting Hill, Victoria, Australia
- Victorian Heart Institute, Monash University, Clayton, Victoria, Australia
| | - Rhiannon M J Snipe
- Centre for Sport Research, School of Exercise and Nutrition Sciences, Deakin University, Burwood, Victoria, Australia
| | - Gary Williamson
- Department of Nutrition, Dietetics and Food, School of Clinical Sciences at Monash Health, Faculty of Medicine, Nursing and Health Sciences, Monash University, Notting Hill, Victoria, Australia
- Victorian Heart Institute, Monash University, Clayton, Victoria, Australia
| | - Ricardo J S Costa
- Department of Nutrition, Dietetics and Food, School of Clinical Sciences at Monash Health, Faculty of Medicine, Nursing and Health Sciences, Monash University, Notting Hill, Victoria, Australia
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King MA, Grosche A, Ward SM, Ward JA, Sasidharan A, Mayer TA, Plamper ML, Xu X, Ward MD, Clanton TL, Vidyasagar S. Amino acid solution mitigates hypothermia response and intestinal damage following exertional heat stroke in male mice. Physiol Rep 2023; 11:e15681. [PMID: 37217446 PMCID: PMC10202825 DOI: 10.14814/phy2.15681] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2023] [Revised: 04/11/2023] [Accepted: 04/13/2023] [Indexed: 05/24/2023] Open
Abstract
Increased gut permeability is implicated in the initiation and extent of the cytokine inflammatory response associated with exertional heat stroke (EHS). The primary objective of this study was to determine if a five amino acid oral rehydration solution (5AAS), specifically designed for the protection of the gastrointestinal lining, would prolong time to EHS, maintain gut function and dampen the systemic inflammatory response (SIR) measured during EHS recovery. Male C57/BL6J mice instrumented with radiotelemetry were gavaged with 150 μL of 5AAS or H2 O, and ≈12 h later were either exposed to an EHS protocol where mice exercised in a 37.5°C environmental chamber to a self-limiting maximum core temperature (Tc,max) or performed the exercise control (EXC) protocol (25°C). 5AAS pretreatment attenuated hypothermia depth and length (p < 0.005), which are indicators of EHS severity during recovery, without any effect on physical performance or thermoregulatory responses in the heat as determined by percent body weight lost (≈9%), max speed (≈6 m/min), distance (≈700 m), time to Tc,max (≈160 min), thermal area (≈550°C∙min), and Tc,max (42.2°C). EHS groups treated with 5AAS showed a significant decrease in gut transepithelial conductance, decreased paracellular permeability, increased villus height, increased electrolyte absorption and changes in tight junction protein expression pattern suggestive of improved barrier integrity (p < 0.05). No differences were witnessed between EHS groups in acute phase response markers of liver, circulating SIR markers, or indicators of organ damage during recovery. These results suggest that a 5AAS improves Tc regulation during EHS recovery through maintaining mucosal function and integrity.
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Affiliation(s)
- Michelle A. King
- Thermal and Mountain Medicine DivisionUnited States Army Research Institute of Environmental MedicineNatickMassachusettsUSA
| | - Astrid Grosche
- Radiation OncologyUniversity of Florida College of MedicineGainesvilleFloridaUSA
| | - Shauna M. Ward
- Thermal and Mountain Medicine DivisionUnited States Army Research Institute of Environmental MedicineNatickMassachusettsUSA
| | - Jermaine A. Ward
- Thermal and Mountain Medicine DivisionUnited States Army Research Institute of Environmental MedicineNatickMassachusettsUSA
| | - Anusree Sasidharan
- Radiation OncologyUniversity of Florida College of MedicineGainesvilleFloridaUSA
| | - Thomas A. Mayer
- Thermal and Mountain Medicine DivisionUnited States Army Research Institute of Environmental MedicineNatickMassachusettsUSA
| | - Mark L. Plamper
- Thermal and Mountain Medicine DivisionUnited States Army Research Institute of Environmental MedicineNatickMassachusettsUSA
| | - Xiaodong Xu
- Radiation OncologyUniversity of Florida College of MedicineGainesvilleFloridaUSA
| | - Matthew D. Ward
- Thermal and Mountain Medicine DivisionUnited States Army Research Institute of Environmental MedicineNatickMassachusettsUSA
| | - Thomas L. Clanton
- Health and Human PerformanceUniversity of FloridaGainesvilleFloridaUSA
| | - Sadasivan Vidyasagar
- Radiation OncologyUniversity of Florida College of MedicineGainesvilleFloridaUSA
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Lu CC, Ke CY, Wu WT, Lee RP. L-Glutamine is better for treatment than prevention in exhaustive exercise. Front Physiol 2023; 14:1172342. [PMID: 37187963 PMCID: PMC10175630 DOI: 10.3389/fphys.2023.1172342] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2023] [Accepted: 04/18/2023] [Indexed: 05/17/2023] Open
Abstract
Introduction: Glutamine is known as the richest nonessential amino acid in the human body. The intake of glutamine is not only beneficial to nutrition but also reported to enhance inflammation reducing bioactivity in exercise. Although studies have demonstrated that glutamine is beneficial for exercise, the optimal intake timing remains unclear. This study examined whether the effects of glutamine on tissue damage and physiology differ between intake timings. Methods: Rats were divided into without L-glutamine supplementation (vehicle), with L-glutamine before exhaustive exercise (prevention), and with L-glutamine after exhaustive exercise (treatment) groups. Exhaustive exercise was induced by treadmill running and L-glutamine was given by oral feeding. The exhaustive exercise began at a speed of 10 miles/min and increased in increments of 1 mile/min, to a maximum running speed of 15 miles/min with no incline. The blood samples were collected before exhaustive exercise, 12 h and 24 h after exercise to compare the creatine kinase isozyme MM (CK-MM), red blood cell count and platelet count. The animals were euthanized on 24 h after exercise, and tissue samples were collected for pathological examination and scored the severity of organ injury from 0 to 4. Results: The CK-MM was elevated gradually after exercise in the vehicle group; however, CK-MM was decreased after L-glutamine supplementation in the treatment group. The treatment group had higher red blood cell count and platelet count than the vehicle and prevention group after exercise. In addition, the treatment group had less tissue injury in the cardiac muscles, and kidneys than prevention group. Conclusion: The therapeutic effect of L-glutamine after exhaustive exercise was more effective than preventive before exercise.
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Affiliation(s)
- Cheng-Chung Lu
- Institute of Medical Sciences, Tzu Chi University, Hualien, Taiwan
- Office of Physical Education, Hsing Wu University, New Taipei City, Taiwan
| | - Chun-Yen Ke
- Center for General Education, Cheng Shiu University, Kaohsiung, Taiwan
| | - Wen-Tien Wu
- Institute of Medical Sciences, Tzu Chi University, Hualien, Taiwan
- Department of Orthopedics, Hualien Tzu Chi Hospital, Buddhist Tzu Chi Medical Foundation, Hualien, Taiwan
- School of Medicine, Tzu Chi University, Hualien, Taiwan
| | - Ru-Ping Lee
- Institute of Medical Sciences, Tzu Chi University, Hualien, Taiwan
- *Correspondence: Ru-Ping Lee,
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Taylor G, Leonard A, Tang JCY, Dunn R, Fraser WD, Virgilio N, Prawitt J, Stevenson E, Clifford T. The effects of collagen peptides on exercise-induced gastrointestinal stress: a randomized, controlled trial. Eur J Nutr 2023; 62:1027-1039. [PMID: 36370176 PMCID: PMC9941265 DOI: 10.1007/s00394-022-03051-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2022] [Accepted: 11/03/2022] [Indexed: 11/13/2022]
Abstract
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: [Formula: see text]O2max, 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 [Formula: see text]O2max. 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.
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Affiliation(s)
- Guy Taylor
- grid.1006.70000 0001 0462 7212Institue of Population Health Sciences, Newcastle University, Newcastle, UK
| | - Amber Leonard
- grid.6571.50000 0004 1936 8542School of Sport, Exercise and Health Sciences, Loughborough University, Loughborough, LE11 3TU UK
| | - Jonathan C. Y. Tang
- grid.8273.e0000 0001 1092 7967Norwich Medical School, University of East Anglia, Norwich University Hospital Norfolk, Norfolk, UK
| | - Rachel Dunn
- grid.8273.e0000 0001 1092 7967Norwich Medical School, University of East Anglia, Norwich University Hospital Norfolk, Norfolk, UK
| | - William D. Fraser
- grid.8273.e0000 0001 1092 7967Norwich Medical School, University of East Anglia, Norwich University Hospital Norfolk, Norfolk, UK
| | | | | | - Emma Stevenson
- grid.1006.70000 0001 0462 7212Institue of Population Health Sciences, Newcastle University, Newcastle, UK
| | - Tom Clifford
- School of Sport, Exercise and Health Sciences, Loughborough University, Loughborough, LE11 3TU, UK.
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Qiu Y, Fernández-García B, Lehmann HI, Li G, Kroemer G, López-Otín C, Xiao J. Exercise sustains the hallmarks of health. JOURNAL OF SPORT AND HEALTH SCIENCE 2023; 12:8-35. [PMID: 36374766 PMCID: PMC9923435 DOI: 10.1016/j.jshs.2022.10.003] [Citation(s) in RCA: 34] [Impact Index Per Article: 34.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/17/2022] [Revised: 08/10/2022] [Accepted: 09/02/2022] [Indexed: 05/23/2023]
Abstract
Exercise has long been known for its active role in improving physical fitness and sustaining health. Regular moderate-intensity exercise improves all aspects of human health and is widely accepted as a preventative and therapeutic strategy for various diseases. It is well-documented that exercise maintains and restores homeostasis at the organismal, tissue, cellular, and molecular levels to stimulate positive physiological adaptations that consequently protect against various pathological conditions. Here we mainly summarize how moderate-intensity exercise affects the major hallmarks of health, including the integrity of barriers, containment of local perturbations, recycling and turnover, integration of circuitries, rhythmic oscillations, homeostatic resilience, hormetic regulation, as well as repair and regeneration. Furthermore, we summarize the current understanding of the mechanisms responsible for beneficial adaptations in response to exercise. This review aimed at providing a comprehensive summary of the vital biological mechanisms through which moderate-intensity exercise maintains health and opens a window for its application in other health interventions. We hope that continuing investigation in this field will further increase our understanding of the processes involved in the positive role of moderate-intensity exercise and thus get us closer to the identification of new therapeutics that improve quality of life.
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Affiliation(s)
- Yan Qiu
- Institute of Geriatrics (Shanghai University), Affiliated Nantong Hospital of Shanghai University (The Sixth People's Hospital of Nantong), School of Medicine, Shanghai University, Nantong 226011, China; Cardiac Regeneration and Ageing Lab, Institute of Cardiovascular Sciences, Shanghai Engineering Research Center of Organ Repair, School of Life Science, Shanghai University, Shanghai 200444, China
| | - Benjamin Fernández-García
- Health Research Institute of the Principality of Asturias (ISPA), Oviedo 33011, Spain; Department of Morphology and Cell Biology, Anatomy, University of Oviedo, Oviedo 33006, Spain
| | - H Immo Lehmann
- Cardiovascular Division of the Massachusetts General Hospital and Harvard Medical School, Boston, MA 02114, USA
| | - Guoping Li
- Cardiovascular Division of the Massachusetts General Hospital and Harvard Medical School, Boston, MA 02114, USA
| | - Guido Kroemer
- Centre de Recherche des Cordeliers, Equipe labellisée par la Ligue contre le cancer, Université de Paris Cité, Sorbonne Université, Inserm U1138, Institut Universitaire de France, Paris 75231, France; Metabolomics and Cell Biology Platforms, Institut Gustave Roussy, Villejuif 94805, France; Institut du Cancer Paris CARPEM, Department of Biology, Hôpital Européen Georges Pompidou, AP-HP, Paris 75015, France.
| | - Carlos López-Otín
- Departamento de Bioquímica y Biología Molecular, Facultad de Medicina, Instituto Universitario de Oncología, Universidad de Oviedo, Oviedo 33006, Spain; Centro de Investigación Biomédica en Red Enfermedades Cáncer (CIBERONC), Oviedo 33006, Spain.
| | - Junjie Xiao
- Institute of Geriatrics (Shanghai University), Affiliated Nantong Hospital of Shanghai University (The Sixth People's Hospital of Nantong), School of Medicine, Shanghai University, Nantong 226011, China; Cardiac Regeneration and Ageing Lab, Institute of Cardiovascular Sciences, Shanghai Engineering Research Center of Organ Repair, School of Life Science, Shanghai University, Shanghai 200444, China.
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Acute heat stress-indued apoptosis in mouse skeletal muscle is not associated with alteration of glutamine homeostasis. PLoS One 2022; 17:e0278176. [PMID: 36441734 PMCID: PMC9704566 DOI: 10.1371/journal.pone.0278176] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2022] [Accepted: 11/10/2022] [Indexed: 11/30/2022] Open
Abstract
We previously demonstrated that exposing mice to heat causes functional and ultrastructural mitochondrial alterations and apoptosis in skeletal muscle. Emerging evidence indicates that glutamine (Gln) deprivation may increase cell susceptibility to apoptosis whereas Gln supplementation may protect cells against heat stress. In this study, we investigated the effect of short-term Gln treatment on heat-induced changes in mouse skeletal muscle. Male mice received vehicle, low-dose Gln (100 mg/kg/d) or high-dose Gln (300 mg/kg/d) through daily gavage for 10 days before a heat exposure test. During heat exposure, mice displayed a hyperthermic response and no significant differences in peak core body temperature were noted across the three groups. Neither heat exposure nor pretreatment with low-dose or high-dose Gln significantly affected Gln concentrations in plasma and gastrocnemius muscles. Heat-exposed mice had significantly higher caspase 3/7 levels in gastrocnemius muscle compared to unexposed controls. Heat exposure significantly increased ROS production and mitochondrial fragmentation and decreased mitochondrial membrane potential in flexor digitorum brevis muscle. These changes were not affected by low- or high-dose Gln pretreatment. Together, acute heat stress did not disrupt Gln homeostasis in mouse skeletal muscle and Gln supplementation did not protect mouse skeletal muscle against heat-induced injury. The results of this study do not support a role of Gln in heat-induced skeletal muscle apoptosis.
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The effect of rugby training on indirect markers of gut permeability and gut damage in academy level rugby players. Eur J Appl Physiol 2022; 122:2545-2554. [PMID: 36053363 PMCID: PMC9613545 DOI: 10.1007/s00421-022-05027-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2022] [Accepted: 08/17/2022] [Indexed: 11/28/2022]
Abstract
Purpose To assess indirect markers of intestinal endothelial cell damage and permeability in academy rugby players in response to rugby training at the beginning and end of preseason. Methods Blood and urinary measures (intestinal fatty acid binding protein and lactulose:rhamnose) as measures of gastrointestinal cell damage and permeability were taken at rest and after a standardised collision-based rugby training session in 19 elite male academy rugby players (age: 20 ± 1 years, backs: 89.3 ± 8.4 kg; forwards: 111.8 ± 7.6 kg) at the start of preseason. A subsample (n = 5) repeated the protocol after six weeks of preseason training. Gastrointestinal symptoms (GIS; range of thirteen standard symptoms), aerobic capacity (30–15 intermittent fitness test), and strength (1 repetition maximum) were also measured. Results Following the rugby training session at the start of preseason, there was an increase (median; interquartile range) in intestinal fatty acid binding protein (2140; 1260–2730 to 3245; 1985–5143 pg/ml, p = 0.003) and lactulose:rhamnose (0.31; 0.26–0.34 to 0.97; 0.82–1.07, p < 0.001). After six weeks of preseason training players physical qualities improved, and the same trends in blood and urinary measures were observed within the subsample. Overall, the frequency and severity of GIS were low and not correlated to markers of endothelial damage. Conclusions Rugby training resulted in increased intestinal endothelial cell damage and permeability compared to rest. A similar magnitude of effect was observed after six weeks of pre-season training. This was not related to the experience of GIS.
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Assessment of Exercise-Associated Gastrointestinal Perturbations in Research and Practical Settings: Methodological Concerns and Recommendations for Best Practice. Int J Sport Nutr Exerc Metab 2022; 32:387-418. [PMID: 35963615 DOI: 10.1123/ijsnem.2022-0048] [Citation(s) in RCA: 18] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2022] [Revised: 05/26/2022] [Accepted: 07/07/2022] [Indexed: 12/14/2022]
Abstract
Strenuous exercise is synonymous with disturbing gastrointestinal integrity and function, subsequently prompting systemic immune responses and exercise-associated gastrointestinal symptoms, a condition established as "exercise-induced gastrointestinal syndrome." When exercise stress and aligned exacerbation factors (i.e., extrinsic and intrinsic) are of substantial magnitude, these exercise-associated gastrointestinal perturbations can cause performance decrements and health implications of clinical significance. This potentially explains the exponential growth in exploratory, mechanistic, and interventional research in exercise gastroenterology to understand, accurately measure and interpret, and prevent or attenuate the performance debilitating and health consequences of exercise-induced gastrointestinal syndrome. Considering the recent advancement in exercise gastroenterology research, it has been highlighted that published literature in the area is consistently affected by substantial experimental limitations that may affect the accuracy of translating study outcomes into practical application/s and/or design of future research. This perspective methodological review attempts to highlight these concerns and provides guidance to improve the validity, reliability, and robustness of the next generation of exercise gastroenterology research. These methodological concerns include participant screening and description, exertional and exertional heat stress load, dietary control, hydration status, food and fluid provisions, circadian variation, biological sex differences, comprehensive assessment of established markers of exercise-induced gastrointestinal syndrome, validity of gastrointestinal symptoms assessment tool, and data reporting and presentation. Standardized experimental procedures are needed for the accurate interpretation of research findings, avoiding misinterpreted (e.g., pathological relevance of response magnitude) and overstated conclusions (e.g., clinical and practical relevance of intervention research outcomes), which will support more accurate translation into safe practice guidelines.
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Chantler S, Griffiths A, Matu J, Davison G, Holliday A, Jones B. A systematic review: Role of dietary supplements on markers of exercise-associated gut damage and permeability. PLoS One 2022; 17:e0266379. [PMID: 35417467 PMCID: PMC9007357 DOI: 10.1371/journal.pone.0266379] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2021] [Accepted: 03/19/2022] [Indexed: 12/12/2022] Open
Abstract
Nutrition strategies and supplements may have a role to play in diminishing exercise associated gastrointestinal cell damage and permeability. The aim of this systematic review was to determine the influence of dietary supplements on markers of exercise-induced gut endothelial cell damage and/or permeability. Five databases were searched through to February 2021. Studies were selected that evaluated indirect markers of gut endothelial cell damage and permeability in response to exercise with and without a specified supplement, including with and without water. Acute and chronic supplementation protocols were included. Twenty-seven studies were included. The studies investigated a wide range of supplements including bovine colostrum, glutamine, probiotics, supplemental carbohydrate and protein, nitrate or nitrate precursors and water across a variety of endurance exercise protocols. The majority of studies using bovine colostrum and glutamine demonstrated a reduction in selected markers of gut cell damage and permeability compared to placebo conditions. Carbohydrate intake before and during exercise and maintaining euhydration may partially mitigate gut damage and permeability but coincide with other performance nutrition strategies. Single strain probiotic strains showed some positive findings, but the results are likely strain, dosage and duration specific. Bovine colostrum, glutamine, carbohydrate supplementation and maintaining euhydration may reduce exercise-associated endothelial damage and improve gut permeability. In spite of a large heterogeneity across the selected studies, appropriate inclusion of different nutrition strategies could mitigate the initial phases of gastrointestinal cell disturbances in athletes associated with exercise. However, research is needed to clarify if this will contribute to improved athlete gastrointestinal and performance outcomes.
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Affiliation(s)
- Sarah Chantler
- Carnegie Applied Rugby Research (CARR) Centre, Carnegie School of Sport, Leeds Beckett University, Leeds, United Kingdom
- Yorkshire Carnegie Rugby Union Club, Leeds, United Kingdom
| | - Alex Griffiths
- School of Clinical and Applied Sciences, Leeds Beckett University, Leeds, United Kingdom
| | - Jamie Matu
- School of Clinical and Applied Sciences, Leeds Beckett University, Leeds, United Kingdom
| | - Glen Davison
- Endurance Research Group, School of Sport and Exercise Sciences, University of Kent, Canterbury, United Kingdom
| | - Adrian Holliday
- Carnegie Applied Rugby Research (CARR) Centre, Carnegie School of Sport, Leeds Beckett University, Leeds, United Kingdom
- Human Nutrition Research Centre, Population Health Sciences Institute, Newcastle University, Newcastle upon Tyne, United Kingdom
| | - Ben Jones
- Carnegie Applied Rugby Research (CARR) Centre, Carnegie School of Sport, Leeds Beckett University, Leeds, United Kingdom
- School of Science and Technology, University of New England, Armidale, NSW, Australia
- Division of Exercise Science and Sports Medicine, Department of Human Biology, Faculty of Health Sciences, the University of Cape Town and the Sports Science Institute of South Africa, Cape Town, South Africa
- Leeds Rhinos Rugby League Club, Leeds, United Kingdom
- England Performance Unit, Rugby Football League, Leeds, United Kingdom
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13
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Tataka Y, Haramura M, Hamada Y, Ono M, Toyoda S, Yamada T, Hiratsu A, Suzuki K, Miyashita M. Effects of oral cystine and glutamine on exercise-induced changes in gastrointestinal permeability and damage markers in young men. Eur J Nutr 2022; 61:2331-2339. [PMID: 35106632 PMCID: PMC9279189 DOI: 10.1007/s00394-022-02806-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2021] [Accepted: 01/11/2022] [Indexed: 11/29/2022]
Abstract
PURPOSE Although acute prolonged strenuous exercise has been shown to increase markers of gastrointestinal permeability and damage, little is known regarding the efficacy of nutritional supplement interventions on the attenuation of exercise-induced gastrointestinal syndrome. This study addressed the effects of oral amino acid supplementation on markers of gastrointestinal permeability and damage in response to exercise. METHODS Sixteen active men aged 22.7 ± 2.6 years (mean ± standard deviation) completed placebo or cystine and glutamine supplementation trials in random order. Participants received either a placebo or cystine and glutamine supplements, three times a day for 5 days, separated by a 2-week washout period. On day 6, participants took their designated supplements 30 min before running at a speed corresponding to 75% of maximal oxygen uptake for 1 h, followed by a 4-h rest period. Blood samples were collected pre-exercise, immediately post-exercise, 30 min post-exercise, and 1, 2 and 4 h post-exercise on day 6. The plasma lactulose to mannitol ratio (L:M) and plasma intestinal fatty acid-binding protein (I-FABP) were used as markers of gastrointestinal permeability and damage, respectively. RESULTS Plasma L:M (linear mixed model, coefficient ± standard error: - 0.011 ± 0.004, P = 0.0090) and changes (i.e., from pre-exercise) in plasma I-FABP (linear mixed model, - 195.3 ± 65.7 coefficient ± standard error (pg/mL), P = 0.0035) were lower in the cystine and glutamine supplementation trial than in the placebo trial. CONCLUSION Oral cystine and glutamine supplementation attenuated the markers of gastrointestinal permeability and damage after 1 h of strenuous running in young men. TRIAL REGISTRATION NUMBER UMIN000026008. DATE OF REGISTRATION 13 December 2018.
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Affiliation(s)
- Yusei Tataka
- Graduate School of Sport Sciences, Waseda University, Saitama, Japan
| | - Miki Haramura
- Waseda Institute for Sport Sciences, Waseda University, Saitama, Japan
| | - Yuka Hamada
- Waseda Institute for Sport Sciences, Waseda University, Saitama, Japan
| | - Miho Ono
- Institute of Food Sciences and Technologies, Ajinomoto Co., Inc., Kanagawa, Japan
| | - Sakiko Toyoda
- Research Institute for Bioscience Products & Fine Chemicals, Ajinomoto Co., Inc., Kanagawa, Japan
| | | | - Ayano Hiratsu
- Graduate School of Sport Sciences, Waseda University, Saitama, Japan
| | - Katsuhiko Suzuki
- Faculty of Sport Sciences, Waseda University, 2-579-15 Mikajima, Tokorozawa, Saitama, 359-1192, Japan
| | - Masashi Miyashita
- Faculty of Sport Sciences, Waseda University, 2-579-15 Mikajima, Tokorozawa, Saitama, 359-1192, Japan.
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14
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Ogden HB, Fallowfield JL, Child RB, Davison G, Fleming SC, Delves SK, Millyard A, Westwood CS, Layden JD. No protective benefits of low dose acute L-glutamine supplementation on small intestinal permeability, epithelial injury and bacterial translocation biomarkers in response to subclinical exertional-heat stress: A randomized cross-over trial. Temperature (Austin) 2022; 9:196-210. [PMID: 36106146 PMCID: PMC9467553 DOI: 10.1080/23328940.2021.2015227] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
Exertional heat stress disrupts gastrointestinal permeability and, through subsequent bacterial translocation, can result in potentially fatal exertional heat stroke. Glutamine supplementation is a potential countermeasure although previously validated doses are not universally well tolerated. Ten males completed two 80-minute subclinical exertional heat stress tests (EHSTs) following either glutamine (0.3 g kg FFM-1) or placebo supplementation. Small intestinal permeability was assessed using the lactulose/rhamnose dual sugar absorption test and small intestinal epithelial injury using Intestinal Fatty-Acid Binding Protein (I-FABP). Bacterial translocation was assessed using the total 16S bacterial DNA and Bacteroides/total 16S DNA ratio. The glutamine bolus was well tolerated, with no participants reporting symptoms of gastrointestinal intolerance. Small intestinal permeability was not influenced by glutamine supplementation (p = 0.06) although a medium effect size favoring the placebo trial was observed (d = 0.73). Both small intestinal epithelial injury (p < 0.01) and Bacteroides/total 16S DNA (p = 0.04) increased following exertional heat stress, but were uninfluenced by glutamine supplementation. Low-dose acute oral glutamine supplementation does not protect gastrointestinal injury, permeability, or bacterial translocation in response to subclinical exertional heat stress.
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Affiliation(s)
- Henry B. Ogden
- School of Sport, Health and Wellbeing, Plymouth MARJON University, Plymouth, UK,CONTACT Henry B. Ogden
| | - Joanne L. Fallowfield
- Environmental Medicine and Science Division, Institute of Naval Medicine, Alverstoke, UK
| | - Robert B. Child
- School of Chemical Engineering, University of Birmingham, Birmingham, UK
| | - Glen Davison
- Endurance Research Group, School of Sport and Exercise Sciences, University of Kent, Chatham Maritime, UK
| | - Simon C. Fleming
- Department of Clinical Chemistry, Royal Cornwall NHS Trust, Truro, UK
| | - Simon K. Delves
- Environmental Medicine and Science Division, Institute of Naval Medicine, Alverstoke, UK
| | - Alison Millyard
- School of Sport, Health and Wellbeing, Plymouth MARJON University, Plymouth, UK
| | | | - Joseph D. Layden
- School of Sport, Health and Wellbeing, Plymouth MARJON University, Plymouth, UK
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15
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Wilson P. Sport supplements and the athlete's gut: a review. Int J Sports Med 2021; 43:840-849. [PMID: 34814219 DOI: 10.1055/a-1704-3086] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
Vigorous or prolonged exercise poses a challenge to gastrointestinal system functioning and is associated with digestive symptoms. This narrative review addresses 1) the potential of dietary supplements to enhance gut function and reduce exercise-associated gastrointestinal symptoms and 2) strategies for reducing gastrointestinal-related side effects resulting from popular sports supplements. Several supplements, including probiotics, glutamine, and bovine colostrum, have been shown to reduce markers of gastrointestinal damage and permeability with exercise. Yet, the clinical ramifications of these findings are uncertain, as improvements in symptoms have not been consistently observed. Among these supplements, probiotics modestly reduced exercise-associated gastrointestinal symptoms in a few studies, suggesting they are the most evidenced-based choice for athletes looking to manage such symptoms through supplementation. Carbohydrate, caffeine, and sodium bicarbonate are evidence-based supplements that can trigger gastrointestinal symptoms. Using glucose-fructose mixtures is beneficial when carbohydrate ingestion is high (>50 g/h) during exercise, and undertaking multiple gut training sessions prior to competition may also be helpful. Approaches for preventing caffeine-induced gastrointestinal disturbances include using low-to-moderate doses (<500 mg) and avoiding/minimizing exacerbating factors (stress, anxiety, other stimulants, fasting). Adverse gastrointestinal effects of sodium bicarbonate can be avoided by using enteric-coated formulations, low doses (0.2 g/kg), or multi-day loading protocols.
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Affiliation(s)
- Patrick Wilson
- Human Movement Sciences, Old Dominion University, Norfolk, United States
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16
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Ogden HB, Fallowfield JL, Child RB, Davison G, Fleming SC, Delves SK, Millyard A, Westwood CS, Layden JD. Acute L-Glutamine Supplementation does not improve Gastrointestinal Permeability, Injury or Microbial Translocation in Response to Exhaustive High Intensity Exertional-Heat Stress. Eur J Sport Sci 2021; 22:1865-1876. [PMID: 34726114 DOI: 10.1080/17461391.2021.2001575] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
PurposeExertional-heat stress adversely distrupts (GI) barrier integrity and, through subsequent microbial translocation (MT), can result in potentially fatal exertional-heat stroke. Acute glutamine (GLN) supplementation is a potential nutritional countermeasure, although the practical value of current supplementation regimens is questionable. Method: Ten males completed two high-intensity exertional-heat stress tests (EHST) involving running in the heat (40°C and 40% relative humidity) at lactate threshold to volitional exhaustion. Participants ingested GLN (0.3 g·kg·FFM-1) or a non-calorific placebo (PLA) one hour prior to the EHST. Venous blood was drawn pre-, post- and one-hour post-EHST. GI permeability was assessed using a serum dual-sugar absorption test (DSAT) and small intestinal epithelial injury using plasma Intestinal Fatty-Acid Binding Protein (I-FABP). MT was assessed using the Bacteroides/total 16S DNA ratio. Results: Volitional exhaustion occurred after 22:19 ± 2:22 (minutes: seconds) in both conditions, during which whole-body physiological responses and GI symptoms were not different (p ˃ 0.05). GI permeability (serum DSAT) was greater following GLN (0.043 ± 0.020) than PLA (0.034 ± 0.019) (p = 0.02; d = 0.47), but small intestine epithelial injury (I-FABP) increased comparably (p = 0.22; η2p = 0.16) following the EHST in both trials (GLN Δ = 1.25 ± 0.63 ng·ml-1; PLA Δ= 0.92 ± 0.44 ng·ml-1). GI MT (Bacteroides/total 16S DNA ratio) was unchanged in either condition following the EHST (p = 0.43). Conclusion: Acute low-dose (0.3 g·kg-1 fat free mass) GLN supplementation ingested one hour before high-intesity exertional-heat stress worsened GI permeability, but did not influence either small intestinal epithilial injury or microbial translocation.Highlights: The pathophysiology of exertional-heat stroke is widely hypothesised to be at least in part attributable to a systemic inflammatory response caused by the leak of gastrointestinal microbes into the circulating blood.Acute high-dose (0.9 g·kg·FFM-1) L-glutamine supplementation is widely promoted as a practical strategy to protect gastrointestinal barrier integrity during exertional-heat stress. However, previously validated doses are often poorly tolerated and cannot be recommended for widespread implementation.This study examined the efficacy of low-dose (0.30 g·kg·FFM-1; ∼20 grams) acute L-glutamine supplementation on small intestinal injury, permeability, and microbial translocation in response a high-intensity exertional-heat stress test to exhaustion (20 - 30 minutes). This type of exercise accounts for the majority of exertional-heat stroke cases in the military.Despite being universally well-tolerated across all participants, acute low-dose L-glutamine supplementation worsened gastrointestinal permeability, without influencing either small intestinal injury or microbial translocation. These findings do not support the application of low-dose L-glutamine supplementation to help prevent exertional-heat stroke.
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Affiliation(s)
- Henry B Ogden
- School of Sport, Health and Wellbeing, Plymouth MARJON University, Plymouth, United Kingdom
| | | | - Robert B Child
- School of Chemical Engineering, University of Birmingham, Birmingham, United Kingdom
| | - Glen Davison
- Endurance Research Group, School of Sport and Exercise Sciences, University of Kent, Chatham Maritime, United Kingdom
| | | | | | - Alison Millyard
- School of Sport, Health and Wellbeing, Plymouth MARJON University, Plymouth, United Kingdom
| | - Caroline S Westwood
- School of Sport, Health and Wellbeing, Plymouth MARJON University, Plymouth, United Kingdom
| | - Joseph D Layden
- School of Sport, Health and Wellbeing, Plymouth MARJON University, Plymouth, United Kingdom
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17
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Walter E, W Watt P, Gibson OR, Wilmott AGB, Mitchell D, Moreton R, Maxwell NS. Exercise hyperthermia induces greater changes in gastrointestinal permeability than equivalent passive hyperthermia. Physiol Rep 2021; 9:e14945. [PMID: 34409760 PMCID: PMC8374382 DOI: 10.14814/phy2.14945] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2021] [Revised: 06/05/2021] [Accepted: 06/06/2021] [Indexed: 01/09/2023] Open
Abstract
Hyperthermia and exertional heat illness increase gastrointestinal (GI) permeability, although whether the latter is only via hyperthermia is unclear. The aim of this pilot study was to determine whether different changes in GI permeability, characterized by an increased plasma lactulose:rhamnose concentration ratio ([L:R]), occurred in exercise hyperthermia in comparison to equivalent passive hyperthermia. Six healthy adult male participants (age 25 ± 5 years, mass 77.0 ± 6.7 kg, height 181 ± 6 cm, peak oxygen uptake [ V · O 2 peak ] 48 ± 8 ml.kg-1 .min-1 ) underwent exercise under hot conditions (Ex-Heat) and passive heating during hot water immersion (HWI). Heart rate (HR), rectal temperature (TCORE ), rating of perceived exertion (RPE), and whole-body sweat loss (WBSL) were recorded throughout the trials. The L:R ratio, peak HR, change in HR, and change in RPE were higher in Ex-Heat than HWI, despite no differences in trial duration, peak core temperature or WBSL. L:R was strongly correlated (p < 0.05) with HR peak (r = 0.626) and change in HR (r = 0.615) but no other variable. The greater L:R in Ex-Heat, despite equal TCORE responses to HWI, indicates that increased cardiovascular strain occurred during exercise, and exacerbates hyperthermia-induced GI permeability at the same absolute temperature.
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Affiliation(s)
- Edward Walter
- Department of Intensive CareRoyal Surrey County HospitalGuildfordUK
- Environmental Extremes Lab, Sport and Exercise Science and Medicine Research and Enterprise GroupUniversity of BrightonEastbourneEast SussexUK
| | - Peter W Watt
- Environmental Extremes Lab, Sport and Exercise Science and Medicine Research and Enterprise GroupUniversity of BrightonEastbourneEast SussexUK
| | - Oliver R. Gibson
- Centre for Human Performance, Exercise and Rehabilitation (CHPER)Division of Sport, Health and Exercise SciencesCollege of Health, Medicine, and Life SciencesBrunel University LondonUxbridgeUK
| | - Ashley G. B. Wilmott
- Environmental Extremes Lab, Sport and Exercise Science and Medicine Research and Enterprise GroupUniversity of BrightonEastbourneEast SussexUK
- Cambridge Centre for Sport and Exercise Sciences (CCSES)School of Psychology and Sport ScienceAnglia Ruskin UniversityCambridgeUK
| | - Dominic Mitchell
- Environmental Extremes Lab, Sport and Exercise Science and Medicine Research and Enterprise GroupUniversity of BrightonEastbourneEast SussexUK
| | - Robert Moreton
- Environmental Extremes Lab, Sport and Exercise Science and Medicine Research and Enterprise GroupUniversity of BrightonEastbourneEast SussexUK
| | - Neil S. Maxwell
- Environmental Extremes Lab, Sport and Exercise Science and Medicine Research and Enterprise GroupUniversity of BrightonEastbourneEast SussexUK
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18
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Hydrogel Carbohydrate-Electrolyte Beverage Does Not Improve Glucose Availability, Substrate Oxidation, Gastrointestinal Symptoms or Exercise Performance, Compared With a Concentration and Nutrient-Matched Placebo. Int J Sport Nutr Exerc Metab 2021; 30:25-33. [PMID: 31629348 DOI: 10.1123/ijsnem.2019-0090] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2019] [Revised: 06/04/2019] [Accepted: 07/01/2019] [Indexed: 11/18/2022]
Abstract
The impact of a carbohydrate-electrolyte solution with sodium alginate and pectin for hydrogel formation (CES-HGel), was compared to a standard CES with otherwise matched ingredients (CES-Std), for blood glucose, substrate oxidation, gastrointestinal symptoms (GIS; nausea, belching, bloating, pain, regurgitation, flatulence, urge to defecate, and diarrhea), and exercise performance. Nine trained male endurance runners completed 3 hr of steady-state running (SS) at 60% V˙O2max, consuming 90 g/hr of carbohydrate from CES-HGel or CES-Std (53 g/hr maltodextrin, 37 g/hr fructose, 16% w/v solution) in a randomized crossover design, followed by an incremental time to exhaustion (TTE) test. Blood glucose and substrate oxidation were measured every 30 min during SS and oxidation throughout TTE. Breath hydrogen (H2) was measured every 30 min during exercise and every 15 min for 2 hr postexercise. GIS were recorded every 15 min throughout SS, immediately after and every 15-min post-TTE. No differences in blood glucose (incremental area under the curve [mean ± SD]: CES-HGel 1,100 ± 96 mmol·L-1·150 min-1 and CES-Std 1,076 ± 58 mmol·L-1·150 min-1; p = .266) were observed during SS. There were no differences in substrate oxidation during SS (carbohydrate: p = .650; fat: p = .765) or TTE (carbohydrate: p = .466; fat: p = .633) and no effect of trial on GIS incidence (100% in both trials) or severity (summative rating score: CES-HGel 29.1 ± 32.6 and CES-Std 34.8 ± 34.8; p = .262). Breath hydrogen was not different between trials (p = .347), nor was TTE performance (CES-HGel 722 ± 182 s and CES-Std: 756 ± 187 s; p = .08). In conclusion, sodium alginate and pectin added to a CES consumed during endurance running does not alter the blood glucose responses, carbohydrate malabsorption, substrate oxidation, GIS, or TTE beyond those of a CES with otherwise matched ingredients.
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19
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Smith KA, Pugh JN, Duca FA, Close GL, Ormsbee MJ. Gastrointestinal pathophysiology during endurance exercise: endocrine, microbiome, and nutritional influences. Eur J Appl Physiol 2021; 121:2657-2674. [PMID: 34131799 DOI: 10.1007/s00421-021-04737-x] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2021] [Accepted: 06/07/2021] [Indexed: 12/17/2022]
Abstract
Gastrointestinal symptoms are abundant among athletes engaging in endurance exercise, particularly when exercising in increased environmental temperatures, at higher intensities, or over extremely long distances. It is currently thought that prolonged ischemia, mechanical damage to the epithelial lining, and loss of epithelial barrier integrity are likely contributors of gastrointestinal (GI) distress during bouts of endurance exercise, but due to the many potential causes and sporadic nature of symptoms this phenomenon has proven difficult to study. In this review, we cover known factors that contribute to GI distress symptoms in athletes during exercise, while further attempting to identify novel avenues of future research to help elucidate mechanisms leading to symptomology. We explore the link between the intestinal microbiome, the integrity of the gut epithelia, and add detail on gut hormone and peptide secretion that could potentially contribute to GI distress symptoms in athletes. The influence of nutrition and dietary supplementation strategies are also detailed, where much research has opened up new ideas and potential mechanisms for understanding gut pathophysiology during exercise. The etiology of gastrointestinal symptoms during endurance exercise is multi-factorial with neuroendocrine, microbial, and nutritional factors likely contributing to specific, individualized symptoms. Recent work in previously unexplored areas of both microbiome and gut peptide secretion are pertinent areas for future work, and the numerous supplementation strategies explored to date have provided insight into physiological mechanisms that may be targetable to reduce the incidence and severity of gastrointestinal symptoms in athletes.
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Affiliation(s)
- Kyle A Smith
- Department of Nutritional Sciences, University of Arizona, Tucson, AZ, USA
| | - Jamie N Pugh
- Research Institute for Sport and Exercise Sciences, Liverpool John Moores University, Liverpool, L3 5UA, UK
| | - Frank A Duca
- School of Animal and Comparative Biomedical Sciences, University of Arizona, Tucson, AZ, USA
| | - Graeme L Close
- Research Institute for Sport and Exercise Sciences, Liverpool John Moores University, Liverpool, L3 5UA, UK
| | - Michael J Ormsbee
- Department of Nutrition and Integrative Physiology, Institute of Sports Sciences and Medicine, Florida State University, 1104 Spirit Way, Tallahassee, FL, 32306, USA. .,Discipline of Biokinetics, Exercise and Leisure Sciences, University of KwaZulu-Natal, Durban, 4041, South Africa.
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20
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King MA, Rollo I, Baker LB. Nutritional considerations to counteract gastrointestinal permeability during exertional heat stress. J Appl Physiol (1985) 2021; 130:1754-1765. [PMID: 33955260 DOI: 10.1152/japplphysiol.00072.2021] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Intestinal barrier integrity and function are compromised during exertional heat stress (EHS) potentially leading to consequences that range from minor gastrointestinal (GI) disturbances to fatal outcomes in exertional heat stroke or septic shock. This mini-review provides a concise discussion of nutritional interventions that may protect against intestinal permeability during EHS and suggests physiological mechanisms responsible for this protection. Although diverse nutritional interventions have been suggested to be protective against EHS-induced GI permeability, the ingestion of certain amino acids, carbohydrates, and fluid per se is potentially effective strategy, whereas evidence for various polyphenols and pre/probiotics is developing. Plausible physiological mechanisms of protection include increased blood flow, epithelial cell proliferation, upregulation of intracellular heat shock proteins, modulation of inflammatory signaling, alteration of the GI microbiota, and increased expression of tight junction (TJ) proteins. Further clinical research is needed to propose specific nutritional candidates and recommendations for their application to prevent intestinal barrier disruption and elucidate mechanisms during EHS.
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Affiliation(s)
- Michelle A King
- Gatorade Sports Science Institute, PepsiCo R&D Life Sciences, Barrington, Illinois
| | - Ian Rollo
- Gatorade Sports Science Institute, PepsiCo R&D Life Sciences, Leicestershire, United Kingdom
| | - Lindsay B Baker
- Gatorade Sports Science Institute, PepsiCo R&D Life Sciences, Barrington, Illinois
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21
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Chantler S, Griffiths A, Matu J, Davison G, Jones B, Deighton K. The Effects of Exercise on Indirect Markers of Gut Damage and Permeability: A Systematic Review and Meta-analysis. Sports Med 2021; 51:113-124. [PMID: 33201454 PMCID: PMC7806566 DOI: 10.1007/s40279-020-01348-y] [Citation(s) in RCA: 37] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
AIM Exercise appears to cause damage to the endothelial lining of the human gastrointestinal tract and elicit a significant increase in gut permeability. OBJECTIVE The aim of this review was to determine the effect of an acute bout of exercise on gut damage and permeability outcomes in healthy populations using a meta-analysis. METHODS PubMed, The Cochrane Library as well as MEDLINE, SPORTDiscus and CINHAL, via EBSCOhost were searched through February 2019. Studies were selected that evaluated urinary (ratio of disaccharide/monosaccharide excretion) or plasma markers [intestinal Fatty Acid Binding Protein (i-FABP)] of gut permeability and gut cell damage in response to a single bout of exercise. RESULTS A total of 34 studies were included. A random-effects meta-analysis was performed, and showed a large and moderate effect size for markers of gut damage (i-FABP) (ES 0.81; 95% CI 0.63-0.98; n = 26; p < 0.001) and gut permeability (Disaccharide Sugar/Monosaccharide Sugar) (ES 0.70; 95% CI 0.29-1.11; n = 17; p < 0.001), respectively. Exercise performed in hot conditions (> 23 °C) further increased markers of gut damage compared with thermoneutral conditions [ES 1.06 (95% CI 0.88-1.23) vs. 0.66 (95% CI 0.43-0.89); p < 0.001]. Exercise duration did not have any significant effect on gut damage or permeability outcomes. CONCLUSIONS These findings demonstrate that a single bout of exercise increases gut damage and gut permeability in healthy participants, with gut damage being exacerbated in hot environments. Further investigation into nutritional strategies to minimise gut damage and permeability after exercise is required. PROSPERO database number (CRD42018086339).
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Affiliation(s)
- Sarah Chantler
- Carnegie Applied Rugby Research (CARR) Centre, Institute for Sport, Physical Activity and Leisure, Leeds Beckett University, Cavendish G08, Headingley Campus, Leeds, LS6 3QT, UK.
- Yorkshire Carnegie Rugby Union Club, Leeds, UK.
| | - Alex Griffiths
- Carnegie Applied Rugby Research (CARR) Centre, Institute for Sport, Physical Activity and Leisure, Leeds Beckett University, Cavendish G08, Headingley Campus, Leeds, LS6 3QT, UK
| | - Jamie Matu
- School of Clinical and Applied Sciences, Leeds Beckett University, Leeds, UK
| | - Glen Davison
- Endurance Research Group, School of Sport and Exercise Sciences, University of Kent, Canterbury, UK
| | - Ben Jones
- Carnegie Applied Rugby Research (CARR) Centre, Institute for Sport, Physical Activity and Leisure, Leeds Beckett University, Cavendish G08, Headingley Campus, Leeds, LS6 3QT, UK
- School of Science and Technology, University of New England, Armidale, NSW, Australia
- Division of Exercise Science and Sports Medicine, Department of Human Biology, Faculty of Health Sciences, The University of Cape Town and the Sports Science Institute of South Africa, Cape Town, South Africa
- Leeds Rhinos Rugby League Club, Leeds, UK
- England Performance Unit, Rugby Football League, Leeds, UK
| | - Kevin Deighton
- Carnegie Applied Rugby Research (CARR) Centre, Institute for Sport, Physical Activity and Leisure, Leeds Beckett University, Cavendish G08, Headingley Campus, Leeds, LS6 3QT, UK
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22
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Ogden HB, Child RB, Fallowfield JL, Delves SK, Westwood CS, Millyard A, Layden JD. Gastrointestinal Tolerance of Low, Medium and High Dose Acute Oral l-Glutamine Supplementation in Healthy Adults: A Pilot Study. Nutrients 2020; 12:nu12102953. [PMID: 32992440 PMCID: PMC7601811 DOI: 10.3390/nu12102953] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2020] [Revised: 09/09/2020] [Accepted: 09/18/2020] [Indexed: 12/14/2022] Open
Abstract
l-Glutamine (GLN) is a conditionally essential amino acid which supports gastrointestinal (GI) and immune function prior to catabolic stress (e.g., strenuous exercise). Despite potential dose-dependent benefits, GI tolerance of acute high dose oral GLN supplementation is poorly characterised. Fourteen healthy males (25 ± 5 years; 1.79 ± 0.07 cm; 77.7 ± 9.8 kg; 14.8 ± 4.6% body fat) ingested 0.3 (LOW), 0.6 (MED) or 0.9 (HIGH) g·kg·FFM−1 GLN beverages, in a randomised, double-blind, counter-balanced, cross-over trial. Individual and accumulated GI symptoms were recorded using a visual analogue scale at regular intervals up to 24-h post ingestion. GLN beverages were characterised by tonicity measurement and microscopic observations. 24-h accumulated upper- and lower- and total-GI symptoms were all greater in the HIGH, compared to LOW and MED trials (p < 0.05). Specific GI symptoms (discomfort, nausea, belching, upper GI pain) were all more pronounced on the HIGH versus LOW GLN trial (p < 0.05). Nevertheless, most symptoms were still rated as mild. In comparison, the remaining GI symptoms were either comparable (flatulence, urge to regurgitate, bloating, lower GI pain) or absent (heart burn, vomiting, urge to defecate, abnormal stools, stitch, dizziness) between trials (p > 0.05). All beverages were isotonic and contained a dose-dependent number of GLN crystals. Acute oral GLN ingestion in dosages up to 0.9 g·kg·FFM−1 are generally well-tolerated. However, the severity of mild GI symptoms appeared dose-dependent during the first two hours post prandial and may be due to high-concentrations of GLN crystals.
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Affiliation(s)
- Henry B. Ogden
- Faculty of Sport, Health and Wellbeing, Plymouth MARJON University, Plymouth PL6 8BH, UK; (C.S.W.); (A.M.); (J.D.L.)
- Correspondence:
| | - Robert B. Child
- School of Chemical Engineering, University of Birmingham, Birmingham B15 2TT, UK;
| | | | - Simon K. Delves
- Institute of Naval Medicine, Alverstoke PO12 2DL, UK; (J.L.F.); (S.K.D.)
| | - Caroline S. Westwood
- Faculty of Sport, Health and Wellbeing, Plymouth MARJON University, Plymouth PL6 8BH, UK; (C.S.W.); (A.M.); (J.D.L.)
| | - Alison Millyard
- Faculty of Sport, Health and Wellbeing, Plymouth MARJON University, Plymouth PL6 8BH, UK; (C.S.W.); (A.M.); (J.D.L.)
| | - Joseph D. Layden
- Faculty of Sport, Health and Wellbeing, Plymouth MARJON University, Plymouth PL6 8BH, UK; (C.S.W.); (A.M.); (J.D.L.)
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Pugh JN, Wagenmakers AJM, Doran DA, Fleming SC, Fielding BA, Morton JP, Close GL. Probiotic supplementation increases carbohydrate metabolism in trained male cyclists: a randomized, double-blind, placebo-controlled crossover trial. Am J Physiol Endocrinol Metab 2020; 318:E504-E513. [PMID: 32069071 DOI: 10.1152/ajpendo.00452.2019] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
We hypothesized that probiotic supplementation (PRO) increases the absorption and oxidation of orally ingested maltodextrin during 2 h endurance cycling, thereby sparing muscle glycogen for a subsequent time trial (simulating a road race). Measurements were made of lipid and carbohydrate oxidation, plasma metabolites and insulin, gastrointestinal (GI) permeability, and subjective symptoms of discomfort. Seven male cyclists were randomized to PRO (bacterial composition given in methods) or placebo for 4 wk, separated by a 14-day washout period. After each period, cyclists consumed a 10% maltodextrin solution (initial 8 mL/kg bolus and 2 mL/kg every 15 min) while exercising for 2 h at 55% maximal aerobic power output, followed by a 100-kJ time trial. PRO resulted in small increases in peak oxidation rates of the ingested maltodextrin (0.84 ± 0.10 vs. 0.77 ± 0.09 g/min; P = 0.016) and mean total carbohydrate oxidation (2.20 ± 0.25 vs. 1.87 ± 0.39 g/min; P = 0.038), whereas fat oxidation was reduced (0.40 ± 0.11 vs. 0.55 ± 0.10 g/min; P = 0.021). During PRO, small but significant increases were seen in glucose absorption, plasma glucose, and insulin concentration and decreases in nonesterified fatty acid and glycerol. Differences between markers of GI damage and permeability and time-trial performance were not significant (P > 0.05). In contrast to the hypothesis, PRO led to minimal increases in absorption and oxidation of the ingested maltodextrin and small reductions in fat oxidation, whereas having no effect on subsequent time-trial performance.
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Affiliation(s)
- Jamie N Pugh
- Research Institute for Sport and Exercise Sciences, Liverpool John Moores University, Liverpool, United Kingdom
| | - Anton J M Wagenmakers
- Research Institute for Sport and Exercise Sciences, Liverpool John Moores University, Liverpool, United Kingdom
| | - Dominic A Doran
- Research Institute for Sport and Exercise Sciences, Liverpool John Moores University, Liverpool, United Kingdom
| | | | - Barbara A Fielding
- Department of Nutritional Sciences, University of Surrey, Guildford, Surrey, United Kingdom
| | - James P Morton
- Research Institute for Sport and Exercise Sciences, Liverpool John Moores University, Liverpool, United Kingdom
| | - Graeme L Close
- Research Institute for Sport and Exercise Sciences, Liverpool John Moores University, Liverpool, United Kingdom
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Ogden HB, Child RB, Fallowfield JL, Delves SK, Westwood CS, Layden JD. The Gastrointestinal Exertional Heat Stroke Paradigm: Pathophysiology, Assessment, Severity, Aetiology and Nutritional Countermeasures. Nutrients 2020; 12:E537. [PMID: 32093001 PMCID: PMC7071449 DOI: 10.3390/nu12020537] [Citation(s) in RCA: 32] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2020] [Revised: 02/14/2020] [Accepted: 02/15/2020] [Indexed: 12/12/2022] Open
Abstract
Exertional heat stroke (EHS) is a life-threatening medical condition involving thermoregulatory failure and is the most severe condition along a continuum of heat-related illnesses. Current EHS policy guidance principally advocates a thermoregulatory management approach, despite growing recognition that gastrointestinal (GI) microbial translocation contributes to disease pathophysiology. Contemporary research has focused to understand the relevance of GI barrier integrity and strategies to maintain it during periods of exertional-heat stress. GI barrier integrity can be assessed non-invasively using a variety of in vivo techniques, including active inert mixed-weight molecular probe recovery tests and passive biomarkers indicative of GI structural integrity loss or microbial translocation. Strenuous exercise is strongly characterised to disrupt GI barrier integrity, and aspects of this response correlate with the corresponding magnitude of thermal strain. The aetiology of GI barrier integrity loss following exertional-heat stress is poorly understood, though may directly relate to localised hyperthermia, splanchnic hypoperfusion-mediated ischemic injury, and neuroendocrine-immune alterations. Nutritional countermeasures to maintain GI barrier integrity following exertional-heat stress provide a promising approach to mitigate EHS. The focus of this review is to evaluate: (1) the GI paradigm of exertional heat stroke; (2) techniques to assess GI barrier integrity; (3) typical GI barrier integrity responses to exertional-heat stress; (4) the aetiology of GI barrier integrity loss following exertional-heat stress; and (5) nutritional countermeasures to maintain GI barrier integrity in response to exertional-heat stress.
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Affiliation(s)
- Henry B. Ogden
- Faculty of Sport, Health and Wellbeing, Plymouth MARJON University, Derriford Rd, Plymouth PL6 8BH, UK; (C.S.W.); (J.D.L.)
| | - Robert B. Child
- School of Chemical Engineering, University of Birmingham, Birmingham B15 2QU, UK;
| | | | - Simon K. Delves
- Institute of Naval Medicine, Alverstoke PO12 2DW, UK; (J.L.F.); (S.K.D.)
| | - Caroline S. Westwood
- Faculty of Sport, Health and Wellbeing, Plymouth MARJON University, Derriford Rd, Plymouth PL6 8BH, UK; (C.S.W.); (J.D.L.)
| | - Joseph D. Layden
- Faculty of Sport, Health and Wellbeing, Plymouth MARJON University, Derriford Rd, Plymouth PL6 8BH, UK; (C.S.W.); (J.D.L.)
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25
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Parsons IT, Stacey MJ, Woods DR. Heat Adaptation in Military Personnel: Mitigating Risk, Maximizing Performance. Front Physiol 2019; 10:1485. [PMID: 31920694 PMCID: PMC6928107 DOI: 10.3389/fphys.2019.01485] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2019] [Accepted: 11/21/2019] [Indexed: 12/22/2022] Open
Abstract
The study of heat adaptation in military personnel offers generalizable insights into a variety of sporting, recreational and occupational populations. Conversely, certain characteristics of military employment have few parallels in civilian life, such as the imperative to achieve mission objectives during deployed operations, the opportunity to undergo training and selection for elite units or the requirement to fulfill essential duties under prolonged thermal stress. In such settings, achieving peak individual performance can be critical to organizational success. Short-notice deployment to a hot operational or training environment, exposure to high intensity exercise and undertaking ceremonial duties during extreme weather may challenge the ability to protect personnel from excessive thermal strain, especially where heat adaptation is incomplete. Graded and progressive acclimatization can reduce morbidity substantially and impact on mortality rates, yet individual variation in adaptation has the potential to undermine empirical approaches. Incapacity under heat stress can present the military with medical, occupational and logistic challenges requiring dynamic risk stratification during initial and subsequent heat stress. Using data from large studies of military personnel observing traditional and more contemporary acclimatization practices, this review article (1) characterizes the physical challenges that military training and deployed operations present (2) considers how heat adaptation has been used to augment military performance under thermal stress and (3) identifies potential solutions to optimize the risk-performance paradigm, including those with broader relevance to other populations exposed to heat stress.
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Affiliation(s)
- Iain T. Parsons
- Academic Department of Military Medicine, Research and Clinical Innovation, Royal Centre for Defence Medicine, Birmingham, United Kingdom
- School of Cardiovascular Medicine & Sciences, Faculty of Life Sciences & Medicine, King’s College London, London, United Kingdom
| | - Michael J. Stacey
- Academic Department of Military Medicine, Research and Clinical Innovation, Royal Centre for Defence Medicine, Birmingham, United Kingdom
- Department of Diabetes and Endocrinology, Imperial College Healthcare NHS Trust, London, United Kingdom
| | - David R. Woods
- Academic Department of Military Medicine, Research and Clinical Innovation, Royal Centre for Defence Medicine, Birmingham, United Kingdom
- Department of Sport and Exercise Endocrinology, Carnegie Research Institute, Leeds Beckett University, Leeds, United Kingdom
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26
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Torre-Villalvazo I, Alemán-Escondrillas G, Valle-Ríos R, Noriega LG. Protein intake and amino acid supplementation regulate exercise recovery and performance through the modulation of mTOR, AMPK, FGF21, and immunity. Nutr Res 2019; 72:1-17. [DOI: 10.1016/j.nutres.2019.06.006] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2019] [Revised: 05/16/2019] [Accepted: 06/26/2019] [Indexed: 12/12/2022]
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27
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Tiller NB, Roberts JD, Beasley L, Chapman S, Pinto JM, Smith L, Wiffin M, Russell M, Sparks SA, Duckworth L, O'Hara J, Sutton L, Antonio J, Willoughby DS, Tarpey MD, Smith-Ryan AE, Ormsbee MJ, Astorino TA, Kreider RB, McGinnis GR, Stout JR, Smith JW, Arent SM, Campbell BI, Bannock L. International Society of Sports Nutrition Position Stand: nutritional considerations for single-stage ultra-marathon training and racing. J Int Soc Sports Nutr 2019; 16:50. [PMID: 31699159 PMCID: PMC6839090 DOI: 10.1186/s12970-019-0312-9] [Citation(s) in RCA: 71] [Impact Index Per Article: 14.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2019] [Accepted: 09/24/2019] [Indexed: 12/12/2022] Open
Abstract
Background In this Position Statement, the International Society of Sports Nutrition (ISSN) provides an objective and critical review of the literature pertinent to nutritional considerations for training and racing in single-stage ultra-marathon. Recommendations for Training. i) Ultra-marathon runners should aim to meet the caloric demands of training by following an individualized and periodized strategy, comprising a varied, food-first approach; ii) Athletes should plan and implement their nutrition strategy with sufficient time to permit adaptations that enhance fat oxidative capacity; iii) The evidence overwhelmingly supports the inclusion of a moderate-to-high carbohydrate diet (i.e., ~ 60% of energy intake, 5–8 g·kg− 1·d− 1) to mitigate the negative effects of chronic, training-induced glycogen depletion; iv) Limiting carbohydrate intake before selected low-intensity sessions, and/or moderating daily carbohydrate intake, may enhance mitochondrial function and fat oxidative capacity. Nevertheless, this approach may compromise performance during high-intensity efforts; v) Protein intakes of ~ 1.6 g·kg− 1·d− 1 are necessary to maintain lean mass and support recovery from training, but amounts up to 2.5 g.kg− 1·d− 1 may be warranted during demanding training when calorie requirements are greater; Recommendations for Racing. vi) To attenuate caloric deficits, runners should aim to consume 150–400 Kcal·h− 1 (carbohydrate, 30–50 g·h− 1; protein, 5–10 g·h− 1) from a variety of calorie-dense foods. Consideration must be given to food palatability, individual tolerance, and the increased preference for savory foods in longer races; vii) Fluid volumes of 450–750 mL·h− 1 (~ 150–250 mL every 20 min) are recommended during racing. To minimize the likelihood of hyponatraemia, electrolytes (mainly sodium) may be needed in concentrations greater than that provided by most commercial products (i.e., > 575 mg·L− 1 sodium). Fluid and electrolyte requirements will be elevated when running in hot and/or humid conditions; viii) Evidence supports progressive gut-training and/or low-FODMAP diets (fermentable oligosaccharide, disaccharide, monosaccharide and polyol) to alleviate symptoms of gastrointestinal distress during racing; ix) The evidence in support of ketogenic diets and/or ketone esters to improve ultra-marathon performance is lacking, with further research warranted; x) Evidence supports the strategic use of caffeine to sustain performance in the latter stages of racing, particularly when sleep deprivation may compromise athlete safety.
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Affiliation(s)
- Nicholas B Tiller
- Division of Pulmonary and Critical Care Physiology and Medicine, The Lundquist Institute for Biomedical Innovation at Harbor-UCLA Medical Center, Torrance, CA, USA. .,Academy of Sport and Physical Activity, Faculty of Health and Wellbeing, Sheffield Hallam University, Sheffield, UK.
| | - Justin D Roberts
- Cambridge Centre for Sport and Exercise Sciences, School of Psychology and Sports Science, Anglia Ruskin University, Cambridge, UK.
| | - Liam Beasley
- Cambridge Centre for Sport and Exercise Sciences, School of Psychology and Sports Science, Anglia Ruskin University, Cambridge, UK
| | - Shaun Chapman
- Cambridge Centre for Sport and Exercise Sciences, School of Psychology and Sports Science, Anglia Ruskin University, Cambridge, UK
| | - Jorge M Pinto
- Cambridge Centre for Sport and Exercise Sciences, School of Psychology and Sports Science, Anglia Ruskin University, Cambridge, UK
| | - Lee Smith
- Cambridge Centre for Sport and Exercise Sciences, School of Psychology and Sports Science, Anglia Ruskin University, Cambridge, UK
| | - Melanie Wiffin
- Cambridge Centre for Sport and Exercise Sciences, School of Psychology and Sports Science, Anglia Ruskin University, Cambridge, UK
| | - Mark Russell
- School of Social and Health Sciences, Leeds Trinity University, Leeds, UK
| | - S Andy Sparks
- Sport Nutrition and Performance Research Group, Department of Sport and Physical Activity, Edge Hill University, Ormskirk, Lancashire, UK
| | | | - John O'Hara
- Carnegie School of Sport, Leeds Beckett University, Leeds, UK
| | - Louise Sutton
- Carnegie School of Sport, Leeds Beckett University, Leeds, UK
| | - Jose Antonio
- College of Health Care Sciences, Nova Southeastern University, Fort Lauderdale, FL, USA
| | - Darryn S Willoughby
- Department of Health, Human Performance, and Recreation, Baylor University, Waco, TX, USA
| | - Michael D Tarpey
- Department of Physiology, Brody School of Medicine, East Carolina University, Greenville, NC, USA
| | - Abbie E Smith-Ryan
- Department of Exercise and Sport Science, University of North Carolina, Chapel Hill, NC, USA
| | - Michael J Ormsbee
- Institute of Sports Sciences & Medicine, Department of Nutrition, Food and Exercise Sciences, Florida State University, Tallahassee, FL, USA.,Discipline of Biokinetics, Exercise and Leisure Sciences, School of Health Sciences, University of KwaZulu-Natal, Durban, South Africa
| | - Todd A Astorino
- Department of Kinesiology, California State University San Marcos, San Marcos, CA, USA
| | - Richard B Kreider
- Department of Health & Kinesiology, Texas A&M University, College Station, TX, USA
| | - Graham R McGinnis
- Kinesiology and Nutrition Sciences, University of Nevada, Las Vegas, NV, USA
| | - Jeffrey R Stout
- College of Health Professions and Sciences, University of Central Florida, Orlando, FL, USA
| | - JohnEric W Smith
- Department of Kinesiology, Mississippi State University, Mississippi, MS, USA
| | - Shawn M Arent
- Department of Exercise Science, University of South Carolina, Columbia, SC, USA
| | - Bill I Campbell
- Exercise Science Program, Performance & Physique Enhancement Laboratory, University of South Florida, Tampa, FL, USA
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28
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Gibson OR, James CA, Mee JA, Willmott AG, Turner G, Hayes M, Maxwell NS. Heat alleviation strategies for athletic performance: A review and practitioner guidelines. Temperature (Austin) 2019; 7:3-36. [PMID: 32166103 PMCID: PMC7053966 DOI: 10.1080/23328940.2019.1666624] [Citation(s) in RCA: 56] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2019] [Revised: 09/06/2019] [Accepted: 09/08/2019] [Indexed: 12/19/2022] Open
Abstract
International competition inevitably presents logistical challenges for athletes. Events such as the Tokyo 2020 Olympic Games require further consideration given historical climate data suggest athletes will experience significant heat stress. Given the expected climate, athletes face major challenges to health and performance. With this in mind, heat alleviation strategies should be a fundamental consideration. This review provides a focused perspective of the relevant literature describing how practitioners can structure male and female athlete preparations for performance in hot, humid conditions. Whilst scientific literature commonly describes experimental work, with a primary focus on maximizing magnitudes of adaptive responses, this may sacrifice ecological validity, particularly for athletes whom must balance logistical considerations aligned with integrating environmental preparation around training, tapering and travel plans. Additionally, opportunities for sophisticated interventions may not be possible in the constrained environment of the athlete village or event arenas. This review therefore takes knowledge gained from robust experimental work, interprets it and provides direction on how practitioners/coaches can optimize their athletes' heat alleviation strategies. This review identifies two distinct heat alleviation themes that should be considered to form an individualized strategy for the athlete to enhance thermoregulatory/performance physiology. First, chronic heat alleviation techniques are outlined, these describe interventions such as heat acclimation, which are implemented pre, during and post-training to prepare for the increased heat stress. Second, acute heat alleviation techniques that are implemented immediately prior to, and sometimes during the event are discussed. Abbreviations: CWI: Cold water immersion; HA: Heat acclimation; HR: Heart rate; HSP: Heat shock protein; HWI: Hot water immersion; LTHA: Long-term heat acclimation; MTHA: Medium-term heat acclimation; ODHA: Once-daily heat acclimation; RH: Relative humidity; RPE: Rating of perceived exertion; STHA: Short-term heat acclimation; TCORE: Core temperature; TDHA: Twice-daily heat acclimation; TS: Thermal sensation; TSKIN: Skin temperature; V̇O2max: Maximal oxygen uptake; WGBT: Wet bulb globe temperature.
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Affiliation(s)
- Oliver R. Gibson
- Centre for Human Performance, Exercise and Rehabilitation (CHPER), Division of Sport, Health and Exercise Sciences, Brunel University London, Uxbridge, UK
| | - Carl A. James
- Institut Sukan Negara (National Sports Institute), Kuala Lumpur, Malaysia
| | - Jessica A. Mee
- School of Sport and Exercise Sciences, University of Worcester, Worcester, UK
| | - Ashley G.B. Willmott
- Cambridge Centre for Sport and Exercise Sciences, Anglia Ruskin University, Cambridge, UK
| | - Gareth Turner
- Bisham Abbey National High-Performance Centre, English Institute of Sport, EIS Performance Centre, Marlow, UK
| | - Mark Hayes
- Environmental Extremes Laboratory, School of Sport and Service Management, University of Brighton, Eastbourne, UK
| | - Neil S. Maxwell
- Environmental Extremes Laboratory, School of Sport and Service Management, University of Brighton, Eastbourne, UK
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29
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Osborne JO, Stewart IB, Beagley KW, Borg DN, Minett GM. Acute glutamine supplementation does not improve 20-km self-paced cycling performance in the heat. Eur J Appl Physiol 2019; 119:2567-2578. [PMID: 31565753 DOI: 10.1007/s00421-019-04234-2] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2019] [Accepted: 09/18/2019] [Indexed: 01/03/2023]
Abstract
INTRODUCTION The premise of this study was to investigate the effect of acute glutamine supplementation on 20 km time trial cycling performance in the heat, neuromuscular function, inflammation and endotoxemia. METHODS Twelve cyclists completed two, 20-km time trials (20TT) in 35 °C (50% relative humidity). Participants ingested either glutamine (GLUT; 0.9 g kg-1 fat-free mass) or a placebo (CON) 60 min before each 20TT. Physiological and perceptual measures were recorded during each 20TT, and neuromuscular function assessed pre- and post-exercise. Venous blood was analysed for endotoxins, markers of gut damage (inflammatory fatty acid binding protein; I-FABP) and inflammatory cytokines (interleukin-6, IL-6; tumour necrosis factor-alpha, TNF-α). Data were analysed using linear mixed models in a Bayesian framework. RESULTS 20TT in the heat increased I-FABP and elevated inflammatory cytokines (IL-6 and TNF-α) compared to pre-exercise values but did not result in endotoxemia. Completion time was not statistically different between conditions (mean difference [95% credible interval] = 11 s [- 23, 44]). Relative to CON, GLUT did not alter any physiological or perceptual measures during the 20TT. CONCLUSION Glutamine supplementation does not improve 20TT performance in the heat or preserve neuromuscular function when compared to a placebo. These findings suggest that glutamine is not an ergogenic aid or prophylactic intervention for heat-induced gut damage during short-duration self-paced exercise in hot environments.
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Affiliation(s)
- John O Osborne
- School of Exercise and Nutrition Sciences, Queensland University of Technology (QUT), Kelvin Grove, 60 Musk Avenue, Brisbane, QLD, 4059, Australia. .,Institute of Health and Biomedical Innovation, Queensland University of Technology (QUT), Brisbane, Australia.
| | - Ian B Stewart
- School of Exercise and Nutrition Sciences, Queensland University of Technology (QUT), Kelvin Grove, 60 Musk Avenue, Brisbane, QLD, 4059, Australia.,Institute of Health and Biomedical Innovation, Queensland University of Technology (QUT), Brisbane, Australia
| | - Kenneth W Beagley
- Institute of Health and Biomedical Innovation, Queensland University of Technology (QUT), Brisbane, Australia.,School of Biomedical Sciences, Queensland University of Technology (QUT), Brisbane, Australia
| | - David N Borg
- School of Exercise and Nutrition Sciences, Queensland University of Technology (QUT), Kelvin Grove, 60 Musk Avenue, Brisbane, QLD, 4059, Australia.,Institute of Health and Biomedical Innovation, Queensland University of Technology (QUT), Brisbane, Australia.,The Hopkins Centre, Menzies Health Institute Queensland, Griffith University, Brisbane, Australia
| | - Geoffrey M Minett
- School of Exercise and Nutrition Sciences, Queensland University of Technology (QUT), Kelvin Grove, 60 Musk Avenue, Brisbane, QLD, 4059, Australia.,Institute of Health and Biomedical Innovation, Queensland University of Technology (QUT), Brisbane, Australia
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30
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Costa RJS, Gaskell SK, McCubbin AJ, Snipe RMJ. Exertional-heat stress-associated gastrointestinal perturbations during Olympic sports: Management strategies for athletes preparing and competing in the 2020 Tokyo Olympic Games. Temperature (Austin) 2019; 7:58-88. [PMID: 32166105 PMCID: PMC7053925 DOI: 10.1080/23328940.2019.1597676] [Citation(s) in RCA: 55] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2019] [Revised: 03/05/2019] [Accepted: 03/14/2019] [Indexed: 12/15/2022] Open
Abstract
Exercise-induced gastrointestinal syndrome (EIGS) is a common characteristic of exercise. The causes appear to be multifactorial in origin, but stem primarily from splanchnic hypoperfusion and increased sympathetic drive. These primary causes can lead to secondary outcomes that include increased intestinal epithelial injury and gastrointestinal hyperpermeability, systemic endotoxemia, and responsive cytokinemia, and impaired gastrointestinal function (i.e. transit, digestion, and absorption). Impaired gastrointestinal integrity and functional responses may predispose individuals, engaged in strenuous exercise, to gastrointestinal symptoms (GIS), and health complications of clinical significance, both of which may have exercise performance implications. There is a growing body of evidence indicating heat exposure during exercise (i.e. exertional-heat stress) can substantially exacerbate these gastrointestinal perturbations, proportionally to the magnitude of exertional-heat stress, which is of major concern for athletes preparing for and competing in the upcoming 2020 Tokyo Olympic Games. To date, various hydration and nutritional strategies have been explored to prevent or ameliorate exertional-heat stress associated gastrointestinal perturbations. The aims of the current review are to comprehensively explore the impact of exertional-heat stress on markers of EIGS, examine the evidence for the prevention and (or) management of EIGS in relation to exertional-heat stress, and establish best-practice nutritional recommendations for counteracting EIGS and associated GIS in athletes preparing for and competing in Tokyo 2020.
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Affiliation(s)
- Ricardo J S Costa
- Monash University, Department of Nutrition Dietetics and Food, Notting Hill, Victoria, Australia
| | - Stephanie K Gaskell
- Monash University, Department of Nutrition Dietetics and Food, Notting Hill, Victoria, Australia
| | - Alan J McCubbin
- Monash University, Department of Nutrition Dietetics and Food, Notting Hill, Victoria, Australia
| | - Rhiannon M J Snipe
- Deakin University, Centre for Sport Research, School of Exercise and Nutrition Science, Burwood, Victoria, Australia
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Leech B, Schloss J, Steel A. Treatment Interventions for the Management of Intestinal Permeability: A Cross-Sectional Survey of Complementary and Integrative Medicine Practitioners. J Altern Complement Med 2019; 25:623-636. [PMID: 31038350 DOI: 10.1089/acm.2018.0374] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Objectives: This study aims to explore the treatment interventions complementary and integrative medicine (CIM) practitioners use in the management of an emerging health condition, increased intestinal permeability (IP), and the association these methods have on the observed time to resolve this condition. Design and setting: A cross-sectional survey of Australian naturopaths, nutritionists, and Western herbal medicine practitioners was undertaken (n = 227) through the Practitioner Research and Collaboration Initiative (PRACI) network. Outcome measures: Frequencies and percentages of the treatment methods, including chi-square analysis to examine the associations between treatment methods and observed time to resolve IP. Results: Thirty-six CIM practitioners responded to the survey (response rate 15.9%). CIM practitioners were found to use a multimodal approach in the management of IP with 92.6% of respondents using three or more categories of treatment interventions (nutritional, herbal, dietary, and lifestyle) with a mean total of 43.0 ± 24.89 single treatment interventions frequently prescribed. The main treatments prescribed in the management of IP were zinc (85.2%), probiotics: multistrain (77.8%), vitamin D (75.0%), glutamine (73.1%), Curcuma longa (73.1%), and Saccharomyces boulardii (70.4%). CIM practitioners also advocate patients with IP to reduce alcohol (96.3%), gluten (85.2%), and dairy (75.0%) consumption. Evaluation of antibiotics (75.0%) and nonsteroidal anti-inflammatory drugs (73.1%) prescriptions were frequently advised by CIM practitioners. A longer observed time to resolve IP was seen in CIM practitioners who did not reduce intense exercise in the management of IP (p = 0.02). Conclusions: This study represents the first survey of the treatments prescribed by CIM practitioners for IP and suggests that CIM practitioners use numerous integrative treatment methods for the management of IP. The treatment interventions frequently prescribed by CIM practitioners align with preclinical research, suggesting that CIM practitioners prescribe in accordance with the published literature. The findings of this study contribute to the implementation of clinical research in the management of IP, which considers multiple concurrent treatments.
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Affiliation(s)
- Bradley Leech
- 1 Office of Research, Endeavour College of Natural Health, Fortitude Valley, QLD, Australia.,2 Australian Research Centre in Complementary and Integrative Medicine, Faculty of Health, University of Technology Sydney, Ultimo, NSW, Australia
| | - Janet Schloss
- 1 Office of Research, Endeavour College of Natural Health, Fortitude Valley, QLD, Australia
| | - Amie Steel
- 1 Office of Research, Endeavour College of Natural Health, Fortitude Valley, QLD, Australia.,2 Australian Research Centre in Complementary and Integrative Medicine, Faculty of Health, University of Technology Sydney, Ultimo, NSW, Australia
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Four weeks of probiotic supplementation reduces GI symptoms during a marathon race. Eur J Appl Physiol 2019; 119:1491-1501. [PMID: 30982100 PMCID: PMC6570661 DOI: 10.1007/s00421-019-04136-3] [Citation(s) in RCA: 63] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2019] [Accepted: 04/01/2019] [Indexed: 12/14/2022]
Abstract
Purpose To evaluate the effects of probiotic supplementation on gastrointestinal (GI) symptoms, circulatory markers of GI permeability, damage, and markers of immune response during a marathon race. Methods Twenty-four recreational runners were randomly assigned to either supplement with a probiotic (PRO) capsule [25 billion CFU Lactobacillus acidophilus (CUL60 and CUL21), Bifidobacterium bifidum (CUL20), and Bifidobacterium animalis subs p. Lactis (CUL34)] or placebo (PLC) for 28 days prior to a marathon race. GI symptoms were recorded during the supplement period and during the race. Serum lactulose:rhamnose ratio, and plasma intestinal-fatty acid binding protein, sCD14, and cytokines were measured pre- and post-races. Results Prevalence of moderate GI symptoms reported were lower during the third and fourth weeks of the supplement period compared to the first and second weeks in PRO (p < 0.05) but not PLC (p > 0.05). During the marathon, GI symptom severity during the final third was significantly lower in PRO compared to PLC (p = 0.010). The lower symptom severity was associated with a significant difference in reduction of average speed from the first to the last third of the race between PLC (− 14.2 ± 5.8%) and PRO (− 7.9 ± 7.5%) (p = 0.04), although there was no difference in finish times between groups (p > 0.05). Circulatory measures increased to a similar extent between PRO and PLC (p > 0.05). Conclusion Probiotics supplementation was associated with a lower incidence and severity of GI symptoms in marathon runners, although the exact mechanisms are yet to be elucidated. Reducing GI symptoms during marathon running may help maintain running pace during the latter stages of racing.
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Kartaram S, Mensink M, Teunis M, Schoen E, Witte G, Janssen Duijghuijsen L, Verschuren M, Mohrmann K, M'Rabet L, Knipping K, Wittink H, van Helvoort A, Garssen J, Witkamp R, Pieters R, van Norren K. Plasma citrulline concentration, a marker for intestinal functionality, reflects exercise intensity in healthy young men. Clin Nutr 2018; 38:2251-2258. [PMID: 30340895 DOI: 10.1016/j.clnu.2018.09.029] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2018] [Revised: 09/04/2018] [Accepted: 09/24/2018] [Indexed: 10/28/2022]
Abstract
BACKGROUND & AIMS Plasma citrulline concentration is considered to be a marker for enterocyte metabolic mass and to reflect its reduction as may occur during intestinal dysfunction. Strenuous exercise can act as a stressor to induce small intestinal injury. Our previous studies suggest that this comprises the intestinal ability to produce citrulline from a glutamine-rich protein bolus. In this study we investigated the effects of different exercise intensities and hydration state on citrulline and iFABP levels following a post-exercise glutamine bolus in healthy young men. METHODS Fifteen healthy young men (20-35 yrs, VO2 max 56.9 ± 3.9 ml kg-1 min-1) performed in a randomly assigned cross-over design, a rest (protocol 1) and four cycle ergometer protocols. The volunteers cycled submaximal at different percentages of their individual pre-assessed maximum workload (Wmax): 70% Wmax in hydrated (protocol 2) and dehydrated state (protocol 3), 50% Wmax (protocol 4) and intermittent 85/55% Wmax in blocks of 2 min (protocol 5). Immediately after 1 h exercise or rest, subjects were given a glutamine bolus with added alanine as an iso-caloric internal standard (7.5 g of each amino acid). Blood samples were collected before, during and after rest or exercise, up to 24 h post onset of the experiment. Amino acids and urea were analysed as metabolic markers, creatine phosphokinase and iFABP as markers of muscle and intestinal damage, respectively. Data were analysed using a multilevel mixed linear statistical model. p values were corrected for multiple testing. RESULTS Citrulline levels already increased before glutamine supplementation during normal hydrated exercise, while this was not observed in the dehydrated and rest protocols. The low intensity exercise protocol (50% Wmax) showed the highest increase in citrulline levels both during exercise (43.83 μmol/L ± 2.63 (p < 0.001)) and after glutamine consumption (50.54 μmol/L ± 2.62) compared to the rest protocol (28.97 μmol/L ± 1.503 and 41.65 μmol/L ± 1.96, respectively, p < 0.05). However, following strenuous exercise at 70% Wmax in the dehydrated state, citrulline levels did not increase during exercise and less after the glutamine consumption when compared to the resting condition and hydrated protocols. In line with this, serum iFABP levels were the highest with the strenuous dehydrated protocol (1443.72 μmol/L ± 249.9, p < 0.001), followed by the high intensity exercise at 70% Wmax in the hydrated condition. CONCLUSIONS Exercise induces an increase in plasma citrulline, irrespective of a glutamine bolus. The extent to which this occurs is dependent on exercise intensity and the hydration state of the subjects. The same holds true for both the post-exercise increase in citrulline levels following glutamine supplementation and serum iFABP levels. These data indicate that citrulline release during exercise and after an oral glutamine bolus might be dependent on the intestinal health state and therefore on intestinal functionality. Glutamine is known to play a major role in intestinal physiology and the maintenance of gut health and barrier function. Together, this suggests that in clinical practice, a glutamine bolus to increase citrulline levels after exercise might be preferable compared to supplementing citrulline itself. To our knowledge this is the first time that exercise workload-related effects on plasma citrulline are reported in relation to intestinal damage.
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Affiliation(s)
- Shirley Kartaram
- Research Group Innovative Testing in Life Sciences and Chemistry, University of Applied Sciences Utrecht, The Netherlands
| | - Marco Mensink
- Division Human Nutrition, Wageningen University & Research, Wageningen, The Netherlands
| | - Marc Teunis
- Research Group Innovative Testing in Life Sciences and Chemistry, University of Applied Sciences Utrecht, The Netherlands
| | - Eric Schoen
- Netherlands Organization for Applied Scientific Research (TNO), Zeist, The Netherlands
| | | | | | - Martie Verschuren
- Research Group Analysis Techniques in the Life Sciences, Avans University of Applied Sciences, Breda, The Netherlands
| | | | - Laura M'Rabet
- Research Group Innovative Testing in Life Sciences and Chemistry, University of Applied Sciences Utrecht, The Netherlands
| | | | - Harriet Wittink
- Research Group Lifestyle and Health, University of Applied Sciences Utrecht, The Netherlands
| | - Ardy van Helvoort
- Nutricia Research, Utrecht, The Netherlands; School of Nutrition and Translational Research in Metabolism (NUTRIM), Maastricht University, The Netherlands
| | - Johan Garssen
- Department of Pharmaceutical Sciences, Utrecht University, Utrecht, The Netherlands; Nutricia Research, Utrecht, The Netherlands
| | - Renger Witkamp
- Division Human Nutrition, Wageningen University & Research, Wageningen, The Netherlands
| | - Raymond Pieters
- Research Group Innovative Testing in Life Sciences and Chemistry, University of Applied Sciences Utrecht, The Netherlands; Institute for Risk Assessment Sciences, Immunotoxicology (IRAS), Utrecht University, Utrecht, The Netherlands
| | - Klaske van Norren
- Division Human Nutrition, Wageningen University & Research, Wageningen, The Netherlands.
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Nutrition and Supplementation Considerations to Limit Endotoxemia When Exercising in the Heat. Sports (Basel) 2018; 6:sports6010012. [PMID: 29910316 PMCID: PMC5969196 DOI: 10.3390/sports6010012] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2017] [Revised: 01/25/2018] [Accepted: 01/31/2018] [Indexed: 02/07/2023] Open
Abstract
Exercise-induced heat production is further elevated by exercise performed in hot conditions and this can subsequently impact inflammation, and gastrointestinal (GI) health. Implementing nutrition and supplementation strategies under these conditions may support the hyperthermic response, the systemic inflammatory response, GI permeability and integrity, and exercise performance. Therefore, the aim of this brief review is to explore athletes' inflammatory response of two key biomarkers, lipopolysaccharide (LPS), and interleukin-6 (IL-6), and provide nutrition and supplementation recommendations when exercising in hot conditions. There is emerging evidence that probiotics, glutamine, and vitamin C can preserve GI integrity, which may improve performance during exercise in the heat. Glucose rich food when consumed with water, before and during exercise in the heat, also appear to limit endotoxemia, preserve GI integrity, and reduce the incidence of GI disturbances compared with water alone. The use of non-steroidal anti-inflammatory drugs (NSAIDs) may compromise GI integrity and this may result in greater leakage of endotoxins during long duration exercise in the heat. Further work is required to elucidate the impact of nutrition and supplementation strategies, in particular the use of NSAIDs, when exercising in the heat.
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