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Zhao ML, Lu ZJ, Yang L, Ding S, Gao F, Liu YZ, Yang XL, Li X, He SY. The cardiovascular system at high altitude: A bibliometric and visualization analysis. World J Cardiol 2024; 16:199-214. [PMID: 38690218 PMCID: PMC11056872 DOI: 10.4330/wjc.v16.i4.199] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/22/2023] [Revised: 02/14/2024] [Accepted: 04/01/2024] [Indexed: 04/23/2024] Open
Abstract
BACKGROUND When exposed to high-altitude environments, the cardiovascular system undergoes various changes, the performance and mechanisms of which remain controversial. AIM To summarize the latest research advancements and hot research points in the cardiovascular system at high altitude by conducting a bibliometric and visualization analysis. METHODS The literature was systematically retrieved and filtered using the Web of Science Core Collection of Science Citation Index Expanded. A visualization analysis of the identified publications was conducted employing CiteSpace and VOSviewer. RESULTS A total of 1674 publications were included in the study, with an observed annual increase in the number of publications spanning from 1990 to 2022. The United States of America emerged as the predominant contributor, while Universidad Peruana Cayetano Heredia stood out as the institution with the highest publication output. Notably, Jean-Paul Richalet demonstrated the highest productivity among researchers focusing on the cardiovascular system at high altitude. Furthermore, Peter Bärtsch emerged as the author with the highest number of cited articles. Keyword analysis identified hypoxia, exercise, acclimatization, acute and chronic mountain sickness, pulmonary hypertension, metabolism, and echocardiography as the primary research hot research points and emerging directions in the study of the cardiovascular system at high altitude. CONCLUSION Over the past 32 years, research on the cardiovascular system in high-altitude regions has been steadily increasing. Future research in this field may focus on areas such as hypoxia adaptation, metabolism, and cardiopulmonary exercise. Strengthening interdisciplinary and multi-team collaborations will facilitate further exploration of the pathophysiological mechanisms underlying cardiovascular changes in high-altitude environments and provide a theoretical basis for standardized disease diagnosis and treatment.
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Affiliation(s)
- Mao-Lin Zhao
- Department of Cardiovascular Surgery, The General Hospital of Western Theater Command, College of Medicine, Southwest Jiaotong University, Chengdu 610083, Sichuan Province, China
| | - Zhong-Jie Lu
- Department of Cardiovascular Surgery, The General Hospital of Western Theater Command, College of Medicine, Southwest Jiaotong University, Chengdu 610083, Sichuan Province, China
| | - Li Yang
- Department of Cardiovascular Surgery, The General Hospital of Western Theater Command, College of Medicine, Southwest Jiaotong University, Chengdu 610083, Sichuan Province, China
| | - Sheng Ding
- Department of Cardiovascular Surgery, The General Hospital of Western Theater Command, College of Medicine, Southwest Jiaotong University, Chengdu 610083, Sichuan Province, China
| | - Feng Gao
- Department of Cardiovascular Surgery, The General Hospital of Western Theater Command, College of Medicine, Southwest Jiaotong University, Chengdu 610083, Sichuan Province, China
| | - Yuan-Zhang Liu
- Department of Cardiovascular Surgery, The General Hospital of Western Theater Command, College of Medicine, Southwest Jiaotong University, Chengdu 610083, Sichuan Province, China
| | - Xue-Lin Yang
- Department of Cardiovascular Surgery, The General Hospital of Western Theater Command, College of Medicine, Southwest Jiaotong University, Chengdu 610083, Sichuan Province, China
| | - Xia Li
- Department of Cardiovascular Surgery, The General Hospital of Western Theater Command, College of Medicine, Southwest Jiaotong University, Chengdu 610083, Sichuan Province, China
| | - Si-Yi He
- Department of Cardiovascular Surgery, The General Hospital of Western Theater Command, Chengdu 610083, Sichuan Province, China.
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Dellavechia de Carvalho C, Marcolino Putti G, Figueiredo Foresti Y, Alves Ribeiro F, Causin Andreossi J, Ferraz de Campos G, Papoti M. Recovery in normobaric hypoxia as an additional stimulus for high-intensity intermittent training. Sci Sports 2023. [DOI: 10.1016/j.scispo.2021.12.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
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Behrendt T, Bielitzki R, Behrens M, Herold F, Schega L. Effects of Intermittent Hypoxia-Hyperoxia on Performance- and Health-Related Outcomes in Humans: A Systematic Review. SPORTS MEDICINE - OPEN 2022; 8:70. [PMID: 35639211 PMCID: PMC9156652 DOI: 10.1186/s40798-022-00450-x] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/14/2021] [Accepted: 04/17/2022] [Indexed: 02/07/2023]
Abstract
BACKGROUND Intermittent hypoxia applied at rest or in combination with exercise promotes multiple beneficial adaptations with regard to performance and health in humans. It was hypothesized that replacing normoxia by moderate hyperoxia can increase the adaptive response to the intermittent hypoxic stimulus. OBJECTIVE Our objective was to systematically review the current state of the literature on the effects of chronic intermittent hypoxia-hyperoxia (IHH) on performance- and health-related outcomes in humans. METHODS PubMed, Web of Science™, Scopus, and Cochrane Library databases were searched in accordance with PRISMA guidelines (January 2000 to September 2021) using the following inclusion criteria: (1) original research articles involving humans, (2) investigation of the chronic effect of IHH, (3) inclusion of a control group being not exposed to IHH, and (4) articles published in peer-reviewed journals written in English. RESULTS Of 1085 articles initially found, eight studies were included. IHH was solely performed at rest in different populations including geriatric patients (n = 1), older patients with cardiovascular (n = 3) and metabolic disease (n = 2) or cognitive impairment (n = 1), and young athletes with overtraining syndrome (n = 1). The included studies confirmed the beneficial effects of chronic exposure to IHH, showing improvements in exercise tolerance, peak oxygen uptake, and global cognitive functions, as well as lowered blood glucose levels. A trend was discernible that chronic exposure to IHH can trigger a reduction in systolic and diastolic blood pressure. The evidence of whether IHH exerts beneficial effects on blood lipid levels and haematological parameters is currently inconclusive. A meta-analysis was not possible because the reviewed studies had a considerable heterogeneity concerning the investigated populations and outcome parameters. CONCLUSION Based on the published literature, it can be suggested that chronic exposure to IHH might be a promising non-pharmacological intervention strategy for improving peak oxygen consumption, exercise tolerance, and cognitive performance as well as reducing blood glucose levels, and systolic and diastolic blood pressure in older patients with cardiovascular and metabolic diseases or cognitive impairment. However, further randomized controlled trials with adequate sample sizes are needed to confirm and extend the evidence. This systematic review was registered on the international prospective register of systematic reviews (PROSPERO-ID: CRD42021281248) ( https://www.crd.york.ac.uk/prospero/ ).
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Affiliation(s)
- Tom Behrendt
- Department of Sport Science, Chair for Health and Physical Activity, Otto-von-Guericke University Magdeburg, Universitätsplatz 2, 39104 Magdeburg, Germany
| | - Robert Bielitzki
- Department of Sport Science, Chair for Health and Physical Activity, Otto-von-Guericke University Magdeburg, Universitätsplatz 2, 39104 Magdeburg, Germany
| | - Martin Behrens
- Department of Sport Science, Chair for Health and Physical Activity, Otto-von-Guericke University Magdeburg, Universitätsplatz 2, 39104 Magdeburg, Germany
- Department of Orthopaedics, Rostock University Medical Center, Doberaner Str. 142, 18057 Rostock, Germany
| | - Fabian Herold
- Research Group Degenerative and Chronic Disease, Movement, Faculty of Health Sciences, University of Potsdam, Karl-Liebknecht-Str. 24-25, 14476 Potsdam, Germany
| | - Lutz Schega
- Department of Sport Science, Chair for Health and Physical Activity, Otto-von-Guericke University Magdeburg, Universitätsplatz 2, 39104 Magdeburg, Germany
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Ghiani G, Doneddu A, Sechi F, Mulliri G, Roberto S, Crisafulli A. Case study: physical capacity and nutritional status before and after climbing two peaks with different altitude (4897-6812 m). J Sports Med Phys Fitness 2020; 61:1309-1313. [PMID: 33269886 DOI: 10.23736/s0022-4707.20.11682-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Vinson and Ama Dablam are summits of different altitudes (4897 and 6812 m respectively). There are no published studies comparing physiological adaptations occurring after climbing both peaks yet. This case study compares changes in certain physiological parameters and body composition of a mountaineer who ascended both peaks. The athlete was a mountaineer who already climbed the 7 Summits©. Baseline body composition, physical capacity, and cerebral oxygenation during effort were measured before and after his departure. Body composition was estimated by electrical bio-impedance, while physical capacity was measured with an incremental exercise test (treadmill) conducted in normoxia and in hypoxia corresponding to about 4000 m. Hypoxia was obtained with a hypoxic gas generator. During tests, cerebral oxygenation was estimated with near infrared spectroscopy. The ascent of mount Vinson and Ama Dablam took 4 and 15 days respectively. The ascent of mount Vinson resulted in a 2.0 kg drop in body mass and a reduction in body fat (from 15.5% to 12.1%). The ascent of Ama Dablam reduced body mass by 3.7 kg, with an increase in body fat from 11.9% to 14.7%. Physical capacity was almost unchanged after both expeditions, although there was a reduction in maximum heart rate in relation to workload after Ama Dablam. Finally, after Ama Dablam there was an increase in cerebral oxygenation during effort both in normoxia and hypoxia. It was concluded that the longer duration and the higher altitude during the Ama Dablam expedition resulted in more evident physiological changes.
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Affiliation(s)
- Giovanna Ghiani
- Department of Medical Sciences and Public Health, Sports Physiology Laboratory, University of Cagliari, Cagliari, Italy -
| | - Azzurra Doneddu
- Department of Medical Sciences and Public Health, Sports Physiology Laboratory, University of Cagliari, Cagliari, Italy
| | - Fabio Sechi
- Department of Medical Sciences and Public Health, Sports Physiology Laboratory, University of Cagliari, Cagliari, Italy
| | - Gabriele Mulliri
- Department of Medical Sciences and Public Health, Sports Physiology Laboratory, University of Cagliari, Cagliari, Italy
| | - Silvana Roberto
- Department of Medical Sciences and Public Health, Sports Physiology Laboratory, University of Cagliari, Cagliari, Italy
| | - Antonio Crisafulli
- Department of Medical Sciences and Public Health, Sports Physiology Laboratory, University of Cagliari, Cagliari, Italy
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Girard O, Goods PSR, Brocherie F. Editorial: Elevating Sport Performance to New Heights With Innovative 'Live Low - Train High' Altitude Training. Front Sports Act Living 2020; 2:108. [PMID: 33345097 PMCID: PMC7739611 DOI: 10.3389/fspor.2020.00108] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2020] [Accepted: 07/20/2020] [Indexed: 12/14/2022] Open
Affiliation(s)
- Olivier Girard
- School of Human Sciences, Exercise and Sport Science, University of Western Australia, Perth, WA, Australia
| | - Paul S R Goods
- School of Human Sciences, Exercise and Sport Science, University of Western Australia, Perth, WA, Australia.,Western Australian Institute of Sport, Perth, WA, Australia
| | - Franck Brocherie
- Laboratory Sport, Expertise and Performance, EA 7370, French Institute of Sport (INSEP), Paris, France
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Girard O, Brocherie F, Goods PSR, Millet GP. An Updated Panorama of "Living Low-Training High" Altitude/Hypoxic Methods. Front Sports Act Living 2020; 2:26. [PMID: 33345020 PMCID: PMC7739748 DOI: 10.3389/fspor.2020.00026] [Citation(s) in RCA: 35] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2020] [Accepted: 03/06/2020] [Indexed: 12/16/2022] Open
Abstract
With minimal costs and travel constraints for athletes, the “living low-training high” (LLTH) approach is becoming an important intervention for modern sport. The popularity of the LLTH model of altitude training is also associated with the fact that it only causes a slight disturbance to athletes' usual daily routine, allowing them to maintain their regular lifestyle in their home environment. In this perspective article, we discuss the evolving boundaries of the LLTH paradigm and its practical applications for athletes. Passive modalities include intermittent hypoxic exposure at rest (IHE) and Ischemic preconditioning (IPC). Active modalities use either local [blood flow restricted (BFR) exercise] and/or systemic hypoxia [continuous low-intensity training in hypoxia (CHT), interval hypoxic training (IHT), repeated-sprint training in hypoxia (RSH), sprint interval training in hypoxia (SIH) and resistance training in hypoxia (RTH)]. A combination of hypoxic methods targeting different attributes also represents an attractive solution. In conclusion, a growing number of LLTH altitude training methods exists that include the application of systemic and local hypoxia stimuli, or a combination of both, for performance enhancement in many disciplines.
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Affiliation(s)
- Olivier Girard
- School of Human Sciences, Exercise and Sport Science, University of Western Australia, Perth, WA, Australia
| | - Franck Brocherie
- Laboratory Sport, Expertise and Performance, EA 7370, French Institute of Sport (INSEP), Paris, France
| | - Paul S R Goods
- School of Human Sciences, Exercise and Sport Science, University of Western Australia, Perth, WA, Australia.,Western Australian Institute of Sport (WAIS), Perth, WA, Australia
| | - Gregoire P Millet
- Faculty of Biology and Medicine, Institute of Sport Sciences, University of Lausanne, Lausanne, Switzerland
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7
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Suzuki J. Effects of exercise training with short-duration intermittent hypoxia on endurance performance and muscle metabolism in well-trained mice. Physiol Rep 2019; 7:e14182. [PMID: 31328438 PMCID: PMC6643079 DOI: 10.14814/phy2.14182] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2019] [Revised: 06/19/2019] [Accepted: 06/24/2019] [Indexed: 01/16/2023] Open
Abstract
The author previously reported that short-duration intermittent hypoxia had additive effects on improvements in endurance capacity by enhancing fatty acid metabolism. The present study was designed to investigate the effects of short-duration intermittent hypoxia on endurance capacity, metabolic enzyme activity, and protein levels associated with mitochondrial biogenesis in well-trained mice. Mice in the training group were housed in a cage with a running wheel for 7 weeks from 5 weeks old. Voluntary running markedly increased maximal work values by 5.0-fold. Trained mice were then subjected to either endurance treadmill training (ET) for 60 min or hybrid training (HT, ET for 30 min followed by sprint interval exercise (5-sec run-10-sec rest) for 30 min) with (H-ET or H-HT) or without (ET or HT) short-duration intermittent hypoxia (4 cycles of 12-13% O2 for 15 min and 20.9% O2 for 10 min) for 4 weeks. Maximal endurance capacity was markedly greater in the H-ET and H-HT than ET and HT groups, respectively. H-ET and H-HT increased activity levels of 3-hydroxyacyl-CoA-dehydrogenase in oxidative muscle portion and pyruvate dehydrogenase complex in glycolytic muscle portion. These activity levels were significantly correlated with maximal endurance capacity. Protein levels of dynamin-related protein-1 were increased more by H-ET and H-HT than by ET and HT, but were not significantly correlated with maximal work. These results suggest that intermittent hypoxic exposure has beneficial effects on endurance and hybrid training to improve the endurance capacity via improving fatty acid and pyruvate oxidation in highly trained mice.
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Affiliation(s)
- Junichi Suzuki
- Laboratory of Exercise Physiology, Health and Sports Sciences, Course of Sports Education, Department of EducationHokkaido University of EducationIwamizawaHokkaidoJapan
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8
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Girard O, Brocherie F, Millet GP. Effects of Altitude/Hypoxia on Single- and Multiple-Sprint Performance: A Comprehensive Review. Sports Med 2018; 47:1931-1949. [PMID: 28451905 DOI: 10.1007/s40279-017-0733-z] [Citation(s) in RCA: 84] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Many sport competitions, typically involving the completion of single- (e.g. track-and-field or track cycling events) and multiple-sprint exercises (e.g. team and racquet sports, cycling races), are staged at terrestrial altitudes ranging from 1000 to 2500 m. Our aim was to comprehensively review the current knowledge on the responses to either acute or chronic altitude exposure relevant to single and multiple sprints. Performance of a single sprint is generally not negatively affected by acute exposure to simulated altitude (i.e. normobaric hypoxia) because an enhanced anaerobic energy release compensates for the reduced aerobic adenosine triphosphate production. Conversely, the reduction in air density in terrestrial altitude (i.e. hypobaric hypoxia) leads to an improved sprinting performance when aerodynamic drag is a limiting factor. With the repetition of maximal efforts, however, repeated-sprint ability is more altered (i.e. with earlier and larger performance decrements) at high altitudes (>3000-3600 m or inspired fraction of oxygen <14.4-13.3%) compared with either normoxia or low-to-moderate altitudes (<3000 m or inspired fraction of oxygen >14.4%). Traditionally, altitude training camps involve chronic exposure to low-to-moderate terrestrial altitudes (<3000 m or inspired fraction of oxygen >14.4%) for inducing haematological adaptations. However, beneficial effects on sprint performance after such altitude interventions are still debated. Recently, innovative 'live low-train high' methods, in isolation or in combination with hypoxic residence, have emerged with the belief that up-regulated non-haematological peripheral adaptations may further improve performance of multiple sprints compared with similar normoxic interventions.
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Affiliation(s)
- Olivier Girard
- Aspetar Orthopaedic and Sports Medicine Hospital, Athlete Health and Performance Research Centre, Doha, Qatar.
- ISSUL, Institute of Sport Sciences, University of Lausanne, Lausanne, Switzerland.
| | - Franck Brocherie
- Laboratory Sport, Expertise and Performance (EA 7370), Research Department, French Institute of Sport (INSEP), Paris, France
- ISSUL, Institute of Sport Sciences, University of Lausanne, Lausanne, Switzerland
| | - Grégoire P Millet
- ISSUL, Institute of Sport Sciences, University of Lausanne, Lausanne, Switzerland
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9
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Viscor G, Torrella JR, Corral L, Ricart A, Javierre C, Pages T, Ventura JL. Physiological and Biological Responses to Short-Term Intermittent Hypobaric Hypoxia Exposure: From Sports and Mountain Medicine to New Biomedical Applications. Front Physiol 2018; 9:814. [PMID: 30038574 PMCID: PMC6046402 DOI: 10.3389/fphys.2018.00814] [Citation(s) in RCA: 64] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2018] [Accepted: 06/11/2018] [Indexed: 12/14/2022] Open
Abstract
In recent years, the altitude acclimatization responses elicited by short-term intermittent exposure to hypoxia have been subject to renewed attention. The main goal of short-term intermittent hypobaric hypoxia exposure programs was originally to improve the aerobic capacity of athletes or to accelerate the altitude acclimatization response in alpinists, since such programs induce an increase in erythrocyte mass. Several model programs of intermittent exposure to hypoxia have presented efficiency with respect to this goal, without any of the inconveniences or negative consequences associated with permanent stays at moderate or high altitudes. Artificial intermittent exposure to normobaric hypoxia systems have seen a rapid rise in popularity among recreational and professional athletes, not only due to their unbeatable cost/efficiency ratio, but also because they help prevent common inconveniences associated with high-altitude stays such as social isolation, nutritional limitations, and other minor health and comfort-related annoyances. Today, intermittent exposure to hypobaric hypoxia is known to elicit other physiological response types in several organs and body systems. These responses range from alterations in the ventilatory pattern to modulation of the mitochondrial function. The central role played by hypoxia-inducible factor (HIF) in activating a signaling molecular cascade after hypoxia exposure is well known. Among these targets, several growth factors that upregulate the capillary bed by inducing angiogenesis and promoting oxidative metabolism merit special attention. Applying intermittent hypobaric hypoxia to promote the action of some molecules, such as angiogenic factors, could improve repair and recovery in many tissue types. This article uses a comprehensive approach to examine data obtained in recent years. We consider evidence collected from different tissues, including myocardial capillarization, skeletal muscle fiber types and fiber size changes induced by intermittent hypoxia exposure, and discuss the evidence that points to beneficial interventions in applied fields such as sport science. Short-term intermittent hypoxia may not only be useful for healthy people, but could also be considered a promising tool to be applied, with due caution, to some pathophysiological states.
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Affiliation(s)
- Ginés Viscor
- Physiology Section, Department of Cell Biology, Physiology and Immunology, Faculty of Biology, Universitat de Barcelona, Barcelona, Spain
| | - Joan R. Torrella
- Physiology Section, Department of Cell Biology, Physiology and Immunology, Faculty of Biology, Universitat de Barcelona, Barcelona, Spain
| | - Luisa Corral
- Exercise Physiology Unit, Department of Physiological Sciences, Faculty of Medicine and Health Sciences, Universitat de Barcelona, L'Hospitalet de Llobregat, Barcelona, Spain
| | - Antoni Ricart
- Exercise Physiology Unit, Department of Physiological Sciences, Faculty of Medicine and Health Sciences, Universitat de Barcelona, L'Hospitalet de Llobregat, Barcelona, Spain
| | - Casimiro Javierre
- Exercise Physiology Unit, Department of Physiological Sciences, Faculty of Medicine and Health Sciences, Universitat de Barcelona, L'Hospitalet de Llobregat, Barcelona, Spain
| | - Teresa Pages
- Physiology Section, Department of Cell Biology, Physiology and Immunology, Faculty of Biology, Universitat de Barcelona, Barcelona, Spain
| | - Josep L. Ventura
- Exercise Physiology Unit, Department of Physiological Sciences, Faculty of Medicine and Health Sciences, Universitat de Barcelona, L'Hospitalet de Llobregat, Barcelona, Spain
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Turner G, Fudge BW, Pringle JSM, Maxwell NS, Richardson AJ. Altitude training in endurance running: perceptions of elite athletes and support staff. J Sports Sci 2018; 37:163-172. [PMID: 29932816 DOI: 10.1080/02640414.2018.1488383] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Abstract
This study sought to establish perceptions of elite endurance athletes on the role and worth of altitude training. Elite British endurance runners were surveyed to identify the altitude and hypoxic training methods utilised, along with reasons for use, and any situational, cultural and behaviour factors influencing these. Prior to the 2012 Olympics Games, 39 athletes and 20 support staff (coaches/practitioners) completed an internet-based survey to establish differences between current practices and the accepted "best-practice". Almost all of the athletes (98%) and support staff (95%) surveyed had utilised altitude and hypoxic training, or had advised it to athletes. 75% of athletes believed altitude and hypoxia to be a "very important" factor in their training regime, with 50% of support staff believing the same. Athletes and support staff were in agreement of the methods of altitude training utilised (i.e. 'hypoxic dose' and strategy), with camps lasting 3-4 weeks at 1,500-2,500 m being the most popular. Athletes and support staff are utilising altitude and hypoxic training methods in a manner agreeing with research-based suggestions. The survey identified a number of specific challenges and priorities, which could provide scope to optimise future altitude training methods for endurance performance in these elite groups.
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Affiliation(s)
- Gareth Turner
- a Centre for Sport and Exercise Science and Medicine (SESAME) , University of Brighton , Eastbourne , UK.,c EIS Performance Centre , Loughborough University , Loughborough , UK
| | - Barry W Fudge
- b National Performance Centre , Loughborough University , Loughborough , UK
| | - Jamie S M Pringle
- c EIS Performance Centre , Loughborough University , Loughborough , UK
| | - Neil S Maxwell
- a Centre for Sport and Exercise Science and Medicine (SESAME) , University of Brighton , Eastbourne , UK
| | - Alan J Richardson
- a Centre for Sport and Exercise Science and Medicine (SESAME) , University of Brighton , Eastbourne , UK
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11
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Lizamore CA, Hamlin MJ. The Use of Simulated Altitude Techniques for Beneficial Cardiovascular Health Outcomes in Nonathletic, Sedentary, and Clinical Populations: A Literature Review. High Alt Med Biol 2017; 18:305-321. [PMID: 28846046 DOI: 10.1089/ham.2017.0050] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Lizamore, Catherine A., and Michael J. Hamlin. The use of simulated altitude techniques for beneficial cardiovascular health outcomes in nonathletic, sedentary, and clinical populations: A literature review. High Alt Med Biol 18:305-321, 2017. BACKGROUND The reportedly beneficial improvements in an athlete's physical performance following altitude training may have merit for individuals struggling to meet physical activity guidelines. AIM To review the effectiveness of simulated altitude training methodologies at improving cardiovascular health in sedentary and clinical cohorts. METHODS Articles were selected from Science Direct, PubMed, and Google Scholar databases using a combination of the following search terms anywhere in the article: "intermittent hypoxia," "intermittent hypoxic," "normobaric hypoxia," or "altitude," and a participant descriptor including the following: "sedentary," "untrained," or "inactive." RESULTS 1015 articles were returned, of which 26 studies were accepted (4 clinical cohorts, 22 studies used sedentary participants). Simulated altitude methodologies included prolonged hypoxic exposure (PHE: continuous hypoxic interval), intermittent hypoxic exposure (IHE: 5-10 minutes hypoxic:normoxic intervals), and intermittent hypoxic training (IHT: exercising in hypoxia). CONCLUSIONS In a clinical cohort, PHE for 3-4 hours at 2700-4200 m for 2-3 weeks may improve blood lipid profile, myocardial perfusion, and exercise capacity, while 3 weeks of IHE treatment may improve baroreflex sensitivity and heart rate variability. In the sedentary population, IHE was most likely to improve submaximal exercise tolerance, time to exhaustion, and heart rate variability. Hematological adaptations were unclear. Typically, a 4-week intervention of 1-hour-long PHE intervals 5 days a week, at a fraction of inspired oxygen (FIO2) of 0.15, was beneficial for pulmonary ventilation, submaximal exercise, and maximum oxygen consumption ([Formula: see text]O2max), but an FIO2 of 0.12 reduced hyperemic response and antioxidative capacity. While IHT may be beneficial for increased lipid metabolism in the short term, it is unlikely to confer any additional advantage over normoxic exercise over the long term. IHT may improve vascular health and autonomic balance.
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Affiliation(s)
- Catherine A Lizamore
- Department of Tourism, Sport and Society, Lincoln University , Lincoln, New Zealand
| | - Michael J Hamlin
- Department of Tourism, Sport and Society, Lincoln University , Lincoln, New Zealand
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Suzuki J. Short-duration intermittent hypoxia enhances endurance capacity by improving muscle fatty acid metabolism in mice. Physiol Rep 2016; 4:4/7/e12744. [PMID: 27044851 PMCID: PMC4831319 DOI: 10.14814/phy2.12744] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2016] [Accepted: 02/29/2016] [Indexed: 12/20/2022] Open
Abstract
This study was designed to (1) investigate the effects of acute short-duration intermittent hypoxia on musclemRNAand microRNAexpression levels; and (2) clarify the mechanisms by which short-duration intermittent hypoxia improves endurance capacity. Experiment-1: Male mice were subjected to either acute 1-h hypoxia (12% O2), acute short-duration intermittent hypoxia (12% O2for 15 min, room air for 10 min, 4 times, Int-Hypo), or acute endurance exercise (Ex). The expression of vascular endothelial growth factor-AmRNAwas significantly greater than the control at 0 h post Ex and 6 h post Int-Hypo in the deep red region of the gastrocnemius muscle. miR-16 expression levels were significantly lower at 6 and 10 h post Int-Hypo. Peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PGC-1α)mRNAlevels were significantly greater than the control at 3 h post Ex and 6 h post Int-Hypo. miR-23a expression levels were lower than the control at 6-24 h post Int-Hypo. Experiment-2: Mice were subjected to normoxic exercise training with or without intermittent hypoxia for 3 weeks. Increases in maximal exercise capacity were significantly greater by training with short-duration intermittent hypoxia (IntTr) than without hypoxia. Both 3-Hydroxyacyl-CoA-dehydrogenase and total carnitine palmitoyl transferase activities were significantly enhanced in IntTr. Peroxisome proliferator-activated receptor delta andPGC-1α mRNAlevels were both significantly greater in IntTr than in the sedentary controls. These results suggest that exercise training under normoxic conditions with exposure to short-duration intermittent hypoxia represents a beneficial strategy for increasing endurance performance by enhancing fatty acid metabolism in skeletal muscle.
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Affiliation(s)
- Junichi Suzuki
- Laboratory of Exercise Physiology, Health and Sports Sciences, Course of Sports Education, Department of Education, Hokkaido University of Education, Midorigaoka, Iwamizawa, Hokkaido, 068-8642, Japan
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13
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Taralov ZZ, Terziyski KV, Kostianev SS. Heart Rate Variability as a Method for Assessment of the Autonomic Nervous System and the Adaptations to Different Physiological and Pathological Conditions. Folia Med (Plovdiv) 2016; 57:173-80. [PMID: 27180343 DOI: 10.1515/folmed-2015-0036] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2015] [Accepted: 01/07/2016] [Indexed: 01/08/2023] Open
Abstract
The autonomic nervous system controls the smooth muscles of the internal organs, the cardiovascular system and the secretory function of the glands and plays a major role in the processes of adaptation. Heart rate variability is a non-invasive and easily applicable method for the assessment of its activity. The following review describes the origin, parameters and characteristics of this method and its potential for evaluation of the changes of the autonomic nervous system activity in different physiological and pathological conditions such as exogenous hypoxia, physical exercise and sleep. The application of heart rate variability in daily clinical practice would be beneficial for the diagnostics, the outcome prognosis and the assessment of the effect of treatment in various diseases.
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Affiliation(s)
- Zdravko Z Taralov
- Department of Pathophysiology, Faculty of Medicine, Medical University, Plovdiv, Bulgaria
| | - Kiril V Terziyski
- Department of Pathophysiology, Faculty of Medicine, Medical University, Plovdiv, Bulgaria
| | - Stefan S Kostianev
- Department of Pathophysiology, Faculty of Medicine, Medical University, Plovdiv, Bulgaria
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Millet GP, Debevec T, Brocherie F, Malatesta D, Girard O. Therapeutic Use of Exercising in Hypoxia: Promises and Limitations. Front Physiol 2016; 7:224. [PMID: 27375500 PMCID: PMC4902009 DOI: 10.3389/fphys.2016.00224] [Citation(s) in RCA: 87] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2016] [Accepted: 05/30/2016] [Indexed: 01/03/2023] Open
Affiliation(s)
- Gregoire P. Millet
- Institute of Sport Sciences of the University of Lausanne (ISSUL)Lausanne, Switzerland
| | - Tadej Debevec
- Department of Automation, Biocybernetics and Robotics, Jožef Stefan InstituteLjubljana, Slovenia
| | - Franck Brocherie
- Institute of Sport Sciences of the University of Lausanne (ISSUL)Lausanne, Switzerland
| | - Davide Malatesta
- Institute of Sport Sciences of the University of Lausanne (ISSUL)Lausanne, Switzerland
| | - Olivier Girard
- Institute of Sport Sciences of the University of Lausanne (ISSUL)Lausanne, Switzerland
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Flaherty G, O'Connor R, Johnston N. Altitude training for elite endurance athletes: A review for the travel medicine practitioner. Travel Med Infect Dis 2016; 14:200-11. [PMID: 27040934 DOI: 10.1016/j.tmaid.2016.03.015] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2015] [Revised: 03/22/2016] [Accepted: 03/23/2016] [Indexed: 11/30/2022]
Abstract
High altitude training is regarded as an integral component of modern athletic preparation, especially for endurance sports such as middle and long distance running. It has rapidly achieved popularity among elite endurance athletes and their coaches. Increased hypoxic stress at altitude facilitates key physiological adaptations within the athlete, which in turn may lead to improvements in sea-level athletic performance. Despite much research in this area to date, the exact mechanisms which underlie such improvements remain to be fully elucidated. This review describes the current understanding of physiological adaptation to high altitude training and its implications for athletic performance. It also discusses the rationale and main effects of different training models currently employed to maximise performance. Athletes who travel to altitude for training purposes are at risk of suffering the detrimental effects of altitude. Altitude illness, weight loss, immune suppression and sleep disturbance may serve to limit athletic performance. This review provides an overview of potential problems which an athlete may experience at altitude, and offers specific training recommendations so that these detrimental effects are minimised.
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Affiliation(s)
- Gerard Flaherty
- School of Medicine, National University of Ireland, Galway, Ireland; School of Medicine, International Medical University, Kuala Lumpur, Malaysia.
| | - Rory O'Connor
- School of Biomedical Science, National University of Ireland, Galway, Ireland.
| | - Niall Johnston
- School of Medicine, National University of Ireland, Galway, Ireland.
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Taralov Z, Terziyski K, Dimov P, Marinov B, Tarvainen MP, Perini R, Kostianev S. Assessment of the acute impact of normobaric hypoxia as a part of an intermittent hypoxic training on heart rate variability. COR ET VASA 2015. [DOI: 10.1016/j.crvasa.2015.05.010] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Abstract
Many sports incorporate training at altitude as a key component of their athlete training plan. Furthermore, many sports are required to compete at high altitude venues. Exercise at high altitude provides unique challenges to the athlete and to the sport medicine clinician working with these athletes. These challenges include altitude illness, alterations in training intensity and performance, nutritional and hydration difficulties, and challenges related to the austerity of the environment. Furthermore, many of the strategies that are typically utilized by visitors to altitude may have implications from an anti-doping point of view.This position statement was commissioned and approved by the Canadian Academy of Sport and Exercise Medicine. The purpose of this statement was to provide an evidence-based, best practices summary to assist clinicians with the preparation and management of athletes and individuals travelling to altitude for both competition and training.
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Sanchis-Gomar F, Pareja-Galeano H, Brioche T, Martinez-Bello V, Lippi G. Altitude exposure in sports: the Athlete Biological Passport standpoint. Drug Test Anal 2013; 6:190-3. [DOI: 10.1002/dta.1539] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2013] [Revised: 08/14/2013] [Accepted: 08/14/2013] [Indexed: 11/07/2022]
Affiliation(s)
- Fabian Sanchis-Gomar
- Faculty of Medicine, Department of Physiology; University of Valencia; Spain
- Fundación Investigación Hospital Clínico Universitario/INCLIVA; Spain
| | - Helios Pareja-Galeano
- Faculty of Medicine, Department of Physiology; University of Valencia; Spain
- Fundación Investigación Hospital Clínico Universitario/INCLIVA; Spain
| | - Thomas Brioche
- Faculty of Medicine, Department of Physiology; University of Valencia; Spain
- Fundación Investigación Hospital Clínico Universitario/INCLIVA; Spain
- Laboratory M2S (Movement, Sport and Health Sciences); UFR-APS Rennes Cedex France
| | - Vladimir Martinez-Bello
- Faculty of Teaching, Department of Teaching of Musical, Visual and Corporal Expression; University of Valencia; Spain
| | - Giuseppe Lippi
- Clinical Chemistry and Hematology Laboratory, Department of Pathology and Laboratory Medicine; Academic Hospital of Parma; Italy
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Sanchis-Gomar F, Viña J, Lippi G. Intermittent hypobaric hypoxia applicability in myocardial infarction prevention and recovery. J Cell Mol Med 2012; 16:1150-4. [PMID: 22151473 PMCID: PMC4365893 DOI: 10.1111/j.1582-4934.2011.01508.x] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Abstract
Intermittent hypobaric hypoxia (IHH) has been the focus of important research in cardioprotection, and it has been associated with several mechanisms. Intermittent hypobaric hypoxia inhibits prolyl hydroxylases (PHD) activity, increasing the stabilization of hypoxia-inducible factor-1 (HIF-1) and activating crucial adaptative genes. It has been hence suggested that IHH might be a simple intervention, which may offer a thoughtful benefits to patients with acute myocardial infarction and no complications. Nevertheless, several doubts exist as to whether IHH is a really safe technique, with little to no complications in post-myocardial infarction patients. Intermittent hypobaric hypoxia might produce instead unfavourable changes such as impairment of vascular hemodynamics and hypertensive response, increased risk of hemoconcentration and thrombosis, cardiac rhythm perturbations, coronary artery disease and heart failure, insulin resistance, steatohepatitis and even high-altitude pulmonary oedema in susceptible or nonacclimatized patients. Although intermittent and chronic exposures seem effective in cardioprotection, IHH safety issues have been mostly overlooked, so that assorted concerns should be raised about the opportunity to use IHH in the post-myocardial infarction period. Several IHH protocols used in some studies were also aggressive, which would hamper their widespread introduction within the clinical practice. As such, further research is needed before IHH can be widely advocated in myocardial infarction prevention and recovery.
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Affiliation(s)
- Fabian Sanchis-Gomar
- Faculty of Medicine, Department of Physiology, University of Valencia, Valencia, Spain.
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Debevec T, Mekjavic IB. Short intermittent hypoxic exposures augment ventilation but do not alter regional cerebral and muscle oxygenation during hypoxic exercise. Respir Physiol Neurobiol 2012; 181:132-42. [DOI: 10.1016/j.resp.2012.02.008] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2011] [Revised: 02/20/2012] [Accepted: 02/23/2012] [Indexed: 11/25/2022]
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Sanchis-Gomar F, Martinez-Bello VE, Gomez-Cabrera MC, Viña J. Current limitations of the Athlete's Biological Passport use in sports. Clin Chem Lab Med 2011; 49:1413-5. [PMID: 21619474 DOI: 10.1515/cclm.2011.609] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
The Athletes Biological Passport (ABP) has received both criticisms and support during this year. In a recent issue of The Lancet, Michael Wozny considered that the use of the ABP makes it more difficult to take banned substances and that it was successfully used against the Italian elite cyclist Franco Pellizotti. After that, Italy's anti-doping tribunal considered that there was not enough evidence to prove manipulation of his own blood profile in Pellizotti's case. However, the UCI appealed to the Court of Arbitration for Sport (CAS) that sanctioned Pellizotti with a suspension of 2 years. Since its implementation, some problems have emerged. From 2010 to date, a large number of reports regarding the stability of the blood variables used to determine the ABP have been published, showing mixed results. This study considers that there is a risk of misinterpreting the physiological variations of the hematological parameters determined by the anti-doping authorities in the ABP. The analytical variability due to exercise training and competitions and/or to different metabolic energy demands, hypoxia treatments, etc. could lead to an increase in false-positives when using the ABP with the dramatic consequences that they might cause in major sports events like the forthcoming London Olympic Games. Moreover, the ABP characteristics, procedures, thresholds, or individual determination of reference ranges, abnormal out-comes, strikes, "how the profile differs from what is expected in clean athletes" should be clearly stated and explained in a new public technical document to avoid misunderstandings and to promote transparency.
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Affiliation(s)
- Fabian Sanchis-Gomar
- Department of Physiology, Faculty of Medicine, University of Valencia, Fundacion Investigacion Hospital Clinico Universitario/INCLIVA, Spain
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Taylor L, Midgley AW, Chrismas B, Hilman AR, Madden LA, Vince RV, McNaughton LR. Daily hypoxia increases basal monocyte HSP72 expression in healthy human subjects. Amino Acids 2010; 40:393-401. [PMID: 20552383 DOI: 10.1007/s00726-010-0644-x] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2010] [Accepted: 05/27/2010] [Indexed: 01/19/2023]
Abstract
Heat shock protein 72 (HSP72) performs vital roles within the body at rest and during periods of stress. In vitro, research demonstrates HSP72 induction in response to hypoxia. Recently, in vivo, an acute hypoxic exposure (75 min at 2,980 m) was sufficient to induce significant increases in monocyte expressed HSP72 (mHSP72) and a marker of oxidative stress in healthy human subjects. The purpose of the current study was to identify the impact of 10 consecutive days of hypoxic exposures (75 min at 2,980 m) on mHSP72 and erythropoietin (EPO) expression, markers of oxidative stress, and maximal oxygen consumption in graded incremental aerobic exercise. Eight male subjects were exposed to daily normobaric hypoxic exposures for 75 min at 2,980 m for 10 consecutive days, commencing and ceasing at 0930 and 1045, respectively. This stressor was sufficient to induce significant increases in mHSP72, which was significantly elevated from day 2 of the hypoxic exposures until 48 h post-final exposure. Notably, this increase had an initial rapid (30% day on day compared to baseline) and final slow phase (16% day on day compared to baseline) of expression. The authors postulate that 7-day hypoxic exposure in this manner would be sufficient to induce near maximum hypoxia-mediated basal mHSP72 expression. Elevated levels of mHSP72 are associated with acquired thermotolerance and provide cross tolerance to non-related stressors in vivo, the protocol used here may provide a useful tool for elevating mHSP72 in vivo. Aside from these major findings, significant transient daily elevations were seen in a marker of oxidative stress, alongside sustained increases in EPO expression. However, no physiologically significant changes were seen in maximal oxygen consumption or time to exhaustion.
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Affiliation(s)
- Lee Taylor
- Department of Sport, Health and Exercise Science, University of Hull, Hull, HU6 7RX, UK
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Hamlin MJ, Marshall HC, Hellemans J, Ainslie PN. Effect of intermittent hypoxia on muscle and cerebral oxygenation during a 20-km time trial in elite athletes: a preliminary report. Appl Physiol Nutr Metab 2010; 35:548-59. [DOI: 10.1139/h10-044] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
The effects of intermittent hypoxic exposure (IHE) on cerebral and muscle oxygenation, arterial oxygen saturation (SaO2), and respiratory gas exchange during a 20-km cycle time trial (20TT) were examined (n = 9) in a placebo-controlled randomized design. IHE (7:3 min hypoxia to normoxia) involved 90-min sessions for 10 days, with SaO2 clamped at ∼80%. Prior to, and 2 days after the intervention, a 20TT was performed. During the final minute of the 20TT, in the IHE group only, muscle oxyhemoglobin (oxy-Hb) was elevated (mean ± 95% confidence interval 1.3 ± 1.2 ΔµM, p = 0.04), whereas cerebral oxy-Hb was reduced (–1.9% ± 1.0%, p < 0.01) post intervention compared with baseline. The 20TT performance was unchanged between groups (p = 0.7). In the IHE group, SaO2 was higher (1.0 ± 0.7Δ%, p = 0.006) and end-tidal PCO2 was lower (–1.2 ± 0.1 mm Hg, p = 0.01) during the final stage of the 20TT post intervention compared with baseline. In summary, reductions in muscle oxy-Hb and systemic SaO2 occurring at exercise intensities close to maximal at the end of a 20TT were offset by IHE, although this was not translated into improved performance.
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Affiliation(s)
- Michael J. Hamlin
- Department of Social Science, Parks, Recreation, Tourism, and Sport, Environment Society and Design Division, P.O. Box 84, Lincoln University, Canterbury 7647, New Zealand
- New Zealand Academy of Sport, Dunedin, New Zealand
- Department of Human Kinetics, University of British Columbia Okanagan, Kelowna, BC V6T 1Z1, Canada
| | - Helen C. Marshall
- Department of Social Science, Parks, Recreation, Tourism, and Sport, Environment Society and Design Division, P.O. Box 84, Lincoln University, Canterbury 7647, New Zealand
- New Zealand Academy of Sport, Dunedin, New Zealand
- Department of Human Kinetics, University of British Columbia Okanagan, Kelowna, BC V6T 1Z1, Canada
| | - John Hellemans
- Department of Social Science, Parks, Recreation, Tourism, and Sport, Environment Society and Design Division, P.O. Box 84, Lincoln University, Canterbury 7647, New Zealand
- New Zealand Academy of Sport, Dunedin, New Zealand
- Department of Human Kinetics, University of British Columbia Okanagan, Kelowna, BC V6T 1Z1, Canada
| | - Philip N. Ainslie
- Department of Social Science, Parks, Recreation, Tourism, and Sport, Environment Society and Design Division, P.O. Box 84, Lincoln University, Canterbury 7647, New Zealand
- New Zealand Academy of Sport, Dunedin, New Zealand
- Department of Human Kinetics, University of British Columbia Okanagan, Kelowna, BC V6T 1Z1, Canada
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Millet GP. The Authorʼs Reply. Sports Med 2010. [DOI: 10.2165/11535140-000000000-00000] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
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25
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Gore CJ, McSharry PE, Hewitt AJ, Saunders PU. Preparation for football competition at moderate to high altitude. Scand J Med Sci Sports 2008; 18 Suppl 1:85-95. [DOI: 10.1111/j.1600-0838.2008.00836.x] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
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