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Degens H, Venckunas T, Wüst RC. A modelling approach to disentangle the factors limiting muscle oxygenation in smokers. Eur J Appl Physiol 2024; 124:457-466. [PMID: 37543954 PMCID: PMC10858155 DOI: 10.1007/s00421-023-05289-y] [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: 04/24/2023] [Accepted: 07/10/2023] [Indexed: 08/08/2023]
Abstract
Cigarette smoking is associated with a lower exercise capacity and lower muscle fatigue resistance. This is at least partly attributable to carboxyhaemoglobin (HbCO) in the blood that via reduction in the oxygen-carrying capacity, and the left-shift of the Hb-dissociation curve would reduce tissue oxygenation. On the other hand, a reduced oxygen uptake due to mitochondrial dysfunction would result in improved oxygenation. We used previously collected capillarisation, myoglobin and estimated cellular maximal muscle oxygen consumption data derived from succinate dehydrogenase-stained sections from the vastus lateralis muscle from six smokers and five non-smokers. These data were fed into an expanded Krogh tissue oxygenation model to assess whether an impaired muscle fatigue resistance in smokers is primarily due to HbCO or impaired mitochondrial respiration. The model showed that in smokers with 6% and 20% HbCO (causing a left-shift of the Hb-dissociation curve) average muscle oxygenation was reduced by 1.9% and 7.2%, respectively. Muscle oxygenation was increased by 13.3% when maximal mitochondrial respiration was reduced by 29%. A combination of a 29% reduction in maximal mitochondrial respiration and 20% HbCO led to no significant difference in muscle oxygenation from that in non-smokers. This indicates that while HbCO may explain the reduced exercise capacity after just one smoking session, in chronic smokers impaired mitochondrial respiration appears more important in reducing oxygen extraction and exercise capacity with only a small contribution of the left-shift of the Hb-dissociation curve.
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Affiliation(s)
- Hans Degens
- Department of Life Sciences, Research Centre for Musculoskeletal Science and Sports Medicine, Manchester Metropolitan University, John Dalton Building, Chester Street, Manchester, M1 5GD, UK.
- Lithuanian Sports University, Kaunas, Lithuania.
| | - Tomas Venckunas
- Department of Life Sciences, Research Centre for Musculoskeletal Science and Sports Medicine, Manchester Metropolitan University, John Dalton Building, Chester Street, Manchester, M1 5GD, UK
| | - Rob Cl Wüst
- Laboratory of Myology, Department of Human Movement Sciences, Faculty of Behavioural and Movement Sciences, Amsterdam Movement Sciences, Vrije Universiteit Amsterdam, Amsterdam, The Netherlands
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Tan JY, Anderson DE, Rathore AP, O’Neill A, Mantri CK, Saron WA, Lee CQ, Cui CW, Kang AE, Foo R, Kalimuddin S, Low JG, Ho L, Tambyah P, Burke TW, Woods CW, Chan KR, Karhausen J, St. John AL. Mast cell activation in lungs during SARS-CoV-2 infection associated with lung pathology and severe COVID-19. J Clin Invest 2023; 133:e149834. [PMID: 37561585 PMCID: PMC10541193 DOI: 10.1172/jci149834] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2021] [Accepted: 08/08/2023] [Indexed: 08/12/2023] Open
Abstract
Lung inflammation is a hallmark of Coronavirus disease 2019 (COVID-19) in patients who are severely ill, and the pathophysiology of disease is thought to be immune mediated. Mast cells (MCs) are polyfunctional immune cells present in the airways, where they respond to certain viruses and allergens and often promote inflammation. We observed widespread degranulation of MCs during acute and unresolved airway inflammation in SARS-CoV-2-infected mice and nonhuman primates. Using a mouse model of MC deficiency, MC-dependent interstitial pneumonitis, hemorrhaging, and edema in the lung were observed during SARS-CoV-2 infection. In humans, transcriptional changes in patients requiring oxygen supplementation also implicated cells with a MC phenotype in severe disease. MC activation in humans was confirmed through detection of MC-specific proteases, including chymase, the levels of which were significantly correlated with disease severity and with biomarkers of vascular dysregulation. These results support the involvement of MCs in lung tissue damage during SARS-CoV-2 infection in animal models and the association of MC activation with severe COVID-19 in humans, suggesting potential strategies for intervention.
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Affiliation(s)
- Janessa Y.J. Tan
- Program in Emerging Infectious Diseases, Duke-NUS Medical School, Singapore
| | - Danielle E. Anderson
- The Peter Doherty Institute for Infection and Immunity, University of Melbourne, Melbourne, Victoria, Australia
- Victorian Infectious Diseases Reference Laboratory, Melbourne, Victoria, Australia
| | - Abhay P.S. Rathore
- Department of Pathology, Duke University Medical Center, Durham, North Carolina, USA
| | - Aled O’Neill
- Program in Emerging Infectious Diseases, Duke-NUS Medical School, Singapore
| | | | | | - Cheryl Q.E. Lee
- Duke-NUS Medical School, Program in Cardiovascular and Metabolic Disorders, Singapore
| | - Chu Wern Cui
- Duke-NUS Medical School, Program in Cardiovascular and Metabolic Disorders, Singapore
| | - Adrian E.Z. Kang
- Program in Emerging Infectious Diseases, Duke-NUS Medical School, Singapore
| | - Randy Foo
- Program in Emerging Infectious Diseases, Duke-NUS Medical School, Singapore
| | - Shirin Kalimuddin
- Program in Emerging Infectious Diseases, Duke-NUS Medical School, Singapore
- Department of Infectious Diseases, Singapore General Hospital, Singapore
| | - Jenny G. Low
- Program in Emerging Infectious Diseases, Duke-NUS Medical School, Singapore
- Department of Infectious Diseases, Singapore General Hospital, Singapore
| | - Lena Ho
- Duke-NUS Medical School, Program in Cardiovascular and Metabolic Disorders, Singapore
| | - Paul Tambyah
- Infectious Diseases Translational Research Programme, Department of Medicine, Yong Loo Lin School of Medicine, National University of Singapore, Singapore
- Division of Infectious Disease, University Medicine Cluster, National University Hospital, Singapore
| | - Thomas W. Burke
- Center for Applied Genomics and Precision Medicine, Duke University Medical Center, Durham, North Carolina, USA
| | - Christopher W. Woods
- Center for Applied Genomics and Precision Medicine, Duke University Medical Center, Durham, North Carolina, USA
- Division of Infectious Diseases, Duke University Medical Center, Durham VA Medical Center, Durham, North Carolina, USA
| | - Kuan Rong Chan
- Program in Emerging Infectious Diseases, Duke-NUS Medical School, Singapore
| | - Jörn Karhausen
- Department of Pathology, Duke University Medical Center, Durham, North Carolina, USA
- Department of Anesthesiology, Duke University Medical Center, Durham, North Carolina, USA
| | - Ashley L. St. John
- Program in Emerging Infectious Diseases, Duke-NUS Medical School, Singapore
- Department of Pathology, Duke University Medical Center, Durham, North Carolina, USA
- Department of Microbiology and Immunology, National University of Singapore, Singapore
- SingHealth Duke-NUS Global Health Institute, Singapore
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Mildenhall MJ, Maunder ED, Plews DJ, Lindinger MI, Cairns SP. Plasma Acidosis and Peak Power after a Supramaximal Trial in Elite Sprint and Endurance Cyclists: Effect of Bicarbonate. Med Sci Sports Exerc 2023; 55:932-944. [PMID: 36729629 DOI: 10.1249/mss.0000000000003104] [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: 02/03/2023]
Abstract
PURPOSE This study aimed to determine whether (i) a plasma acidosis contributes to a reduction of mechanical performance and (ii) bicarbonate supplementation blunts plasma acidosis and arterial oxygen desaturation to resist fatigue during the end spurt of a supramaximal trial in elite sprint and endurance cyclists. METHODS Elite/world-class cyclists ( n = 6 sprint, n = 6 endurance) completed two randomized, double-blind, crossover trials at 105%V̇O 2peak simulating 3 min of a 4-km individual pursuit, 90 min after ingestion of 0.3 g·kg -1 BM sodium bicarbonate (BIC) or placebo (PLA). Peak power output (PPO), optimal cadence and optimal peak torque, and fatigue were assessed using a 6-s "all-out sprint" before (PPO1) and after (PPO2) each trial. Plasma pH, bicarbonate, lactate - , K + , Na + , Ca 2+ , and arterial hemoglobin saturation (SpO 2 (%)), were measured. RESULTS Sprint cyclists exhibited a higher PPO, optimal pedal torque, and anaerobic power reserve (APR) than endurance cyclists. The trial reduced PPO (PLA) more for sprint (to 47% initial) than endurance cyclists (to 61% initial). Optimal cadence fell from ~151 to 92 rpm and cyclists with higher APR exhibited a reduced optimal peak torque. Plasma pH fell from 7.35 to 7.13 and plasma [lactate - ] increased from 1.2 to 19.6 mM (PLA), yet neither correlated with PPO loss. Sprint cyclists displayed a lesser plasma acidosis but greater fatigue than endurance cyclists. BIC increased plasma [HCO 3- ] (+6.8 mM) and plasma pH after PPO1 (+0.09) and PPO2 (+0.07) yet failed to influence mechanical performance. SpO 2 fell from 99% to 96% but was unrelated to the plasma acidosis and unaltered with BIC. CONCLUSIONS Plasma acidosis was not associated with the decline of PPO in a supramaximal trial with elite cyclists. BIC attenuated acid-base disturbances yet did not improve arterial oxygen desaturation or mechanical performance at the end-spurt stage.
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Affiliation(s)
| | - E D Maunder
- SPRINZ, School of Sport and Recreation, Faculty of Health and Environmental Sciences, Auckland University of Technology, Auckland, NEW ZEALAND
| | - Daniel J Plews
- SPRINZ, School of Sport and Recreation, Faculty of Health and Environmental Sciences, Auckland University of Technology, Auckland, NEW ZEALAND
| | - Michael I Lindinger
- Research and Development, The Nutraceutical Alliance, Burlington, Ontario, CANADA
| | - Simeon P Cairns
- SPRINZ, School of Sport and Recreation, Faculty of Health and Environmental Sciences, Auckland University of Technology, Auckland, NEW ZEALAND
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Kolb JP, Hättich A, Strahl A, Rolvien T, Hennigs JK, Barg A, Frosch KH, Hartel MJ, Schlickewei C. Does the COVID-19 personal protective equipment impair the surgeon's performance? Arch Orthop Trauma Surg 2023; 143:1989-1997. [PMID: 35306584 PMCID: PMC8934057 DOI: 10.1007/s00402-022-04416-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/16/2021] [Accepted: 12/23/2021] [Indexed: 11/30/2022]
Abstract
INTRODUCTION Despite increasing vaccination rates, new viral variants of SARS-CoV-2 (severe acute respiratory syndrome coronavirus type 2) are advancing the COVID 19 (coronavirus disease 2019) pandemic and continue to challenge the entire world. Surgical care of SARS-CoV-2 positive patients requires special protective measures. We hypothesized that "COVID-19" personal protective equipment (PPE) during surgery of SARS-CoV-2 positive or potentially positive patients would negatively affect the surgeon and thus the surgical outcome. MATERIALS AND METHODS Ten experienced trauma surgeons participated in the study. Each surgeon performed two simulated surgeries of a distal tibial fracture on a Sawbone® under standardized conditions either wearing regular PPE or special COVID-19 PPE. Baseline values at rest were acquired for heart rate, blood pressure, saturation of peripheral oxygen (SpO2), respiratory rate and capillary blood gas (CBG) analysis including capillary partial pressure of oxygen (pO2) and carbon dioxide (pCO2), followed by four different standardized tests of attentional performance (TAP). Subsequently, the surgeon performed the first surgery according to a randomly determined order, with regular or COVID-19 PPE conditions in an operation theatre. After each surgery vital signs were acquired and CBG and TAP were performed again. RESULTS In our simulated surgical procedure heart rate, respiratory rate, systolic and diastolic blood pressure did not show relevant differences. Percutaneously measured SpO2 decreased with additional layers of PPE, while CBG parameters were not affected. TAP tests showed a significant impairment of attention if PPEs were compared to the baseline, but both PPEs had similar results and no meaningful differences could be measured. CONCLUSIONS According to our results, for surgical procedures additional PPE required during COVID-19 pandemic does not relevant affect the surgeon's mental and physical performance. Surgeries under COVID-19 PPE conditions appear safe and do not increase patient risk. LEVEL OF EVIDENCE Level I.
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Affiliation(s)
- Jan P Kolb
- Department of Trauma and Orthopaedic Surgery, University Medical Center Hamburg-Eppendorf, Martinistrasse 52, 20246, Hamburg, Germany
| | - Annika Hättich
- Department of Trauma and Orthopaedic Surgery, University Medical Center Hamburg-Eppendorf, Martinistrasse 52, 20246, Hamburg, Germany
| | - André Strahl
- Department of Trauma and Orthopaedic Surgery, University Medical Center Hamburg-Eppendorf, Martinistrasse 52, 20246, Hamburg, Germany
| | - Tim Rolvien
- Department of Trauma and Orthopaedic Surgery, University Medical Center Hamburg-Eppendorf, Martinistrasse 52, 20246, Hamburg, Germany
| | - Jan K Hennigs
- Department of Pneumology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Alexej Barg
- Department of Trauma and Orthopaedic Surgery, University Medical Center Hamburg-Eppendorf, Martinistrasse 52, 20246, Hamburg, Germany
- Department of Trauma Surgery, Orthopaedics and Sports Traumatology, BG Hospital Hamburg, Hamburg, Germany
- Department of Orthopaedics, University of Utah, Salt Lake City, USA
| | - Karl-Heinz Frosch
- Department of Trauma and Orthopaedic Surgery, University Medical Center Hamburg-Eppendorf, Martinistrasse 52, 20246, Hamburg, Germany
- Department of Trauma Surgery, Orthopaedics and Sports Traumatology, BG Hospital Hamburg, Hamburg, Germany
| | - Maximilian J Hartel
- Department of Trauma and Orthopaedic Surgery, University Medical Center Hamburg-Eppendorf, Martinistrasse 52, 20246, Hamburg, Germany
- Department of Trauma Surgery, Orthopaedics and Sports Traumatology, BG Hospital Hamburg, Hamburg, Germany
| | - Carsten Schlickewei
- Department of Trauma and Orthopaedic Surgery, University Medical Center Hamburg-Eppendorf, Martinistrasse 52, 20246, Hamburg, Germany.
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Cristina-Souza G, Santos PS, Santos-Mariano AC, Coelho DB, Rodacki A, DE-Oliveira FR, Bishop DJ, Bertuzzi R, Lima-Silva AE. Caffeine Increases Endurance Performance via Changes in Neural and Muscular Determinants of Performance Fatigability. Med Sci Sports Exerc 2022; 54:1591-1603. [PMID: 35969166 DOI: 10.1249/mss.0000000000002944] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
PURPOSE In the present study, we tested the hypothesis that caffeine would increase endurance performance via attenuation of neural and muscular determinants of performance fatigability during high-intensity, whole-body exercise. METHODS Ten healthy males cycled until exhaustion (89% ± 2% of V̇O2max) after the ingestion of caffeine or placebo. During another four visits, the same exercise was performed after either caffeine or placebo ingestion but with exercise discontinued after completing either 50% or 75% of the duration of placebo trial. An additional trial with caffeine ingestion was also performed with interruption at the placebo time to exhaustion (isotime). Performance fatigability was measured via changes in maximal voluntary contraction, whereas neural and muscular determinants of performance fatigability were quantified via preexercise to postexercise decrease in quadriceps voluntary activation (VA) and potentiated twitch force, respectively. RESULTS Compared with the placebo, caffeine increased time to exhaustion (+14.4 ± 1.6%, P = 0.017, 314.4 ± 47.9 vs 354.9 ± 40.8 s). Caffeine did not change the rate of decline in maximal voluntary contraction (P = 0.209), but caffeine reduced the twitch force decline at isotime when stimulating at single twitch (-58.6 ± 22.4 vs -45.7 ± 21.9%, P = 0.014) and paired 10 Hz electrical stimuli (-37.3 ± 13.2 vs -28.2 ± 12.9%, P = 0.025), and reduced the amplitude of electromyography signal during cycling at isotime (P = 0.034). The decline in VA throughout the trial was lower (P = 0.004) with caffeine (-0.5 ± 4.2%) than with placebo (-5.8 ± 8.5%). Caffeine also maintained peripheral oxygen saturation at higher levels (95.0 ± 1.9%) than placebo (92.0 ± 6.2%, P = 0.016). CONCLUSIONS Caffeine ingestion improves performance during high-intensity, whole-body exercise via attenuation of exercise-induced reduction in VA and contractile function.
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Affiliation(s)
| | | | | | | | - Andre Rodacki
- Department of Physical Education, Federal University of Paraná, Paraná, BRAZIL
| | | | - David J Bishop
- Institute for Health and Sport, Victoria University, Melbourne, AUSTRALIA
| | - Romulo Bertuzzi
- Endurance Performance Research Group (GEDAE-USP), University of São Paulo, São Paulo, BRAZIL
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Pulmonary Capacity, Blood Composition and Metabolism among Coal Mine Workers in High- and Low-Altitude Aboveground and Underground Workplaces. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2022; 19:ijerph19148295. [PMID: 35886146 PMCID: PMC9318192 DOI: 10.3390/ijerph19148295] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 06/01/2022] [Revised: 06/27/2022] [Accepted: 06/28/2022] [Indexed: 11/25/2022]
Abstract
(1) Background: While previous studies revealed how underground mining might adversely affect the cardiopulmonary functions of workers, this study further investigated the differences between under- and aboveground mining at both high and low altitudes, which has received little attention in the literature. (2) Methods: Seventy-one healthy male coal mine workers were recruited, who had worked at least 5 years at the mining sites located above the ground at high (>3900 m; n = 19) and low (<120 m; n = 16) altitudes as well as under the ground at high (n = 20) and low (n = 16) altitudes. Participants’ heart rates, pulmonary functions, total energy expenditure and metabolism were measured over a 5-consecutive-day session at health clinics. (3) Results: Combining the results for both above- and underground locations, workers at high-altitude mining sites had significantly higher peak heart rate (HR), minimum average HR and training impulse as well as energy expenditure due to all substances and due to fat than those at low-altitude sites. They also had significantly higher uric acid, total cholesterol, creatine kinase and N-osteocalcin in their blood samples than the workers at low-altitude mining sites. At underground worksites, the participants working at high-altitude had a significantly higher average respiratory rate than those at low-altitude regions. (4) Conclusion: In addition to underground mining, attention should be paid to high-altitude mining as working under a hypoxia condition at such altitude likely presents physiological challenges.
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Elsisi HFEM, Aneis YM, El Refaye GE, Ghareeb HO. Blood oxygenation response to aerobic exercise combined with breathing exercises in pregnant women: a randomized controlled trial. BULLETIN OF FACULTY OF PHYSICAL THERAPY 2022. [DOI: 10.1186/s43161-022-00073-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
Abstract
Background
There are many physiological changes occur during pregnancy that affect oxygenation of the pregnant women. It was considered that aerobic and breathing exercises are safe for the mother and the fetus especially moderate intensity exercise during pregnancy.
Objective
This study was designed to investigate the blood oxygenation response to aerobic exercise combined with breathing exercises in pregnant women.
Methodology
Forty pregnant women were selected from obstetrics and gynecology outpatient clinic at Kasr El Einy Hospital, Egypt, confidentiality was assured. They were ranged from 25 to 30 years old, with body mass index (BMI) less than 30 kg/m2 and at the beginning of 3rd trimester, this study was conducted from September 2019 to April 2020. They were assigned into two groups: group A performed aerobic exercise in a form of walking for 20 min. On the treadmill at 60–75% of the maximum heart rate (MHR) of each woman, three times per week in addition to deep breathing exercises in form of diaphragmatic and lateral costal breathing; group B who performed deep breathing exercises only in form of diaphragmatic and lateral costal breathing. The program continued for three months, three times per week. The oxygen saturation (SaO2) was measured twice time, firstly, at the beginning of 3rd trimester of pregnancy then after three months of treatment program.
Results
The results of this study revealed a statistically significant difference in the oxygen saturation in group A than in group B.
Conclusion
It could be concluded that there was significant statistical effect of aerobic exercise combined with breathing exercises on blood oxygenation in pregnant women. It improved the oxygen saturation in pregnant women.
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Hiura M, Shirai Y, Shibutani H, Funaki A, Takahashi K, Katayama Y. Estimation of Cerebral Hemodynamics and Oxygenation During Various Intensities of Rowing Exercise: An NIRS Study. Front Physiol 2022; 13:828357. [PMID: 35309081 PMCID: PMC8924415 DOI: 10.3389/fphys.2022.828357] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2021] [Accepted: 01/31/2022] [Indexed: 11/13/2022] Open
Abstract
Purpose This study aimed to investigate changes in cerebral hemodynamics and oxygenation at moderate, heavy, maximal and supramaximal intensities of rowing exercise. It also examined whether these changes reflect alterations in sensation of effort and mood. We also aimed to examine the effects of peak pulmonary oxygen consumption (V.O2peak) on cerebral oxygenation. Methods Eleven rowers, consisting out of six athletes and five recreational rowers [two female; age, 27 ± 9 years; height, 171 ± 7 cm, body mass, 67 ± 9 kg; V.O2peak, 53.5 ± 6.5 mL min–1 kg–1] rowed a 13-min session separated by 10 and 3 min, at 70 (Ex70%) and 80% of V.O2peak (Ex80%), respectively, on a rowing ergometer, followed by three sessions of 1-min supramaximal exercise (ExSp). After a warm-up at 60% of V.O2peak (ExM), seven male rowers performed a 2,000 m all-out test (Ex2000). Cardiovascular and respiratory variables were measured. Cerebral oxygenation was investigated by near-infrared time-resolved spectroscopy (TRS) to measure cerebral hemoglobin oxygen saturation (ScO2) and total hemoglobin concentration ([HbT]) in the prefrontal cortex (PFC) quantitatively. We estimated the relative changes from rest in cerebral metabolic rate for oxygen (rCMRO2) using TRS at all intensities. During Ex70% and Ex80%, ratings of perceived exertion (RPE) were monitored, and alteration of the subject’s mood was evaluated using a questionnaire of Positive-and-Negative-Affect-Schedule after Ex70% and Ex80%. Results When exercise intensity changed from Ex70% to Ex80%, the sense of effort increased while ScO2 decreased. [HbT] remained unchanged. After Ex70% and Ex80%, a negative mood state was less prominent compared to rest and was accompanied by increases in both ScO2 and [HbT]. At termination of Ex2000, ScO2 decreased by 23% compared to rest. Changes in ScO2 correlated with V.O2peak only during Ex2000 (r = −0.86; p = 0.01). rCMRO2 did not decrease at any intensities. Conclusion Our results suggest that alterations in the sense of effort are associated with oxygenation in the PFC, while positive changes in mood status are associated with cerebral perfusion and oxygen metabolism estimated by TRS. At exhaustion, the cerebral metabolic rate for oxygen is maintained despite a decrease in ScO2.
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Affiliation(s)
- Mikio Hiura
- Center for Brain and Health Sciences, Aomori University, Aomori, Japan
- *Correspondence: Mikio Hiura,
| | - Yusuke Shirai
- Department of Sport and Health Science, Tokai Gakuen University, Miyoshi, Japan
| | | | - Akio Funaki
- Faculty of Sociology, Aomori University, Aomori, Japan
| | - Katsumi Takahashi
- Faculty of Creative Engineering, Kanagawa Institute of Technology, Atsugi, Japan
| | - Yoichi Katayama
- Center for Brain and Health Sciences, Aomori University, Aomori, Japan
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A century of exercise physiology: key concepts on coupling respiratory oxygen flow to muscle energy demand during exercise. Eur J Appl Physiol 2022; 122:1317-1365. [PMID: 35217911 PMCID: PMC9132876 DOI: 10.1007/s00421-022-04901-x] [Citation(s) in RCA: 18] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2021] [Accepted: 01/25/2022] [Indexed: 12/26/2022]
Abstract
After a short historical account, and a discussion of Hill and Meyerhof’s theory of the energetics of muscular exercise, we analyse steady-state rest and exercise as the condition wherein coupling of respiration to metabolism is most perfect. The quantitative relationships show that the homeostatic equilibrium, centred around arterial pH of 7.4 and arterial carbon dioxide partial pressure of 40 mmHg, is attained when the ratio of alveolar ventilation to carbon dioxide flow (\documentclass[12pt]{minimal}
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\begin{document}$${\dot{V}}_{A}/{\dot{V}}_{R}{CO}_{2}$$\end{document}V˙A/V˙RCO2) is − 21.6. Several combinations, exploited during exercise, of pertinent respiratory variables are compatible with this equilibrium, allowing adjustment of oxygen flow to oxygen demand without its alteration. During exercise transients, the balance is broken, but the coupling of respiration to metabolism is preserved when, as during moderate exercise, the respiratory system responds faster than the metabolic pathways. At higher exercise intensities, early blood lactate accumulation suggests that the coupling of respiration to metabolism is transiently broken, to be re-established when, at steady state, blood lactate stabilizes at higher levels than resting. In the severe exercise domain, coupling cannot be re-established, so that anaerobic lactic metabolism also contributes to sustain energy demand, lactate concentration goes up and arterial pH falls continuously. The \documentclass[12pt]{minimal}
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\begin{document}$${\dot{V}}_{A}/{\dot{V}}_{R}{CO}_{2}$$\end{document}V˙A/V˙RCO2 decreases below − 21.6, because of ensuing hyperventilation, while lactate keeps being accumulated, so that exercise is rapidly interrupted. The most extreme rupture of the homeostatic equilibrium occurs during breath-holding, because oxygen flow from ambient air to mitochondria is interrupted. No coupling at all is possible between respiration and metabolism in this case.
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Stadheim HK, Stensrud T, Brage S, Jensen J. Caffeine Increases Exercise Performance, Maximal Oxygen Uptake, and Oxygen Deficit in Elite Male Endurance Athletes. Med Sci Sports Exerc 2021; 53:2264-2273. [PMID: 34033621 DOI: 10.1249/mss.0000000000002704] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
PURPOSE The aims of the present study were to test the hypothesis that caffeine increases maximal oxygen uptake (V˙O2max) and to characterize the physiological mechanisms underpinning improved high-intensity endurance capacity. METHODS Twenty-three elite endurance-trained male athletes were tested twice with and twice without caffeine (four tests) in a randomized, double-blinded, and placebo-controlled study with crossover design. Caffeine (4.5 mg·kg-1) or placebo was consumed 45 min before standardized warm-up. Time to exhaustion during an incremental test (running 10.5° incline, start speed 10.0 km·h-1, and 0.5 km·h-1 increase in speed every 30 s) determined performance. Oxygen uptake was measured continuously to determine V˙O2max and O2 deficit was calculated. RESULTS Caffeine increased time to exhaustion from 355 ± 41 to 375 ± 41 s (Δ19.4 ± 16.5 s; P < 0.001). Importantly, caffeine increased V˙O2max from 75.8 ± 5.6 to 76.7 ± 6.0 mL·kg-1·min-1 (Δ 0.9 ± 1.7 mL·kg-1·min-1; P < 0.003). Caffeine increased maximal heart rate (HRpeak) and ventilation (VEpeak). Caffeine increased O2 deficit from 63.1 ± 18.2 to 69.5 ± 17.5 mL·kg-1 (P < 0.02) and blood lactate compared with placebo. The increase in time to exhaustion after caffeine ingestion was reduced to 11.7 s after adjustment for the increase in V˙O2max. Caffeine did not significantly increase V˙O2max after adjustment for VEpeak and HRpeak. Adjustment for O2 deficit and lactate explained 6.2 s of the caffeine-induced increase in time to exhaustion. The increase in V˙O2max, VE, HR, O2 deficit, and lactate explained 63% of the increased performance after caffeine intake. CONCLUSION Caffeine increased V˙O2max in elite athletes, which contributed to improvement in high-intensity endurance performance. Increases in O2 deficit and lactate also contributed to the caffeine-induced improvement in endurance performance.
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Affiliation(s)
- Hans Kristian Stadheim
- Department of Physical Performance, Norwegian School of Sport Sciences, Ullevål Stadion, NORWAY
| | - Trine Stensrud
- Department of Physical Performance, Norwegian School of Sport Sciences, Ullevål Stadion, NORWAY
| | - Søren Brage
- MRC Epidemiology Unit, University of Cambridge School of Clinical Medicine, Institute of Metabolic Sciences, Cambridge Biomedical Campus, England, UNITED KINGDOM
| | - Jørgen Jensen
- Department of Physical Performance, Norwegian School of Sport Sciences, Ullevål Stadion, NORWAY
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Lopez-Pascual A, Trayhurn P, Martínez JA, González-Muniesa P. Oxygen in Metabolic Dysfunction and Its Therapeutic Relevance. Antioxid Redox Signal 2021; 35:642-687. [PMID: 34036800 DOI: 10.1089/ars.2019.7901] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Significance: In recent years, a number of studies have shown altered oxygen partial pressure at a tissue level in metabolic disorders, and some researchers have considered oxygen to be a (macro) nutrient. Oxygen availability may be compromised in obesity and several other metabolism-related pathological conditions, including sleep apnea-hypopnea syndrome, the metabolic syndrome (which is a set of conditions), type 2 diabetes, cardiovascular disease, and cancer. Recent Advances: Strategies designed to reduce adiposity and its accompanying disorders have been mainly centered on nutritional interventions and physical activity programs. However, novel therapies are needed since these approaches have not been sufficient to counteract the worldwide increasing rates of metabolic disorders. In this regard, intermittent hypoxia training and hyperoxia could be potential treatments through oxygen-related adaptations. Moreover, living at a high altitude may have a protective effect against the development of abnormal metabolic conditions. In addition, oxygen delivery systems may be of therapeutic value for supplying the tissue-specific oxygen requirements. Critical Issues: Precise in vivo methods to measure oxygenation are vital to disentangle some of the controversies related to this research area. Further, it is evident that there is a growing need for novel in vitro models to study the potential pathways involved in metabolic dysfunction to find appropriate therapeutic targets. Future Directions: Based on the existing evidence, it is suggested that oxygen availability has a key role in obesity and its related comorbidities. Oxygen should be considered in relation to potential therapeutic strategies in the treatment and prevention of metabolic disorders. Antioxid. Redox Signal. 35, 642-687.
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Affiliation(s)
- Amaya Lopez-Pascual
- Department of Nutrition, Food Science and Physiology, School of Pharmacy and Nutrition, Centre for Nutrition Research, University of Navarra, Pamplona, Spain.,Neuroendocrine Cell Biology, Lund University Diabetes Centre, Lund University, Malmö, Sweden
| | - Paul Trayhurn
- Obesity Biology Unit, University of Liverpool, Liverpool, United Kingdom.,Clore Laboratory, The University of Buckingham, Buckingham, United Kingdom
| | - J Alfredo Martínez
- Department of Nutrition, Food Science and Physiology, School of Pharmacy and Nutrition, Centre for Nutrition Research, University of Navarra, Pamplona, Spain.,IdiSNA, Navarra Institute for Health Research, Pamplona, Spain.,CIBERobn Physiopathology of Obesity and Nutrition, Centre of Biomedical Research Network, ISCIII, Madrid, Spain.,Precision Nutrition and Cardiometabolic Health, IMDEA Food, Madrid Institute for Advanced Studies, Madrid, Spain
| | - Pedro González-Muniesa
- Department of Nutrition, Food Science and Physiology, School of Pharmacy and Nutrition, Centre for Nutrition Research, University of Navarra, Pamplona, Spain.,IdiSNA, Navarra Institute for Health Research, Pamplona, Spain.,CIBERobn Physiopathology of Obesity and Nutrition, Centre of Biomedical Research Network, ISCIII, Madrid, Spain
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12
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Tan J, Anderson DE, Rathore APS, O'Neill A, Mantri CK, Saron WAA, Lee C, Cui CW, Kang AEZ, Foo R, Kalimuddin S, Low JG, Ho L, Tambyah P, Burke TW, Woods CW, Chan KR, Karhausen J, John ALS. Signatures of mast cell activation are associated with severe COVID-19. MEDRXIV : THE PREPRINT SERVER FOR HEALTH SCIENCES 2021. [PMID: 34100020 DOI: 10.1101/2021.05.31.21255594] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Lung inflammation is a hallmark of Coronavirus disease 2019 (COVID-19) in severely ill patients and the pathophysiology of disease is thought to be immune-mediated. Mast cells (MCs) are polyfunctional immune cells present in the airways, where they respond to certain viruses and allergens, often promoting inflammation. We observed widespread degranulation of MCs during acute and unresolved airway inflammation in SARS-CoV-2-infected mice and non-human primates. In humans, transcriptional changes in patients requiring oxygen supplementation also implicated cells with a MC phenotype. MC activation in humans was confirmed, through detection of the MC-specific protease, chymase, levels of which were significantly correlated with disease severity. These results support the association of MC activation with severe COVID-19, suggesting potential strategies for intervention.
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13
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Petek BJ, Gustus SK, Wasfy MM. Cardiopulmonary Exercise Testing in Athletes: Expect the Unexpected. CURRENT TREATMENT OPTIONS IN CARDIOVASCULAR MEDICINE 2021; 23. [DOI: 10.1007/s11936-021-00928-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
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14
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Archiza B, Leahy MG, Kipp S, Sheel AW. An integrative approach to the pulmonary physiology of exercise: when does biological sex matter? Eur J Appl Physiol 2021; 121:2377-2391. [PMID: 33903937 DOI: 10.1007/s00421-021-04690-9] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2020] [Accepted: 04/12/2021] [Indexed: 11/30/2022]
Abstract
Historically, many studies investigating the pulmonary physiology of exercise (and biomedical research in general) were performed exclusively or predominantly with male research participants. This has led to an incomplete understanding of the pulmonary response to exercise. More recently, important sex-based differences with respect to the human respiratory system have been identified. The purpose of this review is to summarize current findings related to sex-based differences in the pulmonary physiology of exercise. To that end, we will discuss how morphological sex-based differences of the respiratory system affect the respiratory response to exercise. Moreover, we will discuss sex-based differences of the physiological integrative responses to exercise, and how all these differences can influence the regulation of breathing. We end with a brief discussion of pregnancy and menopause and the accompanying ventilatory changes observed during exercise.
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Affiliation(s)
- Bruno Archiza
- School of Kinesiology, University of British Columbia, 2553 Wesbrook Mall, Vancouver, BC, V6T 0B8, Canada.
| | - Michael G Leahy
- School of Kinesiology, University of British Columbia, 2553 Wesbrook Mall, Vancouver, BC, V6T 0B8, Canada
| | - Shalaya Kipp
- School of Kinesiology, University of British Columbia, 2553 Wesbrook Mall, Vancouver, BC, V6T 0B8, Canada
| | - A William Sheel
- School of Kinesiology, University of British Columbia, 2553 Wesbrook Mall, Vancouver, BC, V6T 0B8, Canada
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15
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Durand F, Raberin A. Exercise-Induced Hypoxemia in Endurance Athletes: Consequences for Altitude Exposure. Front Sports Act Living 2021; 3:663674. [PMID: 33981992 PMCID: PMC8107360 DOI: 10.3389/fspor.2021.663674] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2021] [Accepted: 03/25/2021] [Indexed: 11/26/2022] Open
Abstract
Exercise-induced hypoxemia (EIH) is well-described in endurance-trained athletes during both maximal and submaximal exercise intensities. Despite the drop in oxygen (O2) saturation and provided that training volumes are similar, athletes who experience EIH nevertheless produce the same endurance performance in normoxia as athletes without EIH. This lack of a difference prompted trainers to consider that the phenomenon was not relevant to performance but also suggested that a specific adaptation to exercise is present in EIH athletes. Even though the causes of EIH have been extensively studied, its consequences have not been fully characterized. With the development of endurance outdoor activities and altitude/hypoxia training, athletes often train and/or compete in this stressful environment with a decrease in the partial pressure of inspired O2 (due to the drop in barometric pressure). Thus, one can reasonably hypothesize that EIH athletes can specifically adapt to hypoxemic episodes during exercise at altitude. Although our knowledge of the interactions between EIH and acute exposure to hypoxia has improved over the last 10 years, many questions have yet to be addressed. Firstly, endurance performance during acute exposure to altitude appears to be more impaired in EIH vs. non-EIH athletes but the corresponding physiological mechanisms are not fully understood. Secondly, we lack information on the consequences of EIH during chronic exposure to altitude. Here, we (i) review research on the consequences of EIH under acute hypoxic conditions, (ii) highlight unresolved questions about EIH and chronic hypoxic exposure, and (iii) suggest perspectives for improving endurance training.
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Affiliation(s)
- Fabienne Durand
- Images Espace Dev, Université de Perpignan Via Domitia, Perpignan, France
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16
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Conventional Testing Produces Submaximal Values for Oxygen Uptake in Elite Runners. Int J Sports Physiol Perform 2021; 16:1510-1515. [PMID: 33789244 DOI: 10.1123/ijspp.2020-0778] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2020] [Revised: 11/16/2020] [Accepted: 11/16/2020] [Indexed: 11/18/2022]
Abstract
PURPOSE This study aimecd to investigate whether elite athletes could reach higher values of maximal oxygen uptake (V˙O2max) during a decremental exercise test in comparison with a traditional incremental test, as recently demonstrated in trained individuals. METHODS Nine male runners (age 25.8 [5.1] y, season best 10-km time 31:19 [1:50]) performed, on different days, 3 maximal uphill (5% grade) running exercise tests in fixed order: an incremental test (INC1), a V-shape exercise test (where speed started at 0.5 km·h-1 higher than the top stage finished during INC1 and was slowly decreased during 5.5 min, when it was again increased in similar fashion to the INC tests), and a final incremental test (INC2). RESULTS V˙O2max during the V-shape exercise test was higher than during INC1 (6.3% [3.0%], P = .01), although running speed was lower (16.6 [1.7] vs 17.9 [1.6] km·h-1, P = .01). Performance was similar between INC1 and INC2, but V˙O2max during INC2 was higher than INC1 (P < .001). During the V-shape exercise test, 5 participants reached the incremental part of the test, but V˙O2 did not increase (ΔV˙O2=52 [259] mL·min-1, P = .67), despite higher running speed (approximately 1.1 km·h-1, P < .01). Heart rate, pulmonary ventilation, breathing rate, and respiratory exchange ratio measured at V˙O2max were not different between tests. CONCLUSION A decremental exercise test of sufficient intensity can produce higher V˙O2max than a traditional incremental test, even in elite athletes, and this is maintained during a subsequent incremental test.
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Raberin A, Nader E, Lopez Ayerbe J, Alfonsi G, Mucci P, Rytz CL, Pialoux V, Durand F. Pro-Oxidant/Antioxidant Balance during a Prolonged Exposure to Moderate Altitude in Athletes Exhibiting Exercise-Induced Hypoxemia at Sea-Level. Life (Basel) 2021; 11:life11030228. [PMID: 33799611 PMCID: PMC8001482 DOI: 10.3390/life11030228] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2021] [Revised: 03/05/2021] [Accepted: 03/08/2021] [Indexed: 12/16/2022] Open
Abstract
This study examined to what extent athletes exhibiting exercise-induced hypoxemia (EIH) possess an altered redox status at rest, in response to exercise at sea level (SL) and during moderate altitude exposure. EIH was defined as a fall in arterial O2 saturation of at least 4% during exercise. Nine endurance athletes with EIH and ten without (NEIH) performed a maximal incremental test under three conditions: SL, one (H1) and five (H2) days after arrival to 2400 m. Gas exchange and peripheral capillary oxygen saturation (SpO2) were continuously monitored. Blood was sampled before exercise and after exercise cessation. Advanced oxidation protein products (AOPP), catalase, ferric-reducing antioxidant power, glutathione peroxidase, superoxide dismutase (SOD) and nitric oxide metabolites (NOx) were measured in plasma by spectrophotometry. EIH athletes had higher AOPP and NOx concentrations at pre- and post-exercise stages compared to NEIH at SL, H2 but not at H1. Only the EIH group experienced increased SOD activity between pre- and post-exercise exercise at SL and H2 but not at H1. EIH athletes had exacerbated oxidative stress compared to the NEIH athletes at SL and H2. These differences were blunted at H1. Oxidative stress did not alter the EIH groups’ aerobic performance and could lead to higher minute ventilation at H2. These results suggest that higher oxidative stress response EIH athletes could be involved in improved aerobic muscle functionality and a greater ventilatory acclimatization during prolonged hypoxia.
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Affiliation(s)
- Antoine Raberin
- Laboratoire Européen Performance Santé Altitude (LEPSA), EA 4604, Université de Perpignan Via Domitia, 66120 Font Romeu, France;
- Correspondence: ; Tel.: +33-6-8217-3800
| | - Elie Nader
- Team « Vascular Biology and Red Blood Cell », Univ Lyon, Laboratoire Interuniversitaire de Biologie de la Motricité (LIBM) EA 7424, Université Claude Bernard Lyon 1, 69000 Lyon, France; (E.N.); (G.A.)
- Laboratoire d’Excellence du Globule Rouge (Labex GR-Ex), PRES Sorbonne, 75000 Paris, France
| | | | - Gauthier Alfonsi
- Team « Vascular Biology and Red Blood Cell », Univ Lyon, Laboratoire Interuniversitaire de Biologie de la Motricité (LIBM) EA 7424, Université Claude Bernard Lyon 1, 69000 Lyon, France; (E.N.); (G.A.)
| | - Patrick Mucci
- ULR 7369 - URePSSS - Unité de Recherche Pluridisciplinaire Sport Santé Société, Univ. Lille, Univ. Artois, Univ. Littoral Côte d’Opale, 59000 Lille, France;
| | - Chantal L. Rytz
- Department of Physiology and Pharmacology, Cumming School of Medicine, University of Calgary, Calgary, AL T2P 2M5, Canada;
- Libin Cardiovascular Institute of Alberta, Cumming School of Medicine, University of Calgary, Calgary, AL T2P 2M5, Canada
| | - Vincent Pialoux
- Team « Atherosclerosis, Thrombosis and Physical Activity », Laboratoire Interuniversitaire de Biologie de la Motricité (LIBM) EA7424, Univ Lyon, Université Claude Bernard Lyon 1, 69000 Lyon, France;
- Institut Universitaire de France, 75000 Paris, France
| | - Fabienne Durand
- Laboratoire Européen Performance Santé Altitude (LEPSA), EA 4604, Université de Perpignan Via Domitia, 66120 Font Romeu, France;
- IMAGES ESPACE-DEV, UMR228, Université de Perpignan Via Domitia, 66000 Perpignan, France
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18
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Skattebo Ø, Calbet JAL, Rud B, Capelli C, Hallén J. Contribution of oxygen extraction fraction to maximal oxygen uptake in healthy young men. Acta Physiol (Oxf) 2020; 230:e13486. [PMID: 32365270 PMCID: PMC7540168 DOI: 10.1111/apha.13486] [Citation(s) in RCA: 37] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2020] [Revised: 04/22/2020] [Accepted: 04/23/2020] [Indexed: 12/16/2022]
Abstract
We analysed the importance of systemic and peripheral arteriovenous O2 difference (
a-v¯O2 difference and a‐vfO2 difference, respectively) and O2 extraction fraction for maximal oxygen uptake (
V˙O2max). Fick law of diffusion and the Piiper and Scheid model were applied to investigate whether diffusion versus perfusion limitations vary with
V˙O2max. Articles (n = 17) publishing individual data (n = 154) on
V˙O2max, maximal cardiac output (
Q˙max; indicator‐dilution or the Fick method),
a-v¯O2 difference (catheters or the Fick equation) and systemic O2 extraction fraction were identified. For the peripheral responses, group‐mean data (articles: n = 27; subjects: n = 234) on leg blood flow (LBF; thermodilution), a‐vfO2 difference and O2 extraction fraction (arterial and femoral venous catheters) were obtained.
Q˙max and two‐LBF increased linearly by 4.9‐6.0 L · min–1 per 1 L · min–1 increase in
V˙O2max (R2 = .73 and R2 = .67, respectively; both P < .001). The
a-v¯O2 difference increased from 118‐168 mL · L–1 from a
V˙O2max of 2‐4.5 L · min–1 followed by a reduction (second‐order polynomial: R2 = .27). After accounting for a hypoxemia‐induced decrease in arterial O2 content with increasing
V˙O2max (R2 = .17; P < .001), systemic O2 extraction fraction increased up to ~90% (
V˙O2max: 4.5 L · min–1) with no further change (exponential decay model: R2 = .42). Likewise, leg O2 extraction fraction increased with
V˙O2max to approach a maximal value of ~90‐95% (R2 = .83). Muscle O2 diffusing capacity and the equilibration index Y increased linearly with
V˙O2max (R2 = .77 and R2 = .31, respectively; both P < .01), reflecting decreasing O2 diffusional limitations and accentuating O2 delivery limitations. In conclusion, although O2 delivery is the main limiting factor to
V˙O2max, enhanced O2 extraction fraction (≥90%) contributes to the remarkably high
V˙O2max in endurance‐trained individuals.
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Affiliation(s)
- Øyvind Skattebo
- Department of Physical Performance Norwegian School of Sport Sciences Oslo Norway
| | - Jose A. L. Calbet
- Department of Physical Performance Norwegian School of Sport Sciences Oslo Norway
- Department of Physical Education and Research Institute of Biomedical and Health Sciences (IUIBS) University of Las Palmas de Gran Canaria Gran Canaria Spain
| | - Bjarne Rud
- Department of Physical Performance Norwegian School of Sport Sciences Oslo Norway
| | - Carlo Capelli
- Department of Physical Performance Norwegian School of Sport Sciences Oslo Norway
- Department of Neurosciences, Biomedicine and Movement Sciences University of Verona Verona Italy
| | - Jostein Hallén
- Department of Physical Performance Norwegian School of Sport Sciences Oslo Norway
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Stensrud T, Rossvoll Ø, Mathiassen M, Melau J, Illidi C, Østgaard HN, Hisdal J, Stang J. Lung function and oxygen saturation after participation in Norseman Xtreme Triathlon. Scand J Med Sci Sports 2020; 30:1008-1016. [PMID: 32153035 DOI: 10.1111/sms.13651] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2019] [Revised: 02/29/2020] [Accepted: 03/02/2020] [Indexed: 11/28/2022]
Abstract
OBJECTIVES To examine evidence of exercise-induced bronchoconstriction (EIB) defined as ≥10% reduction in forced expiratory volume in one second (FEV1 ) and exercise-induced arterial hypoxemia (EIAH) defined as ≥4% reduction in oxygen saturation (SpO2 ) from before to after participation in the Norseman Xtreme Triathlon. Secondarily, to assess whether changes in FEV1 and SpO2 are related to respiratory symptoms, training volume, and race time. METHODS In this quasi-experimental non-controlled study, we included 63 triathletes (50♂/13♀) aged 40.3 (±9.0) years (mean ± SD). Fifty-seven (46♂/11♀) measured lung function and 54 (44♂/10♀) measured SpO2 before the race, 8-10 minutes after the race (post-test 1) and the day after the race (post-test 2). Respiratory symptoms and training volume were recorded with modified AQUA questionnaire. ANOVA for repeated measures was used to detect differences in lung function and SpO2 . Statistical significance was accepted at 0.05 level. RESULTS Twenty-six participants (46%) presented with EIB at post-test 1 and 16 (28%) at post-test 2. Lung function variables were significantly reduced from baseline to post-test 1 and 2. Thirty-five participants (65%) showed evidence of mild to moderate EIAH. No significant correlations were observed except a weak correlation between maximal reduction in FEV1 and respiratory symptoms (r = 0.35, P = .016). CONCLUSION Our results demonstrated that 46% of the participants presented with EIB and 65% showed evidence of EIAH after the Norseman Xtreme Triathlon. Changes in FEV1 and SpO2 were not correlated to weekly training hours or race time. We observed a weak correlation between maximal reduction in FEV1 and respiratory symptoms.
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Affiliation(s)
- Trine Stensrud
- Department of Sports Medicine, Norwegian School of Sport Sciences, Oslo, Norway
| | - Øyvind Rossvoll
- Department of Sports Medicine, Norwegian School of Sport Sciences, Oslo, Norway
| | | | - Jørgen Melau
- Prehospital Division, Vestfold Hospital Trust, Tønsberg, Norway
| | - Camilla Illidi
- Department of Sports Medicine, Norwegian School of Sport Sciences, Oslo, Norway.,Centre of Health, Exercise and Performance, College of health & Life Sciences, Brunel University, London, UK
| | - Hege N Østgaard
- Department of Sports Medicine, Norwegian School of Sport Sciences, Oslo, Norway
| | - Jonny Hisdal
- Department of vascular surgery, Oslo University Hospital, Oslo, Norway.,Department of Clinical Medicine, University of Oslo, Oslo, Norway
| | - Julie Stang
- Department of Sports Medicine, Norwegian School of Sport Sciences, Oslo, Norway
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20
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Impact of a 10 km running trial on eryptosis, red blood cell rheology, and electrophysiology in endurance trained athletes: a pilot study. Eur J Appl Physiol 2019; 120:255-266. [PMID: 31776697 DOI: 10.1007/s00421-019-04271-x] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2019] [Accepted: 11/22/2019] [Indexed: 02/06/2023]
Abstract
PURPOSE Blood rheology is a key determinant of blood flow and tissue perfusion. There are still large discrepancies regarding the effects of an acute running exercise on blood rheological properties and red blood cell (RBC) physiology. We investigated the effect of a 10 km running trial on markers of blood rheology and RBC physiology in endurance trained athletes. METHODS Blood was sampled before and after the exercise to measure lactate and glucose, hematological and hemorheological parameters (blood viscosity, RBC deformability, and aggregation), eryptosis markers (phosphatidylserine and CD47 exposure, RBC reactive oxygen species), RBC-derived microparticles (RBC-MPs), and RBC electrophysiological activity. Weight was measured before and after exercise. Peripheral oxygen saturation and heart rate were monitored before and during the trial. RESULTS Blood lactate and glucose levels increased after exercise and subjects significantly lost weight. All athletes experienced a significant fall in oxygen saturation. Mean corpuscular volume (MCV) was increased from 95.1 ± 3.2 to 96.0 ± 3.3 and mean corpuscular hemoglobin concentration (MCHC) decreased after exercise suggesting a slight RBC rehydration. Exercise increased RBC deformability from 0.344 ± 0.04 to 0.378 ± 0.07, decreased RBC aggregates strength and blood viscosity, while hematocrit (Hct) remained unaffected. While RBC electrophysiological recording suggested a modulation in RBC calcium content and/or chloride conductance, eryptosis markers and RBC-MPs were not modified by the exercise. CONCLUSION A 10 km acute running exercise had no effect on RBC senescence and membrane blebbing. In contrast, this exercise increased RBC deformability, probably through rehydration process which resulted in a decrease in blood viscosity.
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Martin S, Hadmas R, Dobreanu D. Resting metabolic rate changes over 4 months of elite general roller ski training. Sci Sports 2019. [DOI: 10.1016/j.scispo.2019.04.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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22
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Cardinale DA, Larsen FJ, Lännerström J, Manselin T, Södergård O, Mijwel S, Lindholm P, Ekblom B, Boushel R. Influence of Hyperoxic-Supplemented High-Intensity Interval Training on Hemotological and Muscle Mitochondrial Adaptations in Trained Cyclists. Front Physiol 2019; 10:730. [PMID: 31258485 PMCID: PMC6587061 DOI: 10.3389/fphys.2019.00730] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2019] [Accepted: 05/27/2019] [Indexed: 11/13/2022] Open
Abstract
Background: Hyperoxia (HYPER) increases O2 carrying capacity resulting in a higher O2 delivery to the working muscles during exercise. Several lines of evidence indicate that lactate metabolism, power output, and endurance are improved by HYPER compared to normoxia (NORM). Since HYPER enables a higher exercise power output compared to NORM and considering the O2 delivery limitation at exercise intensities near to maximum, we hypothesized that hyperoxic-supplemented high-intensity interval training (HIIT) would upregulate muscle mitochondrial oxidative capacity and enhance endurance cycling performance compared to training in normoxia. Methods: 23 trained cyclists, age 35.3 ± 6.4 years, body mass 75.2 ± 9.6 kg, height 179.8 ± 7.9 m, and VO2max 4.5 ± 0.7 L min-1 performed 6 weeks polarized and periodized endurance training on a cycle ergometer consisting of supervised HIIT sessions 3 days/week and additional low-intensity training 2 days/week. Participants were randomly assigned to either HYPER (FIO2 0.30; n = 12) or NORM (FIO2 0.21; n = 11) breathing condition during HIIT. Mitochondrial respiration in permeabilized fibers and isolated mitochondria together with maximal and submaximal VO2, hematological parameters, and self-paced endurance cycling performance were tested pre- and posttraining intervention. Results: Hyperoxic training led to a small, non-significant change in performance compared to normoxic training (HYPER 6.0 ± 3.7%, NORM 2.4 ± 5.0%; p = 0.073, ES = 0.32). This small, beneficial effect on the self-paced endurance cycling performance was not explained by the change in VO2max (HYPER 1.1 ± 3.8%, NORM 0.0 ± 3.7%; p = 0.55, ES = 0.08), blood volume and hemoglobin mass, mitochondrial oxidative phosphorylation capacity (permeabilized fibers: HYPER 27.3 ± 46.0%, NORM 16.5 ± 49.1%; p = 0.37, ES = 3.24 and in isolated mitochondria: HYPER 26.1 ± 80.1%, NORM 15.9 ± 73.3%; p = 0.66, ES = 0.51), or markers of mitochondrial content which were similar between groups post intervention. Conclusions: This study showed that 6 weeks hyperoxic-supplemented HIIT led to marginal gain in cycle performance in already trained cyclists without change in VO2max, blood volume, hemoglobin mass, mitochondrial oxidative phosphorylation capacity, or exercise efficiency. The underlying mechanisms for the potentially meaningful performance effects of hyperoxia training remain unexplained and may raise ethical questions for elite sport.
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Affiliation(s)
- D A Cardinale
- Åstrand Laboratory, The Swedish School of Sport and Health Sciences, Stockholm, Sweden
| | - F J Larsen
- Åstrand Laboratory, The Swedish School of Sport and Health Sciences, Stockholm, Sweden
| | - J Lännerström
- Åstrand Laboratory, The Swedish School of Sport and Health Sciences, Stockholm, Sweden
| | - T Manselin
- Åstrand Laboratory, The Swedish School of Sport and Health Sciences, Stockholm, Sweden
| | - O Södergård
- Åstrand Laboratory, The Swedish School of Sport and Health Sciences, Stockholm, Sweden
| | - S Mijwel
- Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden
| | - P Lindholm
- Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden
| | - B Ekblom
- Åstrand Laboratory, The Swedish School of Sport and Health Sciences, Stockholm, Sweden
| | - R Boushel
- School of Kinesiology, Faculty of Education, University of British Columbia, Vancouver, BC, Canada
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23
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Dominelli PB, Sheel AW. Exercise-induced arterial hypoxemia; some answers, more questions. Appl Physiol Nutr Metab 2019; 44:571-579. [DOI: 10.1139/apnm-2018-0468] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Exercise-induced arterial hypoxemia (EIAH) is characterized by the decrease in arterial oxygen tension and oxyhemoglobin saturation during dynamic aerobic exercise. Since the time of the initial observations, our knowledge and understanding of EIAH has grown, but many unknowns remain. The purpose of this review is to provide an update on recent findings, highlight areas of disagreement, and identify where information is lacking. Specifically, this review will place emphasis on (i) the occurrence of EIAH during submaximal exercise, (ii) whether there are sex differences in the development and severity of EIAH, and (iii) unresolved questions and future directions.
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Affiliation(s)
- Paolo B. Dominelli
- Department of Anesthesiology, Mayo Clinic, 200 First Street SW, Rochester, MN 55905, USA
| | - A. William Sheel
- School of Kinesiology, The University of British Columbia, Vancouver, BC V6T 1Z4, Canada
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24
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Degens H, Stasiulis A, Skurvydas A, Statkeviciene B, Venckunas T. Physiological comparison between non-athletes, endurance, power and team athletes. Eur J Appl Physiol 2019; 119:1377-1386. [DOI: 10.1007/s00421-019-04128-3] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2018] [Accepted: 03/20/2019] [Indexed: 01/09/2023]
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Monitoring Exercise-Induced Muscle Fatigue and Adaptations: Making Sense of Popular or Emerging Indices and Biomarkers. Sports (Basel) 2018; 6:sports6040153. [PMID: 30486243 PMCID: PMC6315493 DOI: 10.3390/sports6040153] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2018] [Revised: 11/17/2018] [Accepted: 11/21/2018] [Indexed: 11/17/2022] Open
Abstract
Regular exercise with the appropriate intensity and duration may improve an athlete’s physical capacities by targeting different performance determinants across the endurance–strength spectrum aiming to delay fatigue. The mechanisms of muscle fatigue depend on exercise intensity and duration and may range from substrate depletion to acidosis and product inhibition of adenosinetriphosphatase (ATPase) and glycolysis. Fatigue mechanisms have been studied in isolated muscles; single muscle fibers (intact or skinned) or at the level of filamentous or isolated motor proteins; with each approach contributing to our understanding of the fatigue phenomenon. In vivo methods for monitoring fatigue include the assessment of various functional indices supported by the use of biochemical markers including blood lactate levels and more recently redox markers. Blood lactate measurements; as an accompaniment of functional assessment; are extensively used for estimating the contribution of the anaerobic metabolism to energy expenditure and to help interpret an athlete’s resistance to fatigue during high intensity exercise. Monitoring of redox indices is gaining popularity in the applied sports performance setting; as oxidative stress is not only a fatigue agent which may play a role in the pathophysiology of overtraining syndrome; but also constitutes an important signaling pathway for training adaptations; thus reflecting training status. Careful planning of sampling and interpretation of blood biomarkers should be applied; especially given that their levels can fluctuate according to an athlete’s lifestyle and training histories.
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Lopez-Pascual A, Arévalo J, Martínez JA, González-Muniesa P. Inverse Association Between Metabolic Syndrome and Altitude: A Cross-Sectional Study in an Adult Population of Ecuador. Front Endocrinol (Lausanne) 2018; 9:658. [PMID: 30483215 PMCID: PMC6240603 DOI: 10.3389/fendo.2018.00658] [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] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/22/2018] [Accepted: 10/19/2018] [Indexed: 12/23/2022] Open
Abstract
Background: Metabolic syndrome (MetS) is characterized by the clustering of hyperglycemia, hypertension, hypertriglyceridemia, low high-density lipoprotein cholesterol levels and central adiposity. Altitude has been proposed as a protective factor to prevent the development of MetS and its components. Aim: To determine whether living at geographical elevation is associated with MetS and its individual components after adjustment for potential confounders in an Ecuadoran population. Methods: The study included 260 Ecuadoran university graduates over 20 years of age, from the coastal or the Andean Altiplano region. The altitude of residence was imputed with the postal code of each participant residence according to the data of the Ecuadoran Geophysical Institute of the National Polytechnic School. MetS was defined according to the harmonizing definition. Logistic regression models were fitted to assess the relationship between altitude level and the prevalence of MetS and its individual components. To test the internal validity, re-sampling techniques were used (1,000 bootstrap samples). Results: Living at high altitude was associated with less hypercholesterolemia (OR = 0.24; p < 0.001), hyperglycemia (OR = 0.25; p < 0.05) and MetS (OR = 0.24; p < 0.05), after adjusting for potential confounders. At high altitude the bootstrapped logistic regression models showed lower prevalence of hypercholesterolemia (OR = 0.30; p < 0.05), hyperglycemia (OR = 0.22; p < 0.001) and MetS (OR = 0.28; p < 0.05). The MetS score (0-5 points) showed a reduction in the number of MetS components at high altitude compared to sea level (B = -0.34; p = 0.002). A statistically significant lower self-reported energy intake was found in high altitude compared to sea level after adjustment for potential confounders (p < 0.001). Conclusion: In the present study concerning a small Ecuadoran population composed of highly educated adults living at the coast and the Andean Altiplano, living at high altitude (2,758-2,787 m) was associated with a lower prevalence of MetS, hypercholesterolemia and hyperglycemia, compared to the participants at sea level (4-6 m). In addition, an inverse association between altitude and self-reported energy intake was found after adjusting for covariates, suggesting a physiological role of appetite at high altitude even in acclimated subjects.
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Affiliation(s)
- Amaya Lopez-Pascual
- Department of Nutrition, Food Science and Physiology, School of Pharmacy and Nutrition, University of Navarra, Pamplona, Spain
- Centre for Nutrition Research, School of Pharmacy and Nutrition, University of Navarra, Pamplona, Spain
| | - Jéssica Arévalo
- Department of Nutrition, Food Science and Physiology, School of Pharmacy and Nutrition, University of Navarra, Pamplona, Spain
| | - J. Alfredo Martínez
- Department of Nutrition, Food Science and Physiology, School of Pharmacy and Nutrition, University of Navarra, Pamplona, Spain
- Centre for Nutrition Research, School of Pharmacy and Nutrition, University of Navarra, Pamplona, Spain
- Nutrition Group, IdiSNA Navarra's Health Research Institute, Pamplona, Spain
- CIBERobn Physiopathology of Obesity and Nutrition, Centre of Biomedical Research Network, ISCIII, Madrid, Spain
- Madrid Institute of Advanced Studies (IMDEA Food), Food Institute, Madrid, Spain
| | - Pedro González-Muniesa
- Department of Nutrition, Food Science and Physiology, School of Pharmacy and Nutrition, University of Navarra, Pamplona, Spain
- Centre for Nutrition Research, School of Pharmacy and Nutrition, University of Navarra, Pamplona, Spain
- Nutrition Group, IdiSNA Navarra's Health Research Institute, Pamplona, Spain
- CIBERobn Physiopathology of Obesity and Nutrition, Centre of Biomedical Research Network, ISCIII, Madrid, Spain
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Gonzalez NC, Kuwahira I. Systemic Oxygen Transport with Rest, Exercise, and Hypoxia: A Comparison of Humans, Rats, and Mice. Compr Physiol 2018; 8:1537-1573. [PMID: 30215861 DOI: 10.1002/cphy.c170051] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
The objective of this article is to compare and contrast the known characteristics of the systemic O2 transport of humans, rats, and mice at rest and during exercise in normoxia and hypoxia. This analysis should help understand when rodent O2 transport findings can-and cannot-be applied to human responses to similar conditions. The O2 -transport system was analyzed as composed of four linked conductances: ventilation, alveolo-capillary diffusion, circulatory convection, and tissue capillary-cell diffusion. While the mechanisms of O2 transport are similar in the three species, the quantitative differences are naturally large. There are abundant data on total O2 consumption and on ventilatory and pulmonary diffusive conductances under resting conditions in the three species; however, there is much less available information on pulmonary gas exchange, circulatory O2 convection, and tissue O2 diffusion in mice. The scarcity of data largely derives from the difficulty of obtaining blood samples in these small animals and highlights the need for additional research in this area. In spite of the large quantitative differences in absolute and mass-specific O2 flux, available evidence indicates that resting alveolar and arterial and venous blood PO2 values under normoxia are similar in the three species. Additionally, at least in rats, alveolar and arterial blood PO2 under hypoxia and exercise remain closer to the resting values than those observed in humans. This is achieved by a greater ventilatory response, coupled with a closer value of arterial to alveolar PO2 , suggesting a greater efficacy of gas exchange in the rats. © 2018 American Physiological Society. Compr Physiol 8:1537-1573, 2018.
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Affiliation(s)
- Norberto C Gonzalez
- Department of Molecular and Integrative Physiology, University of Kansas Medical Center, Kansas City, Kansas, USA
| | - Ichiro Kuwahira
- Department of Pulmonary Medicine, Tokai University School of Medicine, Tokai University Tokyo Hospital, Tokyo, Japan
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28
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Brugniaux JV, Coombs GB, Barak OF, Dujic Z, Sekhon MS, Ainslie PN. Highs and lows of hyperoxia: physiological, performance, and clinical aspects. Am J Physiol Regul Integr Comp Physiol 2018; 315:R1-R27. [PMID: 29488785 DOI: 10.1152/ajpregu.00165.2017] [Citation(s) in RCA: 75] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Molecular oxygen (O2) is a vital element in human survival and plays a major role in a diverse range of biological and physiological processes. Although normobaric hyperoxia can increase arterial oxygen content ([Formula: see text]), it also causes vasoconstriction and hence reduces O2 delivery in various vascular beds, including the heart, skeletal muscle, and brain. Thus, a seemingly paradoxical situation exists in which the administration of oxygen may place tissues at increased risk of hypoxic stress. Nevertheless, with various degrees of effectiveness, and not without consequences, supplemental oxygen is used clinically in an attempt to correct tissue hypoxia (e.g., brain ischemia, traumatic brain injury, carbon monoxide poisoning, etc.) and chronic hypoxemia (e.g., severe COPD, etc.) and to help with wound healing, necrosis, or reperfusion injuries (e.g., compromised grafts). Hyperoxia has also been used liberally by athletes in a belief that it offers performance-enhancing benefits; such benefits also extend to hypoxemic patients both at rest and during rehabilitation. This review aims to provide a comprehensive overview of the effects of hyperoxia in humans from the "bench to bedside." The first section will focus on the basic physiological principles of partial pressure of arterial O2, [Formula: see text], and barometric pressure and how these changes lead to variation in regional O2 delivery. This review provides an overview of the evidence for and against the use of hyperoxia as an aid to enhance physical performance. The final section addresses pathophysiological concepts, clinical studies, and implications for therapy. The potential of O2 toxicity and future research directions are also considered.
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Affiliation(s)
| | - Geoff B Coombs
- Centre for Heart, Lung, and Vascular Health, University of British Columbia , Kelowna, British Columbia , Canada
| | - Otto F Barak
- Faculty of Medicine, University of Novi Sad, Novi Sad, Serbia.,Faculty of Sport and Physical Education, University of Novi Sad, Novi Sad, Serbia
| | - Zeljko Dujic
- Department of Integrative Physiology, School of Medicine, University of Split , Split , Croatia
| | - Mypinder S Sekhon
- Centre for Heart, Lung, and Vascular Health, University of British Columbia , Kelowna, British Columbia , Canada.,Division of Critical Care Medicine, Department of Medicine, Vancouver General Hospital, University of British Columbia , Vancouver, British Columbia , Canada
| | - Philip N Ainslie
- Centre for Heart, Lung, and Vascular Health, University of British Columbia , Kelowna, British Columbia , Canada
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29
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Kargl C, Arshad M, Salman F, Schurman RC, Del Corral P. 11β-hydroxysteroid dehydrogenase type-II activity is affected by grapefruit juice and intense muscular work. ARCHIVES OF ENDOCRINOLOGY AND METABOLISM 2017; 61:556-561. [PMID: 28977167 PMCID: PMC10522063 DOI: 10.1590/2359-3997000000296] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/17/2016] [Accepted: 06/12/2017] [Indexed: 11/21/2022]
Abstract
OBJECTIVE The enzymatic activity of 11β-hydroxysteroid dehydrogenase-2 (11β-HSD2) is key to protecting mineral corticoid receptors from cortisol and has been implicated in blood pressure regulation. Grapefruit juice (GFJ) and acidity are thought to inhibit this enzyme in vitro. This study examines the effect of GFJ and intense exercise on 11β-HSD2 enzyme activity in vivo. SUBJECTS AND METHODS Eighteen subjects ingested GFJ or apple juice (CON) on separate days prior to reporting to the laboratory in a randomized order. Saliva (Sal) samples were obtained at baseline, 15 and 45 minutes post-treadmill stress test; Sal cortisone (E) and cortisol (F) levels were determined, and the Sal cortisone:cortisol (E:F) ratio was used as an index of 11β-HSD2 enzyme activity at rest and after intense muscular work. RESULTS GFJ treatment decreased baseline 11β-HSD2 enzyme activity (44%) and Sal-E (28%) compared to CON (both, p < 0.05). Sal-E (r = 0.61, p < 0.05) and Sal-F (r = 0.66, p < 0.05) were correlated with diastolic blood pressure (DBP) in GFJ-treated individuals. Treadmill stress significantly increased Sal-E and Sal-F but did not alter 11β-HSD2 enzyme activity regardless of treatment. When treatments were examined separately, CON 11β-HSD2 enzyme activity decreased by 36% (p < 0.05) from baseline to 15 post-treadmill exercise. CONCLUSION Our findings suggest that GFJ and intense muscular work decrease 11β-HSD-2 activity independently, and no additive effect was noted. The association between DBP and the levels of Sal-F and Sal-E during the GFJ trial should be interpreted cautiously and warrants further investigation.
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Affiliation(s)
- Christopher Kargl
- Department of Biological SciencesBenedictine UniversityLisleILDepartment of Biological Sciences, Benedictine University, Lisle, IL
| | - Mohammad Arshad
- Department of Biological SciencesBenedictine UniversityLisleILDepartment of Biological Sciences, Benedictine University, Lisle, IL
| | - Fahad Salman
- Department of Biological SciencesBenedictine UniversityLisleILDepartment of Biological Sciences, Benedictine University, Lisle, IL
| | - Regina C. Schurman
- Department of Biological SciencesBenedictine UniversityLisleILDepartment of Biological Sciences, Benedictine University, Lisle, IL
| | - Pedro Del Corral
- Department of Biological SciencesBenedictine UniversityLisleILDepartment of Biological Sciences, Benedictine University, Lisle, IL
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30
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Moraga FA, Osorio J, Calderón-Jofré R, Pedreros A. Hemoconcentration During Maximum Exercise in Miners with Chronic Intermittent Exposure to Hypobaric Hypoxia (3800 m). High Alt Med Biol 2017; 19:15-20. [PMID: 29035586 DOI: 10.1089/ham.2017.0011] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Moraga, Fernando A., Jorge Osorio, Rodrigo Calderón-Jofré, and Andrés Pedreros. Hemoconcentration during maximum exercise in miners with chronic intermittent exposure to hypobaric hypoxia (3800 m). High Alt Med Biol. 19:15-20, 2018. OBJECTIVE To evaluate the effect of maximum exercise on hemoconcentration in miners with chronic intermittent hypobaric hypoxia (CIHH) at 3800 m. MATERIALS AND METHODS Sixteen miners with CIHH at high altitude (3800 m) were subjected to maximum exercise levels on a cycle ergometer, increasing exercise load by 50 W every 3 minutes at sea level and high altitude (3800 m). During exercise, arterial oxygen saturation and heart rate were measured. Blood samples were taken at each step to measure hemoglobin concentration and hematocrit. Arterial blood oxygen content was also calculated. RESULTS At sea level, a decrease in arterial oxygen saturation to 92.1% ± 2.5% was observed at 150 W and the hematocrit, hemoglobin concentration and oxygen content were not altered. At high altitude, arterial oxygen saturation decreased, reaching 88.2% ± 4.9% at 50 W and remained constant during the entire exercise protocol. Hemoglobin concentration and hematocrit increased reaching 16.4 ± 0.9 g/dL and 48.8% ± 1.6%, respectively, at 100 W and were maintained until recovery. Arterial oxygen content was constant during exercise and increased in the recovery period. CONCLUSION An increase in hemoglobin concentration during exercise compensates for the decline in arterial oxygen saturation, meanwhile arterial oxygen content remains constant.
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Affiliation(s)
- Fernando A Moraga
- 1 Laboratorio de Fisiología, Hipoxia y Función Vascular, Departamento de Ciencias Biomédicas, Facultad de Medicina, Universidad Católica del Norte , Coquimbo, Chile
| | - Jorge Osorio
- 2 Instituto de Estudios de la Salud , Universidad Arturo Prat, Iquique, Chile
| | - Rodrigo Calderón-Jofré
- 1 Laboratorio de Fisiología, Hipoxia y Función Vascular, Departamento de Ciencias Biomédicas, Facultad de Medicina, Universidad Católica del Norte , Coquimbo, Chile
| | - Andrés Pedreros
- 1 Laboratorio de Fisiología, Hipoxia y Función Vascular, Departamento de Ciencias Biomédicas, Facultad de Medicina, Universidad Católica del Norte , Coquimbo, Chile
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31
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Durmic T, Lazovic Popovic B, Zlatkovic Svenda M, Djelic M, Zugic V, Gavrilovic T, Mihailovic Z, Zdravkovic M, Leischik R. The training type influence on male elite athletes' ventilatory function. BMJ Open Sport Exerc Med 2017; 3:e000240. [PMID: 29021910 PMCID: PMC5633737 DOI: 10.1136/bmjsem-2017-000240] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/20/2017] [Indexed: 11/04/2022] Open
Abstract
Background/aim To assess and compare measured ventilatory volumes (forced expiratory volume in 1 s (FEV1), peak expirium flow (PEF) and maximal voluntary ventilation (MVV)), ventilatory function capacities (forced vital capacity (FVC) and vital capacity (VC)) and FEV1/VC ratio in a sample of power and endurance elite athletes and their age-matched and sex-matched sedentary control group. Methods A cross-sectional study was applied on male elite athletes (n=470) who were classified according to the type of the predominantly performed exercise in the following way: group 1: endurance group (EG=270), group 2: power athletes group (SG=200) and group 3: sedentary control group (CG=100). The lung VC, FVC, FEV1, FEV1/FVC ratio, PEF and MVV were measured in all of the observed subjects, who were also classified with regard to body mass index (BMI) and the percentage of the body fat (BF%). Results The CG had the highest BF% value, while the endurance group had the lowest BMI and BF% value, which is significantly different from the other two groups (p<0.05). The observed values of VC, FVC and FEV1 in the EG were significantly higher than those from the other two groups (p<0.05). There were no differences concerning the observed FEV1/FVC ratio. Conclusions A continued endurance physical activity leads to adaptive changes in spirometric parameters (VC, FVC and FEV1), highlighting the fact that there is a need for specific consideration of different respiratory ‘pattern’ development in different types of sport, which also has to be further evaluated.
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Affiliation(s)
- Tijana Durmic
- Institute of Forensic Medicine, School of Medicine, University of Belgrade, Belgrade, Serbia
| | - Biljana Lazovic Popovic
- University Clinical Center 'Zemun', Belgrade, Serbia.,School of Medicine, University of Belgrade, Belgrade, Serbia
| | - Mirjana Zlatkovic Svenda
- School of Medicine, University of Belgrade, Belgrade, Serbia.,Institute of Rheumatology, Belgrade, Serbia
| | - Marina Djelic
- Institute of Medical Physiology, School of Medicine, University of Belgrade, Belgrade, Serbia
| | - Vladimir Zugic
- School of Medicine, University of Belgrade, Belgrade, Serbia.,Clinic for Lung Diseases, Clinical Center of Serbia, Belgrade, Serbia
| | | | - Zoran Mihailovic
- Institute of Forensic Medicine, School of Medicine, University of Belgrade, Belgrade, Serbia
| | - Marija Zdravkovic
- School of Medicine, University of Belgrade, Belgrade, Serbia.,University Hospital Medical Center 'Bezanijska Kosa', Belgrade, Serbia
| | - Roman Leischik
- Department of Cardiology/Prevention and Sports Medicine, School of Medicine, University Witten/Herdecke, Hagen, Germany
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32
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Guimard A, Collomp K, Zorgati H, Brulaire S, Woorons X, Amiot V, Prieur F. Effect of swim intensity on responses to dynamic apnoea. J Sports Sci 2017; 36:1015-1021. [PMID: 28682161 DOI: 10.1080/02640414.2017.1349328] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
The aim of this study was to determine the influence of swim intensity on acute responses to dynamic apnoea. 9 swimmers performed one 50 m front crawl trial in four different conditions: at 400 m velocity (V400) with normal breathing (NB), at V400 in complete apnoea (Ap), at maximal velocity (Vmax) with NB and at Vmax in Ap. Peak heart rate (HRpeak), blood lactate concentration after exercise (Lacpost ex) and Borg rating of perceived exertion (RPE) were measured. Arterial oxygen saturation (SpO2) was monitored with a pulse oximeter at forehead level during and after exercise. In Ap, swimming at V400 induced a significantly lower HRpeak and Lacpost ex than swimming at Vmax whilst RPE and the kinetics of SpO2 were not different at V400 and at Vmax. The minimal value of SpO2 in Ap was reached 10 to 11 s after the end of V400 and Vmax (81.7 ± 10.1% and 84.4 ± 10.6%, respectively). Swimming a 50 m front crawl in Ap resulted in a large decrease in SpO2 which occurred only after the cessation of exercise. The higher duration of apnoea during submaximal exercise could explain why SpO2 and RPE reached the same values as for maximal exercise..
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Affiliation(s)
- A Guimard
- a CIAMS , Univ Paris-Sud, Université Paris Saclay , Orsay Cedex , France.,b CIAMS, Université d'Orléans , Orléans , France
| | - K Collomp
- a CIAMS , Univ Paris-Sud, Université Paris Saclay , Orsay Cedex , France.,b CIAMS, Université d'Orléans , Orléans , France .,c Département des Analyses , AFLD , Chatenay-Malabry , France
| | - H Zorgati
- d Laboratory of Physiology and Functional Explorations, Ibn Eljazzar Faculty of Medicine , University of Sousse , Sousse , Tunisia
| | - S Brulaire
- a CIAMS , Univ Paris-Sud, Université Paris Saclay , Orsay Cedex , France.,b CIAMS, Université d'Orléans , Orléans , France
| | - X Woorons
- e Unité de Recherche Pluridisciplinaire Sport Santé Société (URePSSS) -EA 7369 , Université de Lille , Lille , France
| | - V Amiot
- f Service de Médecine du Sport et d'Exploration Fonctionnelle Respiratoire , CHR Orléans La Source , Orléans Cedex 1 , France
| | - F Prieur
- a CIAMS , Univ Paris-Sud, Université Paris Saclay , Orsay Cedex , France.,b CIAMS, Université d'Orléans , Orléans , France
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Lopez-Pascual A, Bes-Rastrollo M, Sayón-Orea C, Perez-Cornago A, Díaz-Gutiérrez J, Pons JJ, Martínez-González MA, González-Muniesa P, Martínez JA. Living at a Geographically Higher Elevation Is Associated with Lower Risk of Metabolic Syndrome: Prospective Analysis of the SUN Cohort. Front Physiol 2017; 7:658. [PMID: 28101063 PMCID: PMC5209344 DOI: 10.3389/fphys.2016.00658] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2016] [Accepted: 12/14/2016] [Indexed: 11/13/2022] Open
Abstract
Living in a geographically higher altitude affects oxygen availability. The possible connection between environmental factors and the development of metabolic syndrome (MetS) feature is not fully understood, being the available epidemiological evidence still very limited. The aim of the present study was to evaluate the longitudinal association between altitude and incidence of MetS and each of its components in a prospective Spanish cohort, The Seguimiento Universidad de Navarra (SUN) project. Our study included 6860 highly educated subjects (university graduates) free from any MetS criteria at baseline. The altitude of residence was imputed with the postal code of each individual subject residence according to the data of the Spanish National Cartographic Institute and participants were categorized into tertiles. MetS was defined according to the harmonized definition. Cox proportional hazards models were used to assess the association between the altitude of residence and the risk of MetS during follow-up. After a median follow-up period of 10 years, 462 incident cases of MetS were identified. When adjusting for potential confounders, subjects in the highest category of altitude (>456 m) exhibited a significantly lower risk of developing MetS compared to those in the lowest tertile (<122 m) of altitude of residence [Model 2: Hazard ratio = 0.75 (95% Confidence interval: 0.58–0.97); p for trend = 0.029]. Living at geographically higher altitude was associated with a lower risk of developing MetS in the SUN project. Our findings suggest that geographical elevation may be an important factor linked to metabolic diseases.
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Affiliation(s)
- Amaya Lopez-Pascual
- Department of Nutrition, Food Science and Physiology, School of Pharmacy and Nutrition, University of NavarraPamplona, Spain; Centre for Nutrition Research, School of Pharmacy and Nutrition, University of NavarraPamplona, Spain
| | - Maira Bes-Rastrollo
- IDISNA Navarra's Health Research InstitutePamplona, Spain; CIBERobn Physiopathology of Obesity and Nutrition, Centre of Biomedical Research Network, ISCIIIMadrid, Spain; Department Preventive Medicine and Public Health, University of NavarraPamplona, Spain
| | - Carmen Sayón-Orea
- Department Preventive Medicine and Public Health, University of Navarra Pamplona, Spain
| | - Aurora Perez-Cornago
- Department Preventive Medicine and Public Health, University of NavarraPamplona, Spain; Cancer Epidemiology Unit, Nuffield Department of Population Health, University of OxfordOxford, UK
| | - Jesús Díaz-Gutiérrez
- Department Preventive Medicine and Public Health, University of Navarra Pamplona, Spain
| | - Juan J Pons
- IDISNA Navarra's Health Research InstitutePamplona, Spain; Department History, Art History, and Geography, University of NavarraPamplona, Spain
| | - Miguel A Martínez-González
- IDISNA Navarra's Health Research InstitutePamplona, Spain; CIBERobn Physiopathology of Obesity and Nutrition, Centre of Biomedical Research Network, ISCIIIMadrid, Spain; Department Preventive Medicine and Public Health, University of NavarraPamplona, Spain
| | - Pedro González-Muniesa
- Department of Nutrition, Food Science and Physiology, School of Pharmacy and Nutrition, University of NavarraPamplona, Spain; Centre for Nutrition Research, School of Pharmacy and Nutrition, University of NavarraPamplona, Spain; IDISNA Navarra's Health Research InstitutePamplona, Spain; CIBERobn Physiopathology of Obesity and Nutrition, Centre of Biomedical Research Network, ISCIIIMadrid, Spain
| | - J Alfredo Martínez
- Department of Nutrition, Food Science and Physiology, School of Pharmacy and Nutrition, University of NavarraPamplona, Spain; Centre for Nutrition Research, School of Pharmacy and Nutrition, University of NavarraPamplona, Spain; IDISNA Navarra's Health Research InstitutePamplona, Spain; CIBERobn Physiopathology of Obesity and Nutrition, Centre of Biomedical Research Network, ISCIIIMadrid, Spain
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34
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Díaz-Gutiérrez J, Martínez-González MÁ, Pons Izquierdo JJ, González-Muniesa P, Martínez JA, Bes-Rastrollo M. Living at Higher Altitude and Incidence of Overweight/Obesity: Prospective Analysis of the SUN Cohort. PLoS One 2016; 11:e0164483. [PMID: 27812092 PMCID: PMC5094724 DOI: 10.1371/journal.pone.0164483] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2016] [Accepted: 09/25/2016] [Indexed: 12/22/2022] Open
Abstract
BACKGROUND Residence at high altitude has been associated with lower obesity rates probably due to hypoxia conditions. However, there is no evidence of this association in a free-living population. OBJECTIVES We assessed the association between the altitude where each participant of a Spanish cohort (the SUN Project) was living and the incidence of overweight/obesity. METHODS The SUN Project is a dynamic, prospective, multipurpose cohort of Spanish university graduates with a retention rate of 89%. We included in the analysis 9 365 participants free of overweight/obesity at baseline. At the baseline questionnaire, participants reported their postal code and the time they had been living in their city/village. We imputed the altitude of each postal code according to the data of the Spanish National Cartographic Institute and categorized participants in tertiles. We used Cox regression models to adjust for potential confounding variables. RESULTS During a median follow-up of 10 years, we identified 2 156 incident cases of overweight/obesity. After adjusting for sex, age, time of residence at current city, baseline body mass index, physical activity, sedentarism and years of education (≤ 3 years, ≥ 4 years, Master/PhD), those participants in the third tertile (>456 m) exhibited a statistically significant 14% reduction in the risk of developing overweight/obesity in comparison to those in the first tertile (<124 m) (adjusted HR = 0.86; 95% CI: 0.77, 0.96). CONCLUSIONS Living in cities of higher altitude was inversely associated with the risk of developing overweight/obesity in a cohort of Spanish university graduates.
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Affiliation(s)
- Jesús Díaz-Gutiérrez
- University of Navarra, Department of Preventive Medicine and Public Health, School of Medicine, Pamplona, Spain
| | - Miguel Ángel Martínez-González
- University of Navarra, Department of Preventive Medicine and Public Health, School of Medicine, Pamplona, Spain
- IDISNA Navarra’s Health Research Institute, Pamplona, Spain
- CIBER Fisiopatología de la Obesidad y Nutrición (CIBERobn), Instituto de Salud Carlos III, Madrid, Spain
- Harvard TH Chan School of Public Health, Boston, United States of America
| | - Juan José Pons Izquierdo
- University of Navarra, Department of History, Art History, and Geography, School of Humanities and Social Sciences, Pamplona, Spain
| | - Pedro González-Muniesa
- IDISNA Navarra’s Health Research Institute, Pamplona, Spain
- CIBER Fisiopatología de la Obesidad y Nutrición (CIBERobn), Instituto de Salud Carlos III, Madrid, Spain
- University of Navarra, Department of Nutrition and Food Sciences and Physiology, School of Pharmacy, Pamplona, Spain
| | - J. Alfredo Martínez
- IDISNA Navarra’s Health Research Institute, Pamplona, Spain
- CIBER Fisiopatología de la Obesidad y Nutrición (CIBERobn), Instituto de Salud Carlos III, Madrid, Spain
- University of Navarra, Department of Nutrition and Food Sciences and Physiology, School of Pharmacy, Pamplona, Spain
| | - Maira Bes-Rastrollo
- University of Navarra, Department of Preventive Medicine and Public Health, School of Medicine, Pamplona, Spain
- IDISNA Navarra’s Health Research Institute, Pamplona, Spain
- CIBER Fisiopatología de la Obesidad y Nutrición (CIBERobn), Instituto de Salud Carlos III, Madrid, Spain
- * E-mail:
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Stavrou V, Toubekis AG, Karetsi E. Changes in Respiratory Parameters and Fin-Swimming Performance Following a 16-Week Training Period with Intermittent Breath Holding. J Hum Kinet 2015; 49:89-98. [PMID: 26839609 PMCID: PMC4723185 DOI: 10.1515/hukin-2015-0111] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/01/2015] [Indexed: 11/15/2022] Open
Abstract
The purpose of this study was to examine the effects of training with intermittent breath holding (IBH) on respiratory parameters, arterial oxygen saturation (SpO2) and performance. Twenty-eight fin-swimming athletes were randomly divided into two groups and followed the same training for 16 weeks. About 40% of the distance of each session was performed with self-selected breathing frequency (SBF group) or IBH (IBH group). Performance time of 50 and 400 m at maximum intensity was recorded and forced expired volume in 1 s (FEV1), forced vital capacity (FVC), peak expiratory flow (PEF) and SpO2 were measured before and after the 50 m test at baseline and post-training. Post-training, the respiratory parameters were increased in the IBH but remained unchanged in the SBF group (FEV1: 17 ±15% vs. -1 ±11%; FVC: 22 ±13% vs. 1 ±10%; PEF: 9 ±14% vs. -4 ±15%; p<0.05). Pre compared to post-training SpO2 was unchanged at baseline and decreased post-training following the 50 m test in both groups (p<0.05). The reduction was higher in the IBH compared to the SBF group (p<0.05). Performance in the 50 and 400 m tests improved in both groups, however, the improvement was greater in the IBH compared to the SBF group in both 50 and 400 m tests (p<0.05). The use of IBH is likely to enhance the load on the respiratory muscles, thus, contributing to improvement of the respiratory parameters. Decreased SpO2 after IBH is likely due to adaptation to hypoventilation. IBH favours performance improvement at 50 and 400 m fin-swimming.
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Affiliation(s)
- Vasileios Stavrou
- Department of Physical Education and Sport Science, University of Thessaly, Trikala, Greece; Medical School, Department of Cardio-Pulmonary Testing, Pulmonary Clinic, University of Thessaly, Larissa, Greece
| | - Argyris G Toubekis
- Faculty of Physical Education and Sport Science, Department of Aquatic Sports, University of Athens, Athens, Greece
| | - Eleni Karetsi
- Medical School, Department of Cardio-Pulmonary Testing, Pulmonary Clinic, University of Thessaly, Larissa, Greece
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Nybo L, Schmidt JF, Fritzdorf S, Nordsborg NB. Physiological characteristics of an aging Olympic athlete. Med Sci Sports Exerc 2015; 46:2132-8. [PMID: 24598701 DOI: 10.1249/mss.0000000000000331] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
PURPOSE To investigate the physiological basis of continued world-class performance of a world-class rower who won medals (three gold and two bronze) at five consecutive Olympic Games. METHODS From the age of 19 to 40 yr, maximal oxygen uptake (VO2 max), peak HR, blood lactate, and rowing ergometer performance were assessed annually. RESULTS During the first years of his elite career (from age 19 to 24), VO2 max increased from 5.5 to approximately 5.9 L · min(-1) (78 mL · min(-1) · kg(-1)) and his average power during 6-min maximal rowing increased from 420 to approximately 460 W. Although his HRmax declined by approximately 20 bpm during the 20-yr period, maximal aerobic power, evaluated both as VO2 max and 6-min test performance, was maintained until the age of 40. Furthermore, peak lactate levels remained unchanged and average power outputs during 10-s, 60-s, and 60-min ergometer tests were all maintained at approximately 800 W, approximately 700 W, and approximately 350 W, respectively, indicating that he was able to preserve both aerobic and anaerobic exercise performances. Echocardiographic analyses revealed a left ventricular mass of 198 g and left ventricular end-diastolic diameter of 5.8 cm. CONCLUSIONS This longitudinal case indicates that until the age of 40 yr, a steady increase in the oxygen pulse may have compensated for the significant decline in the maximal heart frequency. Furthermore, the maintenance of aerobic and anaerobic exercise capacities allowed this Olympic athlete to compete at the highest level for almost two decades.
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Affiliation(s)
- Lars Nybo
- 1Department of Nutrition, Exercise and Sports, University of Copenhagen, DENMARK; and 2Team Denmark, House of Sport, Brondby, DENMARK
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Jastrzębski Z, Żychowska M, Konieczna A, Ratkowski W, Radzimiński Ł. Changes in the acid-base balance and lactate concentration in the blood in amateur ultramarathon runners during a 100-km run. Biol Sport 2015; 32:261-5. [PMID: 26424931 PMCID: PMC4577565 DOI: 10.5604/20831862.1163372] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2014] [Revised: 04/13/2014] [Accepted: 02/02/2015] [Indexed: 12/11/2022] Open
Abstract
The aim of this study was to analyse the acid-base balance and partial pressure of blood gases of participants during a 100-km run. Fourteen experienced amateur ultramarathon runners (age: 43.36±11.83 years; height: 175.29±6.98 cm; weight: 72.12±7.36 kg) completed the 100-km run. Blood samples were taken before the run; after 25, 50, 75, and 100 km; and 12 and 24 hours after the run. There were significant differences (p<0.05) between the mean values registered for acid-alkaline balance, buffering alkalies, and current bicarbonate in each segment of the run, especially during the third, fourth, and fifth segments of the run (i.e., between 50 and 100 km), and there were only significant differences associated with buffering alkalies and current bicarbonate during the recovery. However, all the changes were within the physiological norm. A significant decrease in the compressibility of oxygen was observed after 100 km (from 92.80±15.67 to 88.36±13.71 mmHg) and continued during the recovery to 75.06±8.60 mmHg 12 h after the run. Also there was a decrease in saturation to a mean value of 93.78±3.10 at 12 h after the run. Generally the amateurs runners are able to adjust their running speed so as not to provoke a significant acid-base imbalance or lactate acid accumulation.
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Affiliation(s)
- Z Jastrzębski
- Gdansk University of Physical Education and Sport, Poland
| | - M Żychowska
- Gdansk University of Physical Education and Sport, Poland
| | - A Konieczna
- Gdansk University of Physical Education and Sport, Poland
| | - W Ratkowski
- Gdansk University of Physical Education and Sport, Poland
| | - Ł Radzimiński
- Gdansk University of Physical Education and Sport, Poland
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Kiyamu M, León-Velarde F, Rivera-Chira M, Elías G, Brutsaert TD. Developmental Effects Determine Submaximal Arterial Oxygen Saturation in Peruvian Quechua. High Alt Med Biol 2015; 16:138-46. [PMID: 25977978 DOI: 10.1089/ham.2014.1126] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Kiyamu, Melisa, Fabiola León-Velarde, María Rivera-Chira, Gianpietro Elías, and Tom D. Brutsaert. Developmental effects determine submaximal arterial oxygen saturation in Peruvian Quechua. High Alt Med Biol 16, 138-146, 2015.--Andean high altitude natives show higher arterial oxygen saturation (Sao(2)) during exercise in hypoxia, compared to acclimatized sojourners. In order to evaluate the effects of life-long exposure to high altitude on Sao(2), we studied two groups of well-matched, self-identified Peruvian Quechua natives who differed in their developmental exposure to hypoxia before and after a 2-month training period. Male and female volunteers (18-35 years) were recruited in Lima, Peru (150 m). The two groups were: a) Individuals who were born and raised at sea-level (BSL, n=34) and b) Individuals who were born and raised at high altitude (BHA, n=32), but who migrated to sea-level as adults (>16 years old). Exercise testing was conducted using a submaximal exercise protocol in normobaric hypoxia in Lima (BP=750 mmHg, Fio(2)=0.12), in order to measure Sao(2) (%), ventilation (VE L/min) and oxygen consumption (Vo(2), L/min). Repeated-measures ANOVA, controlling for VE/VO(2) (L/min) and sex during the submaximal protocol showed that BHA maintained higher Sao(2) (%) compared to BSL at all workloads before (p=0.005) and after training (p=0.017). As expected, both groups showed a decrease in Sao(2) (%) (p<0.001), as workload increased. Resting Sao(2) levels were not found to be different between groups. The results suggest that developmental exposure to altitude contributes to the maintenance of higher Sao(2) levels during submaximal exercise at hypoxia.
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Affiliation(s)
- Melisa Kiyamu
- 1 Departamento de Ciencias Biológicas y Fisiológicas, Universidad Peruana Cayetano Heredia , Urb. San Martín de Porres, Peru
| | - Fabiola León-Velarde
- 1 Departamento de Ciencias Biológicas y Fisiológicas, Universidad Peruana Cayetano Heredia , Urb. San Martín de Porres, Peru
| | - María Rivera-Chira
- 1 Departamento de Ciencias Biológicas y Fisiológicas, Universidad Peruana Cayetano Heredia , Urb. San Martín de Porres, Peru
| | - Gianpietro Elías
- 1 Departamento de Ciencias Biológicas y Fisiológicas, Universidad Peruana Cayetano Heredia , Urb. San Martín de Porres, Peru
| | - Tom D Brutsaert
- 2 Department of Exercise Science, Syracuse University , Syracuse, New York
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Kayser B. Pro: All dwellers at high altitude are persons of impaired physical and mental powers. High Alt Med Biol 2014; 14:205-7. [PMID: 24067175 DOI: 10.1089/ham.2013.1045] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Affiliation(s)
- Bengt Kayser
- Institute of Sports Sciences of the University of Lausanne , Lausanne, Switzerland
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Seixas DM, Seixas DMT, Pereira MC, Moreira MM, Paschoal IA. Oxygen desaturation in healthy subjects undergoing the incremental shuttle walk test. J Bras Pneumol 2014; 39:440-6. [PMID: 24068265 PMCID: PMC4075871 DOI: 10.1590/s1806-37132013000400007] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2013] [Accepted: 07/09/2013] [Indexed: 11/22/2022] Open
Abstract
OBJECTIVE To determine the probability of oxygen desaturation in healthy individuals undergoing the incremental shuttle walk test (ISWT). METHODS We enrolled 83 healthy subjects: 55 males (including 1 smoker) and 28 females. We determined pre-ISWT FEV1, FEV6, HR and SpO2, as well as post-ISWT HR and SpO2. RESULTS Mean values overall were as follows: age, 35.05 ± 12.53 years; body mass index, 24.30 ± 3.47 kg/m2; resting HR, 75.12 ± 12.48 bpm; resting SpO2, 97.96 ± 1.02%; FEV1, 3.75 ± 0.81 L; FEV6, 4.45 ± 0.87 L; FEV1/FEV6 ratio, 0.83 ± 0.08 (no restriction or obstruction); incremental shuttle walk distance, 958.30 ± 146.32 m; post-ISWT HR, 162.41 ± 18.24 bpm; and post-ISWT SpO2, 96.27 ± 2.21%. In 11 subjects, post-ISWT SpO2 was higher than was pre-ISWT SpO2. In 17 subjects, there was a 4% decrease in SpO2 after the ISWT. There were no statistically significant differences between the groups with and without post-ISWT oxygen desaturation in terms of age, gender, FEV1, FEV6, FEV1/FEV6, pre-ISWT SpO2, incremental shuttle walk distance, HR, or percentage of maximal HR. In the individuals with post-ISWT oxygen desaturation, the body mass index was higher (p = 0.01) and post-ISWT SpO2 was lower (p = 0.0001). CONCLUSIONS Healthy individuals can present oxygen desaturation after the ISWT. Using the ISWT to predict subtle respiratory abnormalities can be misleading. In healthy subjects, oxygen desaturation is common after the ISWT, as it is during any intense physical activity.
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Avaliação do comprometimento respiratório em pacientes com lúpus eritematoso sistêmico com o teste de caminhada de seis minutos. REVISTA BRASILEIRA DE REUMATOLOGIA 2014. [DOI: 10.1016/j.rbr.2014.02.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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Cairns SP. Holistic approaches to understanding mechanisms of fatigue in high-intensity sport. FATIGUE-BIOMEDICINE HEALTH AND BEHAVIOR 2013. [DOI: 10.1080/21641846.2013.765086] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Zhou J, Liu Y. Effects of genistein and estrogen on the genioglossus in rats exposed to chronic intermittent hypoxia may be HIF-1α dependent. Oral Dis 2013; 19:702-11. [DOI: 10.1111/odi.12060] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2012] [Revised: 11/16/2012] [Accepted: 12/09/2012] [Indexed: 01/06/2023]
Affiliation(s)
- J Zhou
- Department of Orthodontics; Stomatology School of Tongji University; Shanghai; China
| | - Y Liu
- Department of Orthodontics; Stomatology School of Tongji University; Shanghai; China
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Hanon C, Dorel S, Delfour-Peyrethon R, Leprêtre PM, Bishop DJ, Perrey S, Thomas C. Prevalence of cardio-respiratory factors in the occurrence of the decrease in oxygen uptake during supra-maximal, constant-power exercise. SPRINGERPLUS 2013; 2:651. [PMID: 25379364 PMCID: PMC4192145 DOI: 10.1186/2193-1801-2-651] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/10/2013] [Accepted: 11/18/2013] [Indexed: 12/05/2022]
Abstract
Purpose To investigate the physiological mechanisms that explain the end-exercise decrease in oxygen uptake during strenuous constant-power exercise, we recruited eleven trained, track cyclists. Methods On two separated days they performed 1) resting spirometric measures, followed by an incremental test on a cycle ergometer to determine the power output at and 2) an exhaustive isokinetic supramaximal cycling exercise (Tlimsupra) at 185 ± 24% of (i.e., 640.5 ± 50.8 W). During cycling exercise tests, , ventilation parameters, stroke volume (SV) and heart rate were continuously recorded. Furthermore, arterialised capillary blood samples were collected to measure blood pH, arterial oxygen saturation, lactate and bicarbonate concentration before and 5 min after Tlimsupra. Results A > 5% decrease in and/or SV was observed in 6 subjects, with 5 out of 6 subjects presenting both phenomena. The magnitude of the decrease was correlated with the magnitude of the SV decrease (R = 0.75, P < 0.01), the peak-exercise end-tidal O2 partial pressure (R = 0.80, P < 0.005) and the resting, forced expiratory volume in 1 s (R = 0.72, P < 0.05), but not with any blood variables. The significant post-Tlimsupra decrease in forced vital capacity and forced inspiratory volume corroborate with a possible respiratory muscle fatigue. Conclusion Based on these findings, we demonstrate that the occurrence of decrease in more than half of our subjects, during a strenuous constant-power exercise leading to a mild-acidosis (pH = 7.21 ± 0.04), results mainly from cardio-respiratory factors and not from blood metabolic responses.
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Affiliation(s)
- Christine Hanon
- French National Institute of Sports (INSEP), Research Department, Laboratory of Sport, Expertise and Performance, 11 Tremblay Avenue, 75012 Paris, France
| | - Sylvain Dorel
- French National Institute of Sports (INSEP), Research Department, Laboratory of Sport, Expertise and Performance, 11 Tremblay Avenue, 75012 Paris, France ; Laboratory "Motricité, Interactions, Performance" (EA 4334), University of Nantes, F-44000 Nantes, France
| | - Rémi Delfour-Peyrethon
- French National Institute of Sports (INSEP), Research Department, Laboratory of Sport, Expertise and Performance, 11 Tremblay Avenue, 75012 Paris, France ; Laboratory "Motricité, Interactions, Performance" (EA 4334), University of Nantes, F-44000 Nantes, France
| | | | - David J Bishop
- Institute of Sport, Exercise and Active Living (ISEAL), and the College of Sport and Exercise Science, Victoria University, Melbourne, Australia
| | - Stéphane Perrey
- Movement to Health (M2H), Montpellier-1 University, Euromov, Montpellier, France
| | - Claire Thomas
- French National Institute of Sports (INSEP), Research Department, Laboratory of Sport, Expertise and Performance, 11 Tremblay Avenue, 75012 Paris, France ; STAPS Department, University of Evry Val d'Essonne, François Mitterrand Boulevard, 91025 Evry, France
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Jacobs RA, Lundby C, Robach P, Gassmann M. Red blood cell volume and the capacity for exercise at moderate to high altitude. Sports Med 2012; 42:643-63. [PMID: 22741918 DOI: 10.1007/bf03262286] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Hypoxia-stimulated erythropoiesis, such as that observed when red blood cell volume (RCV) increases in response to high-altitude exposure, is well understood while the physiological importance is not. Maximal exercise tests are often performed in hypoxic conditions following some form of RCV manipulation in an attempt to elucidate oxygen transport limitations at moderate to high altitudes. Such attempts, however, have not made clear the extent to which RCV is of benefit to exercise at such elevations. Changes in RCV at sea level clearly have a direct influence on maximal exercise capacity. Nonetheless, at elevations above 3000 m, the evidence is not that clear. Certain studies demonstrate either a direct benefit or decrement to exercise capacity in response to an increase or decrease, respectively, in RCV whereas other studies report negligible effects of RCV manipulation on exercise capacity. Adding to the uncertainty regarding the importance of RCV at high altitude is the observation that Andean and Tibetan high-altitude natives exhibit similar exercise capacities at high altitude (3900 m) even though Andean natives often present with a higher percent haematocrit (Hct) when compared with both lowland natives and Tibetans. The current review summarizes past literature that has examined the effect of RCV changes on maximal exercise capacity at moderate to high altitudes, and discusses the explanation elucidating these seemingly paradoxical observations.
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Affiliation(s)
- Robert A Jacobs
- Institute of Veterinary Physiology, Vetsuisse Faculty, University of Zurich, Zurich, Switzerland
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Jacobs RA, Lundby C, Robach P, Gassmann M. Red Blood Cell Volume and the Capacity for Exercise at Moderate to High Altitude. Sports Med 2012. [DOI: 10.2165/11632440-000000000-00000] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
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Puthucheary Z, Skipworth JR, Rawal J, Loosemore M, Van Someren K, Montgomery HE. Genetic Influences in Sport and Physical Performance. Sports Med 2011; 41:845-59. [DOI: 10.2165/11593200-000000000-00000] [Citation(s) in RCA: 73] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
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The effect of exercise-induced hypoxemia on blood redox status in well-trained rowers. Eur J Appl Physiol 2011; 112:2073-83. [PMID: 21947454 DOI: 10.1007/s00421-011-2175-x] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2011] [Accepted: 09/08/2011] [Indexed: 01/24/2023]
Abstract
Exercise-induced arterial hypoxemia (EIAH), characterized by decline in arterial oxyhemoglobin saturation (SaO(2)), is a common phenomenon in endurance athletes. Acute intensive exercise is associated with the generation of reactive species that may result in redox status disturbances and oxidation of cell macromolecules. The purpose of the present study was to investigate whether EIAH augments oxidative stress as determined in blood plasma and erythrocytes in well-trained male rowers after a 2,000-m rowing ergometer race. Initially, athletes were assigned into either the normoxemic (n = 9, SaO(2) >92%, [Formula: see text]: 62.0 ± 1.9 ml kg(-1) min(-1)) or hypoxemic (n = 12, SaO(2) <92%, [Formula: see text]: 60.5 ± 2.2 ml kg(-1 )min(-1), mean ± SEM) group, following an incremental [Formula: see text] test on a wind resistance braked rowing ergometer. On a separate day the rowers performed a 2,000-m all-out effort on the same rowing ergometer. Following an overnight fast, blood samples were drawn from an antecubital vein before and immediately after the termination of the 2,000-m all-out effort and analyzed for selective oxidative stress markers. In both the normoxemic (SaO(2): 94.1 ± 0.9%) and hypoxemic (SaO(2): 88.6 ± 2.4%) rowers similar and significant exercise increase in serum thiobarbituric acid-reactive substances, protein carbonyls, catalase and total antioxidant capacity concentration were observed post-2,000 m all-out effort. Exercise significantly increased the oxidized glutathione concentration and decreased the ratio of reduced (GSH)-to-oxidized (GSSG) glutathione in the normoxemic group only, whereas the reduced form of glutathione remained unaffected in either groups. The increased oxidation of GSH to GSSG in erythrocytes of normoxemic individuals suggest that erythrocyte redox status may be affected by the oxygen saturation degree of hemoglobin. Our findings indicate that exercise-induced hypoxemia did not further affect the increased blood oxidative damage of lipids and proteins observed after a 2,000-m rowing ergometer race in highly-trained male rowers. The present data do not support any potential link between exercise-induced hypoxemia, oxidative stress increase and exercise performance.
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