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Titheradge P, Robergs R. Evaluating Airflow Sensor Methods: Precision in Indirect Calorimetry. Scand J Med Sci Sports 2024; 34:e14674. [PMID: 38895762 DOI: 10.1111/sms.14674] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2024] [Revised: 05/21/2024] [Accepted: 05/22/2024] [Indexed: 06/21/2024]
Abstract
This study assesses the impact of three volumetric gas flow measurement methods-turbine (fT); pneumotachograph (fP), and Venturi (fV)-on predictive accuracy and precision of expired gas analysis indirect calorimetry (EGAIC) across varying exercise intensities. Six males (Age: 38 ± 8 year; Height: 178.8 ± 4.2 cm;V ̇ O 2 peak $$ \dot{V}{\mathrm{O}}_2\mathrm{peak} $$ : 42 ± 2.8 mL O2 kg-1 min-1) and 14 females (Age = 44.6 ± 9.6 year; Height = 164.6 ± 6.9 cm;V ̇ O 2 peak $$ \dot{V}{\mathrm{O}}_2\mathrm{peak} $$ = 45 ± 8.6 mL O2 kg-1 min-1) were recruited. Participants completed physical exertion on a stationary cycle ergometer for simultaneous pulmonary minute ventilation (V ̇ $$ \dot{V} $$ ) measurements and EGAIC computations. Exercise protocols and subsequent conditions involved a 5-min cycling warm-up at 25 W min-1, incremental exercise to exhaustion (V ̇ O 2 $$ \dot{V}{\mathrm{O}}_2 $$ ramp test), then a steady-state exercise bout induced by a constant Watt load equivalent to 80% ventilatory threshold (80% VT). A linear mixed model revealed that exercise intensity significantly affectedV ̇ O 2 $$ \dot{V}{\mathrm{O}}_2 $$ measurements (p < 0.0001), whereas airflow sensor method (p = 0.97) and its interaction with exercise intensity (p = 0.91) did not. Group analysis of precision yielded aV ̇ O 2 $$ \dot{V}{\mathrm{O}}_2 $$ CV % = 21%; SEM = 5 mL O2 kg-1 min-1. Intra- and interindividual analysis of precision via Bland-Altman revealed a 95% confidence interval (CI) precision benchmark of 3-5 mL kg-1 min-1. Agreement among methods decreased at power outputs elicitingV ̇ $$ \dot{V} $$ up to 150 L min-1, indicating a decrease in precision and highlighting potential challenges in interpreting biological variability, training response heterogeneity, and test-retest comparisons. These findings suggest careful consideration of airflow sensor method variance across metabolic cart configurations.
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Affiliation(s)
- Praneel Titheradge
- School of Allied Health, Exercise & Sports Sciences, Charles Sturt University, Port Macquarie, New South Wales, Australia
| | - Robert Robergs
- School of Exercise & Nutrition Sciences, Faculty of Health, Queensland University of Technology, Brisbane, Queensland, Australia
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2
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Solleiro Pons M, Bernert L, Hume E, Hughes L, Williams ZJ, Burnley M, Ansdell P. No sex differences in oxygen uptake or extraction kinetics in the moderate or heavy exercise intensity domains. J Appl Physiol (1985) 2024; 136:472-481. [PMID: 38205552 PMCID: PMC11213575 DOI: 10.1152/japplphysiol.00429.2023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2023] [Revised: 01/02/2024] [Accepted: 01/04/2024] [Indexed: 01/12/2024] Open
Abstract
The integrative response to exercise differs between sexes, with oxidative energy contribution purported as a potential mechanism. The present study investigated whether this difference was evident in the kinetics of oxygen uptake (V̇o2) and extraction (HHb + Mb) during exercise. Sixteen adults (8 males, 8 females, age: 27 ± 5 yr) completed three experimental visits. Incremental exercise testing was performed to obtain lactate threshold and V̇o2peak. Subsequent visits involved three 6-min cycling bouts at 80% of lactate threshold and one 30-min bout at a work rate of 30% between the lactate threshold and power at V̇o2peak. Pulmonary gas exchange and near-infrared spectroscopy of the vastus lateralis were used to continuously sample V̇o2 and HHb + Mb, respectively. The phase II V̇o2 kinetics were quantified using monoexponential curves during moderate and heavy exercise. Slow component amplitudes were also quantified for the heavy-intensity domain. Relative V̇o2peak values were not different between sexes (P = 0.111). Males achieved ∼30% greater power outputs (P = 0.002). In the moderate- and heavy-intensity domains, the relative amplitude of the phase II transition was not different between sexes for V̇o2 (∼24 and ∼40% V̇o2peak, P ≥ 0.179) and HHb + Mb (∼20 and ∼32% ischemia, P ≥ 0.193). Similarly, there were no sex differences in the time constants for V̇o2 (∼28 s, P ≥ 0.385) or HHb + Mb (∼10 s, P ≥ 0.274). In the heavy-intensity domain, neither V̇o2 (P ≥ 0.686) or HHb + Mb (P ≥ 0.432) slow component amplitudes were different between sexes. The oxidative response to moderate- and heavy-intensity exercises did not differ between males and females, suggesting similar dynamic responses of oxidative metabolism during intensity-matched exercise.NEW & NOTEWORTHY This study demonstrated no sex differences in the oxidative response to moderate- and heavy-intensity cycling exercise. The change in oxygen uptake and deoxyhemoglobin were modeled with monoexponential curve fitting, which revealed no differences in the rate of oxidative energy provision between sexes. This provides insight into previously reported sex differences in the integrative response to exercise.
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Affiliation(s)
- Maria Solleiro Pons
- Department of Sport, Exercise and Rehabilitation, Faculty of Health and Life Sciences, Northumbria University, Newcastle upon Tyne, United Kingdom
| | - Lina Bernert
- Department of Sport, Exercise and Rehabilitation, Faculty of Health and Life Sciences, Northumbria University, Newcastle upon Tyne, United Kingdom
- Institute of Sport and Exercise Sciences, University of Münster, Münster, Germany
| | - Emily Hume
- Department of Sport, Exercise and Rehabilitation, Faculty of Health and Life Sciences, Northumbria University, Newcastle upon Tyne, United Kingdom
| | - Luke Hughes
- Department of Sport, Exercise and Rehabilitation, Faculty of Health and Life Sciences, Northumbria University, Newcastle upon Tyne, United Kingdom
| | - Zander J Williams
- Department of Respiratory Medicine, Royal Brompton Hospital, London, United Kingdom
| | - Mark Burnley
- School of Sport, Health and Exercise Sciences, Loughborough University, Loughborough, United Kingdom
| | - Paul Ansdell
- Department of Sport, Exercise and Rehabilitation, Faculty of Health and Life Sciences, Northumbria University, Newcastle upon Tyne, United Kingdom
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Dumbill R, Rabcuka J, Fallon J, Knight S, Hunter J, Voyce D, Barrett J, Ellen M, Weissenbacher A, Kurniawan T, Blonski S, Korczyk PM, Ploeg R, Coussios C, Friend P, Swietach P. Impaired O2 unloading from stored blood results in diffusion-limited O2 release at tissues: evidence from human kidneys. Blood 2024; 143:721-733. [PMID: 38048591 PMCID: PMC10900257 DOI: 10.1182/blood.2023022385] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2023] [Revised: 10/26/2023] [Accepted: 11/03/2023] [Indexed: 12/06/2023] Open
Abstract
ABSTRACT The volume of oxygen drawn from systemic capillaries down a partial pressure gradient is determined by the oxygen content of red blood cells (RBCs) and their oxygen-unloading kinetics, although the latter is assumed to be rapid and, therefore, not a meaningful factor. Under this paradigm, oxygen transfer to tissues is perfusion-limited. Consequently, clinical treatments to optimize oxygen delivery aim at improving blood flow and arterial oxygen content, rather than RBC oxygen handling. Although the oxygen-carrying capacity of blood is increased with transfusion, studies have shown that stored blood undergoes kinetic attrition of oxygen release, which may compromise overall oxygen delivery to tissues by causing transport to become diffusion-limited. We sought evidence for diffusion-limited oxygen release in viable human kidneys, normothermically perfused with stored blood. In a cohort of kidneys that went on to be transplanted, renal respiration correlated inversely with the time-constant of oxygen unloading from RBCs used for perfusion. Furthermore, the renal respiratory rate did not correlate with arterial O2 delivery unless this factored the rate of oxygen-release from RBCs, as expected from diffusion-limited transport. To test for a rescue effect, perfusion of kidneys deemed unsuitable for transplantation was alternated between stored and rejuvenated RBCs of the same donation. This experiment controlled oxygen-unloading, without intervening ischemia, holding all non-RBC parameters constant. Rejuvenated oxygen-unloading kinetics improved the kidney's oxygen diffusion capacity and increased cortical oxygen partial pressure by 60%. Thus, oxygen delivery to tissues can become diffusion-limited during perfusion with stored blood, which has implications in scenarios, such as ex vivo organ perfusion, major hemorrhage, and pediatric transfusion. This trial was registered at www.clinicaltrials.gov as #ISRCTN13292277.
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Affiliation(s)
- Richard Dumbill
- Nuffield Department of Surgery, University of Oxford, Oxford, United Kingdom
- Oxford Transplant Centre, Oxford University Hospitals NHS Foundation Trust, Oxford, United Kingdom
| | - Julija Rabcuka
- Department of Physiology, Anatomy & Genetics, University of Oxford, Oxford, United Kingdom
| | - John Fallon
- Nuffield Department of Surgery, University of Oxford, Oxford, United Kingdom
- Oxford Transplant Centre, Oxford University Hospitals NHS Foundation Trust, Oxford, United Kingdom
| | - Simon Knight
- Nuffield Department of Surgery, University of Oxford, Oxford, United Kingdom
- Oxford Transplant Centre, Oxford University Hospitals NHS Foundation Trust, Oxford, United Kingdom
| | - James Hunter
- Nuffield Department of Surgery, University of Oxford, Oxford, United Kingdom
- University Hospitals Coventry and Warwickshire NHS Trust, Coventry, United Kingdom
| | | | | | | | - Annemarie Weissenbacher
- Department of Visceral, Transplant and Thoracic Surgery, Center of Operative Medicine, Medical University of Innsbruck, Innsbruck, Austria
| | - Tetuko Kurniawan
- Institute of Fundamental Technological Research, Polish Academy of Sciences, Warsaw, Poland
- President University, Kota Jababeka, Bekasi, Indonesia
| | - Slawomir Blonski
- Institute of Fundamental Technological Research, Polish Academy of Sciences, Warsaw, Poland
| | - Piotr Michal Korczyk
- Institute of Fundamental Technological Research, Polish Academy of Sciences, Warsaw, Poland
| | - Rutger Ploeg
- Nuffield Department of Surgery, University of Oxford, Oxford, United Kingdom
- Oxford Transplant Centre, Oxford University Hospitals NHS Foundation Trust, Oxford, United Kingdom
| | - Constantin Coussios
- OrganOx Limited, Oxford, United Kingdom
- Institute of Biomedical Engineering, University of Oxford, Oxford, United Kingdom
| | - Peter Friend
- Nuffield Department of Surgery, University of Oxford, Oxford, United Kingdom
- Oxford Transplant Centre, Oxford University Hospitals NHS Foundation Trust, Oxford, United Kingdom
- OrganOx Limited, Oxford, United Kingdom
| | - Pawel Swietach
- Department of Physiology, Anatomy & Genetics, University of Oxford, Oxford, United Kingdom
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Mainzer G, Zucker-Toledano M, Hanna M, Bar-Yoseph R, Kodesh E. Significant exercise limitations after recovery from MIS-C related myocarditis. World J Pediatr 2023; 19:1149-1154. [PMID: 37127785 PMCID: PMC10150685 DOI: 10.1007/s12519-023-00722-w] [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] [Received: 07/22/2022] [Accepted: 03/30/2023] [Indexed: 05/03/2023]
Abstract
BACKGROUND Myocarditis is one of the presentations of multisystemic inflammatory syndrome in children (MIS-C) following coronavirus disease 2019 (COVID-19). Although the reported short-term prognosis is good, data regarding medium-term functional capacity and limitations are scarce. This study aimed to evaluate exercise capacity as well as possible cardiac and respiratory limitations in children recovered from MIS-C related myocarditis. METHODS Fourteen patients who recovered from MIS-C related myocarditis underwent spirometry and cardiopulmonary exercise testing (CPET), and their results were compared with an age-, sex-, weight- and activity level-matched healthy control group (n = 14). RESULTS All participants completed the CPET with peak oxygen uptake (peak [Formula: see text]), and the results were within the normal range (MIS-C 89.3% ± 8.9% and Control 87.9% ± 13.7% predicted [Formula: see text]). Five post-MIS-C patients (35%) had exercise-related cardio-respiratory abnormalities, including oxygen desaturation and oxygen-pulse flattening, compared to none in the control group. The MIS-C group also had lower peak exercise saturation (95.6 ± 3.5 vs. 97.6 ± 1.1) and lower breathing reserve (17.4% ± 7.5% vs. 27.4% ± 14.0% of MVV). CONCLUSIONS Patients who recovered from MIS-C related myocarditis may present exercise limitations. Functional assessment (e.g., CPET) should be included in routine examinations before allowing a return to physical activity in post-MIS-C myocarditis. Larger, longer term studies assessing functional capacity and focusing on physiological mechanisms are needed.
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Affiliation(s)
- Gur Mainzer
- Pediatric Heart Institute, Edmond and Lily Safra Children's Hospital, Sheba Medical Center, 52621, Tel Hashomer, Israel.
- Pediatric Cardiology Department, Hadassah Medical Center, Jerusalem, Israel.
- Pediatric Cardiology Unit, Padeh Medical Center, Poriya, Israel.
| | - Merav Zucker-Toledano
- Pediatric Cardiology Institute, Ruth Children's Hospital, Rambam Health Care Campus, Haifa, Israel
| | - Moneera Hanna
- Pediatric Pulmonary Institute, Ruth Children's Hospital, Rambam Health Care Campus, Haifa, Israel
| | - Ronen Bar-Yoseph
- Pediatric Pulmonary Institute, Ruth Children's Hospital, Rambam Health Care Campus, Haifa, Israel
- The Technion Faculty of Medicine, Haifa, Israel
| | - Einat Kodesh
- Pediatric Cardiology Unit, Padeh Medical Center, Poriya, Israel
- Department of Physical Therapy, Faculty of Social Welfare and Health Science, University of Haifa, Haifa, Israel
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Shiffman VJ, Rose P, Hughes B, Koehle MS, McKinney J, McKenzie DC, Leahy MG, Kipp S, Peters CM, Sheel AW. EXERCISE-INDUCED ARTERIAL HYPOXEMIA IN FEMALE MASTERS ATHTLETES. Respir Physiol Neurobiol 2023:104099. [PMID: 37385421 DOI: 10.1016/j.resp.2023.104099] [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: 03/09/2023] [Revised: 06/21/2023] [Accepted: 06/25/2023] [Indexed: 07/01/2023]
Abstract
The purpose of the study was to characterize exercise induced arterial hypoxemia (EIAH) in female masters athletes (FMA). We hypothesized that FMA would experience EIAH during treadmill running. Eight FMA (48-57 years) completed pulmonary function testing and an incremental exercise test until exhaustion (V̇O2max=45.7±6.5, range:35-54ml/kg/min). On a separate day, the participants were instrumented with a radial arterial catheter and an esophageal temperature probe. Participants performed three to four constant load exercise tests at 60-70, 75, 90, 95, and 100% of maximal oxygen uptake while sampling arterial blood and recording esophageal temperature. We found that FMA decrease their partial pressure of oxygen (86.0±7.6, range:73-108mmHg), arterial saturation (96.2±1.2, range:93-98%), and widen their alveolar to arterial oxygen difference (23.2±8.8, range:5-42mmHg) during all exercise intensities however, with variability in terms of severity and pattern. Our findings suggest that FMA experience EIAH however aerobic fitness appears unrelated to occurrence or severity (r=0.13, p=0.756).
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Affiliation(s)
- Viviana J Shiffman
- School of Kinesiology, The University of British Columbia, Vancouver, BC, Canada.
| | - Peter Rose
- Department of Anesthesia, Vancouver Coastal Health, Vancouver BC, Canada.
| | - Bevan Hughes
- Department of Anesthesia, Vancouver Coastal Health, Vancouver BC, Canada.
| | - Michael S Koehle
- School of Kinesiology, The University of British Columbia, Vancouver, BC, Canada; Division of Sport and Exercise Medicine, University of British Columbia, Vancouver, BC, Canada.
| | - James McKinney
- Division of Cardiology, University of British Columbia, Vancouver, BC, Canada.
| | - Donald C McKenzie
- School of Kinesiology, The University of British Columbia, Vancouver, BC, Canada; Division of Sport and Exercise Medicine, University of British Columbia, Vancouver, BC, Canada.
| | - Michael G Leahy
- School of Kinesiology, The University of British Columbia, Vancouver, BC, Canada.
| | - Shalaya Kipp
- School of Kinesiology, The University of British Columbia, Vancouver, BC, Canada.
| | - Carli M Peters
- School of Kinesiology, The University of British Columbia, Vancouver, BC, Canada.
| | - A William Sheel
- School of Kinesiology, The University of British Columbia, Vancouver, BC, Canada.
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6
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Lindner R, Raj IS, Yang AWH, Zaman S, Larsen B, Denham J. Moderate to Vigorous-intensity Continuous Training versus High-intensity Interval Training for improving VO2max in women: A systematic review and meta-analysis. Int J Sports Med 2023. [PMID: 37084758 DOI: 10.1055/a-2044-8952] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/23/2023]
Abstract
Traditional continuous training and high-intensity interval training (HIIT) can increase maximal oxygen uptake (V̇O2max). However, there is conflicting evidence regarding which form of training demonstrates the greatest improvements to V̇O2max, and data in women is sparse. We conducted a systematic review and meta-analyses to assess whether moderate to vigorous-intensity continuous training (MVICT) or HIIT was superior at improving V̇O2max in women. Randomised controlled and parallel studies examined the influence of MVICT and/or HIIT on V̇O2max in women. There was no statistical difference in V̇O2max improvements after training between women in the MVICT and HIIT cohorts (mean difference [MD]: -0.42, 95%CI: -1.43 to 0.60, p>0.05). Both MVICT and HIIT increased V̇O2max from baseline (MD: 3.20, 95% CI: 2.73 to 3.67 and MD: 3.16, 95% CI 2.09 to 4.24, respectively, p<0.001). Greater improvements in V̇O2max were observed in women who participated in more training sessions in both training formats. Long-HIIT was superior to short-HIIT protocols at increasing V̇O2max. Although MVICT and long-HIIT sessions elicited greater increases in V̇O2max in younger women compared to short-HIIT protocols, these differences were negligible in older women. Our findings suggest MVICT and HIIT are equally effective strategies for improving V̇O2max and indicate an effect of age on its response to training in women.
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Affiliation(s)
- Robert Lindner
- School of Health and Biomedical Sciences, RMIT University, Melbourne, Australia
| | - Isaac Selva Raj
- School of Health and Biomedical Sciences, RMIT University, Melbourne, Australia
- School of Medical and Health Sciences, Edith Cowan University, Joondalup, Australia
| | | | - Shadman Zaman
- School of Health and Biomedical Sciences, RMIT University, Melbourne, Australia
| | - Brianna Larsen
- School of Health and Medical Sciences, University of Southern Queensland, Toowoomba, Australia
- Institute for Resilient Regions Centre, Centre for Health Research, Toowoomba, Queensland, Australia
| | - Joshua Denham
- School of Health and Biomedical Sciences, RMIT University, Melbourne, Australia
- School of Health and Medical Sciences, University of Southern Queensland, Toowoomba, Australia
- Institute for Resilient Regions Centre, Centre for Health Research, Toowoomba, Queensland, Australia
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7
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THE RESPIRATORY PHYSIOLOGY OF EXERCISE: AGE AND SEX CONSIDERATIONS. CURRENT OPINION IN PHYSIOLOGY 2023. [DOI: 10.1016/j.cophys.2023.100652] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/06/2023]
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8
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Penichet-Tomas A, Jimenez-Olmedo JM, Pueo B, Olaya-Cuartero J. Physiological and Mechanical Responses to a Graded Exercise Test in Traditional Rowing. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2023; 20:3664. [PMID: 36834359 PMCID: PMC9964125 DOI: 10.3390/ijerph20043664] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/05/2023] [Revised: 02/14/2023] [Accepted: 02/16/2023] [Indexed: 06/18/2023]
Abstract
Maximum oxygen consumption and maximum power output are critical measures for training prescription in endurance sports such as rowing. The objective of this investigation was twofold: to compare the physiological and mechanical responses of female and male traditional rowers during a graded exercise test and to establish reference values in this specific rowing modality that have not yet been documented, unlike in Olympic rowing. Twenty-one highly trained/national level rowers participated in the study: 11 female (age: 30.1 ± 10.6 years, height: 167.3 ± 5.0 cm, body mass: 61.9 ± 4.9 kg) and 10 males (age: 33.5 ± 6.6 years, height: 180.8 ± 6.9 cm, body mass: 74.4 ± 6.9 kg). Significant differences (p < 0.05) were found in rowing performance between sexes, with a very large effect size (d = 7.2). The peak power output for the female rowers was 180.9 ± 11.4 W and 287.0 ± 17.7 W for the male rowers. The female rowers reached a VO2max of 51.2 ± 6.6 mL/kg/min at a mean of 174.5 ± 12.9 W, while the males' VO2max was 62.1 ± 4.7 mL/kg/min at a mean of 280.0 ± 20.5 W. These differences in VO2max and maximal aerobic capacity were significant (p < 0.05), with a large (d = 1.9) and very large (d = 6.2) effect size, respectively. A moderate association between VO2max, and rowing performance expressed in watts per kilogram of muscle mass was observed in the female rowers (r = 0.40, p = 0.228). For the male rowers, the correlation between VO2max and relative peak power output in watts per kilogram of body mass was strong (r = 0.68; p = 0.031). This study highlights the differences in the kinetics of ventilatory and mechanical parameters between female and male rowers and the importance of these differences for specific physical preparation in traditional rowing.
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Affiliation(s)
| | - Jose M. Jimenez-Olmedo
- Research Group in Health, Physical Activity, and Sports Technology (Health-Tech), Faculty of Education, University of Alicante, 03690 San Vicente del Raspeig, Spain
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Ferretti G, Fagoni N, Taboni A, Vinetti G, di Prampero PE. 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] [MESH Headings] [Grants] [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 ([Formula: see text]) 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 [Formula: see text] 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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Affiliation(s)
- Guido Ferretti
- Dipartimento di Medicina Molecolare e Traslazionale, Università di Brescia, Brescia, Italy.
- Département d'Anesthésiologie, Pharmacologie et Soins Intensifs, Université de Genève, Genève, Switzerland.
| | - Nazzareno Fagoni
- Dipartimento di Medicina Molecolare e Traslazionale, Università di Brescia, Brescia, Italy
| | - Anna Taboni
- Département d'Anesthésiologie, Pharmacologie et Soins Intensifs, Université de Genève, Genève, Switzerland
| | - Giovanni Vinetti
- Dipartimento di Medicina Molecolare e Traslazionale, Università di Brescia, Brescia, Italy
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Dominelli PB, Molgat-Seon Y. Sex, gender and the pulmonary physiology of exercise. Eur Respir Rev 2022; 31:31/163/210074. [PMID: 35022254 PMCID: PMC9488949 DOI: 10.1183/16000617.0074-2021] [Citation(s) in RCA: 21] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2021] [Accepted: 07/09/2021] [Indexed: 01/11/2023] Open
Abstract
In this review, we detail how the pulmonary system's response to exercise is impacted by both sex and gender in healthy humans across the lifespan. First, the rationale for why sex and gender differences should be considered is explored, and then anatomical differences are highlighted, namely that females typically have smaller lungs and airways than males. Thereafter, we describe how these anatomical differences can impact functional aspects such as respiratory muscle energetics and activation, mechanical ventilatory constraints, diaphragm fatigue, and pulmonary gas exchange in healthy adults and children. Finally, we detail how gender can impact the pulmonary response to exercise. Biological sex can influence the pulmonary response to exercise in healthy individuals across the lifespanhttps://bit.ly/3ejMDrv
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Affiliation(s)
| | - Yannick Molgat-Seon
- Dept of Kinesiology and Applied Health, University of Winnipeg, Winnipeg, MB, Canada.,Centre for Heart and Lung Innovation, Providence Health Care Research Institute, St Paul's Hospital, Vancouver, BC, Canada
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11
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Commentaries on Viewpoint: Consider iron status when making sex comparisons in human physiology. J Appl Physiol (1985) 2022; 132:703-709. [PMID: 35274549 DOI: 10.1152/japplphysiol.00016.2022] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
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12
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Hallam LC, Amorim FT. Expanding the Gap: An Updated Look Into Sex Differences in Running Performance. Front Physiol 2022; 12:804149. [PMID: 35058806 PMCID: PMC8764368 DOI: 10.3389/fphys.2021.804149] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2021] [Accepted: 11/29/2021] [Indexed: 12/31/2022] Open
Abstract
Males consistently outperform females in athletic endeavors, including running events of standard Olympic distances (100 m to Marathon). The magnitude of this percentage sex difference, i.e., the sex gap, has evolved over time. Two clear trends in sex gap evolution are evident; a narrowing of the gap during the 20th century, followed by a period of stability thereafter. However, an updated perspective on the average sex gap from top 20 athlete performances over the past two decades reveals nuanced trends over time, indicating the sex gap is not fixed. Additionally, the sex gap varies with performance level; the difference in absolute running performance between males and females is lowest for world record/world lead performances and increases in lower-ranked elite athletes. This observation of an increased sex gap with world rank is evident in events 400 m and longer and indicates a lower depth in female competitive standards. Explanations for the sex difference in absolute performance and competition depth include physical (physiological, anatomical, neuromuscular, biomechanical), sociocultural, psychological, and sport-specific factors. It is apparent that females are the disadvantaged sex in sport; therefore, measures should be taken to reduce this discrepancy and enable both sexes to reach their biological performance potential. There is scope to narrow the sex performance gap by addressing inequalities between the sexes in opportunities, provisions, incentives, attitudes/perceptions, research, and media representation.
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Affiliation(s)
- Lydia C Hallam
- Exercise Physiology Laboratory, Department of Health, Exercise, and Sport Science, University of New Mexico, Albuquerque, NM, United States
| | - Fabiano T Amorim
- Exercise Physiology Laboratory, Department of Health, Exercise, and Sport Science, University of New Mexico, Albuquerque, NM, United States
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13
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Zhao J, Ding Y, Kline GP, Zhou Z, Mallet RT, Shi X. Hypoxic breathing produces more intense hypoxemia in elderly women than in elderly men. Front Physiol 2022; 13:989635. [PMID: 36388125 PMCID: PMC9644051 DOI: 10.3389/fphys.2022.989635] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2022] [Accepted: 10/12/2022] [Indexed: 12/03/2022] Open
Abstract
Background: Brief hypoxic exposures are increasingly applied as interventions for aging-related conditions. To optimize the therapeutic impact of hypoxia, knowledge of the sex-related differences in physiological responses to hypoxia is essential. This study compared hypoxia-induced hypoxemic responses in elderly men and women. Methods: Seven elderly men (70.3 ± 6.0 years old) and nine women (69.4 ± 5.5 years old) breathed 10% O2 for 5 min while arterial (SaO2; transcutaneous photoplethysmography) and cerebral tissue O2 saturation (ScO2; near-infrared spectroscopy), ventilatory frequency, tidal volume, minute-ventilation, and partial pressures of end-tidal O2 (PETO2) and CO2 (mass spectrometry) were continuously monitored. Cerebral tissue oxygen extraction fraction (OEF) equaled (SaO2-ScO2)/SaO2. Results: During 5 min hypoxia SaO2 fell from 97.0 ± 0.8% to 80.6 ± 4.6% in the men and from 96.3 ± 1.4% to 72.6 ± 4.0% in the women. The slope ΔSaO2/min was steeper in the women than the men (-4.71 ± 0.96 vs. -3.24 ± 0.76%/min; p = 0.005). Although SaO2 fell twice as sharply per unit decrease in PETO2 in the women than the men (-1.13 ± 0.11 vs. -0.54 ± 0.06%/mmHg; p = 0.003), minute-ventilation per unit hypoxemia increased less appreciably in the women (-0.092 ± 0.014 vs. -0.160 ± 0.021 L/min/%; p = 0.023). OEF fell with hypoxia duration in the women, but remained stable in the men. Conclusion: During 5 min hypoxic breathing, elderly women experience more intense hypoxemia and reduced chemoreflex sensitivity vs. their male counterparts, which may lower OEF stability in women despite augmented O2 dissociation from hemoglobin during hypoxia. These sex-related differences merit attention when implementing brief hypoxic exposures for therapeutic purposes.
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Affiliation(s)
- Jinfeng Zhao
- Departments of Pharmacology and Neuroscience, School of Biomedical Sciences, University of North Texas Health Science Center, Fort Worth, TX, United States.,School of Physical Education, Shanxi University, Taiyuan, China
| | - Yanfeng Ding
- Internal Medicine, University of North Texas Health Science Center, Fort Worth, TX, United States
| | - Geoffrey P Kline
- Internal Medicine, University of North Texas Health Science Center, Fort Worth, TX, United States
| | - Zhengyang Zhou
- Biostatistics and Epidemiology, School of Public Health, University of North Texas Health Science Center, Fort Worth, TX, United States
| | - Robert T Mallet
- Physiology and Anatomy, School of Biomedical Sciences, University of North Texas Health Science Center, Fort Worth, TX, United States
| | - Xiangrong Shi
- Departments of Pharmacology and Neuroscience, School of Biomedical Sciences, University of North Texas Health Science Center, Fort Worth, TX, United States
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14
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Ade CJ, Turpin VRG, Parr SK, Hammond ST, White Z, Weber RE, Schulze KM, Colburn TD, Poole DC. Does wearing a facemask decrease arterial blood oxygenation and impair exercise tolerance? Respir Physiol Neurobiol 2021; 294:103765. [PMID: 34352384 PMCID: PMC9715989 DOI: 10.1016/j.resp.2021.103765] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2021] [Revised: 07/12/2021] [Accepted: 07/25/2021] [Indexed: 12/14/2022]
Abstract
INTRODUCTION Concerns have been raised that COVID-19 face coverings compromise lung function and pulmonary gas exchange to the extent that they produce arterial hypoxemia and hypercapnia during high intensity exercise resulting in exercise intolerance in recreational exercisers. This study therefore aimed to investigate the effects of a surgical, flannel or vertical-fold N95 masks on cardiorespiratory responses to incremental exercise. METHODS This investigation studied 11 adult males and females at rest and while performing progressive cycle exercise to exhaustion. We tested the hypotheses that wearing a surgical (S), flannel (F) or horizontal-fold N95 mask compared to no mask (control) would not promote arterial deoxygenation or exercise intolerance nor alter primary cardiovascular variables during submaximal or maximal exercise. RESULTS Despite the masks significantly increasing end-expired peri-oral %CO2 and reducing %O2, each ∼0.8-2% during exercise (P < 0.05), our results supported the hypotheses. Specifically, none of these masks reduced sub-maximal or maximal exercise arterial O2 saturation (P = 0.744), but ratings of dyspnea were significantly increased (P = 0.007). Moreover, maximal exercise capacity was not compromised nor were there any significant alterations of primary cardiovascular responses (mean arterial pressure, stroke volume, cardiac output) found during sub-maximal exercise. CONCLUSION Whereas these results are for young healthy recreational male and female exercisers and cannot be applied directly to elite athletes, older or patient populations, they do support that arterial hypoxemia and exercise intolerance are not the obligatory consequences of COVID-19-indicated mask-wearing at least for cycling exercise.
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Affiliation(s)
- Carl J Ade
- Departments of Kinesiology, Kansas State University, Manhattan, KS, 66506, USA.
| | | | - Shannon K Parr
- Departments of Kinesiology, Kansas State University, Manhattan, KS, 66506, USA
| | - Stephen T Hammond
- Departments of Kinesiology, Kansas State University, Manhattan, KS, 66506, USA
| | - Zachary White
- Departments of Kinesiology, Kansas State University, Manhattan, KS, 66506, USA
| | - Ramona E Weber
- Departments of Kinesiology, Kansas State University, Manhattan, KS, 66506, USA; Anatomy and Physiology, Kansas State University, Manhattan, KS, 66506, USA
| | - Kiana M Schulze
- Departments of Kinesiology, Kansas State University, Manhattan, KS, 66506, USA; Anatomy and Physiology, Kansas State University, Manhattan, KS, 66506, USA
| | - Trenton D Colburn
- Departments of Kinesiology, Kansas State University, Manhattan, KS, 66506, USA; Anatomy and Physiology, Kansas State University, Manhattan, KS, 66506, USA
| | - David C Poole
- Departments of Kinesiology, Kansas State University, Manhattan, KS, 66506, USA; Anatomy and Physiology, Kansas State University, Manhattan, KS, 66506, USA
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15
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Martín-Escudero P, Cabanas AM, Fuentes-Ferrer M, Galindo-Canales M. Oxygen Saturation Behavior by Pulse Oximetry in Female Athletes: Breaking Myths. BIOSENSORS-BASEL 2021; 11:bios11100391. [PMID: 34677347 PMCID: PMC8534025 DOI: 10.3390/bios11100391] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/09/2021] [Revised: 09/30/2021] [Accepted: 10/05/2021] [Indexed: 12/18/2022]
Abstract
The myths surrounding women’s participation in sport have been reflected in respiratory physiology. This study aims to demonstrate that continuous monitoring of blood oxygen saturation during a maximal exercise test in female athletes is highly correlated with the determination of the second ventilatory threshold (VT2) or anaerobic threshold (AnT). The measurements were performed using a pulse oximeter during a maximum effort test on a treadmill on a population of 27 healthy female athletes. A common behavior of the oxygen saturation evolution during the incremental exercise test characterized by a decrease in saturation before the aerobic threshold (AeT) followed by a second significant drop was observed. Decreases in peripheral oxygen saturation during physical exertion have been related to the athlete’s physical fitness condition. However, this drop should not be a limiting factor in women’s physical performance. We found statistically significant correlations between the maximum oxygen uptake and the appearance of the ventilatory thresholds (VT1 and VT2), the desaturation time, the total test time, and between the desaturation time and the VT2. We observed a relationship between the desaturation time and the VT2 appearance. Indeed, a linear regression model between the desaturation time and the VT2 appearance can predict 80% of the values in our sample. Besides, we suggest that pulse oximetry is a simple, fairly accurate, and non-invasive technique for studying the physical condition of athletes who perform physical exertion.
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Affiliation(s)
- Pilar Martín-Escudero
- Professional Medical School of Physical Education and Sport, Faculty of Medicine, Universidad Complutense de Madrid, 28040 Madrid, Spain; (P.M.-E.); (M.G.-C.)
| | - Ana María Cabanas
- Departamento de Física, Universidad de Tarapacá, Arica 1010064, Chile
- Correspondence:
| | - Manuel Fuentes-Ferrer
- Unit of Clinical Management (UGC), Department of Preventive Medicine, Hospital Clínico San Carlos, 28040 Madrid, Spain;
| | - Mercedes Galindo-Canales
- Professional Medical School of Physical Education and Sport, Faculty of Medicine, Universidad Complutense de Madrid, 28040 Madrid, Spain; (P.M.-E.); (M.G.-C.)
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16
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Evaluation of sex-based differences in airway size and the physiological implications. Eur J Appl Physiol 2021; 121:2957-2966. [PMID: 34331574 DOI: 10.1007/s00421-021-04778-2] [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: 02/18/2021] [Accepted: 07/26/2021] [Indexed: 10/20/2022]
Abstract
Recent evidence suggests healthy females have significantly smaller central conducting airways than males when matched for either height or lung volume during analysis. This anatomical sex-based difference could impact the integrative response to exercise. Our review critically evaluates the literature on direct and indirect techniques to measure central conducting airway size and their limitations. We present multiple sources highlighting the difference between male and female central conducting airway size in both pediatric and adult populations. Following the discussion of measurement techniques and results, we discuss the functional implications of these differences in central conducting airway size, including work of breathing, oxygen cost of breathing, and how these impacts will continue into elderly populations. We then discuss a range of topics for the future direction of airway differences and the benefits they could provide to both healthy and diseased populations. Specially, these sex-differences in central conducting airway size could result in different aerosol deposition or how lung disease manifests. Finally, we detail emerging techniques that uniquely allow for high-resolution imaging to be paired with detailed physiological measures.
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17
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Lima-Silva AE, Cristina-Souza G, Silva-Cavalcante MD, Bertuzzi R, Bishop DJ. Caffeine during High-Intensity Whole-Body Exercise: An Integrative Approach beyond the Central Nervous System. Nutrients 2021; 13:2503. [PMID: 34444663 PMCID: PMC8400708 DOI: 10.3390/nu13082503] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2021] [Revised: 07/15/2021] [Accepted: 07/19/2021] [Indexed: 11/16/2022] Open
Abstract
Caffeine is one of the most consumed ergogenic aids around the world. Many studies support the ergogenic effect of caffeine over a large spectrum of exercise types. While the stimulatory effect of caffeine on the central nervous system is the well-accepted mechanism explaining improvements in exercise performance during high-intensity whole-body exercise, in which other physiological systems such as pulmonary, cardiovascular, and muscular systems are maximally activated, a direct effect of caffeine on such systems cannot be ignored. A better understanding of the effects of caffeine on multiple physiological systems during high-intensity whole-body exercise might help to expand its use in different sporting contexts (e.g., competitions in different environments, such as altitude) or even assist the treatment of some diseases (e.g., chronic obstructive pulmonary disease). In the present narrative review, we explore the potential effects of caffeine on the pulmonary, cardiovascular, and muscular systems, and describe how such alterations may interact and thus contribute to the ergogenic effects of caffeine during high-intensity whole-body exercise. This integrative approach provides insights regarding how caffeine influences endurance performance and may drive further studies exploring its mechanisms of action in a broader perspective.
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Affiliation(s)
- Adriano E. Lima-Silva
- Human Performance Research Group, Federal University of Technology Parana (UTFPR), Curitiba 81310900, PR, Brazil; (A.E.L.-S.); (G.C.-S.)
| | - Gislaine Cristina-Souza
- Human Performance Research Group, Federal University of Technology Parana (UTFPR), Curitiba 81310900, PR, Brazil; (A.E.L.-S.); (G.C.-S.)
- Nutrition and Exercise Research Group, State University of Minas Gerais (UEMG), Passos 37902092, MG, Brazil
| | - Marcos D. Silva-Cavalcante
- Postgraduate Program in Nutrition (PPGNUT), Faculty of Nutrition (FANUT), Federal University of Alagoas (UFAL), Maceio 57072900, AL, Brazil;
| | - Romulo Bertuzzi
- Endurance Sports Research Group (GEDAE-USP), University of São Paulo, Sao Paulo 05508030, SP, Brazil;
| | - David J. Bishop
- Institute for Health and Sport (IHES), Victoria University, Melbourne, VIC 8001, Australia
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18
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Collins SÉ, Phillips DB, Brotto AR, Rampuri ZH, Stickland MK. Ventilatory efficiency in athletes, asthma and obesity. Eur Respir Rev 2021; 30:30/161/200206. [PMID: 34289980 DOI: 10.1183/16000617.0206-2020] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2020] [Accepted: 09/16/2020] [Indexed: 11/05/2022] Open
Abstract
During submaximal exercise, minute ventilation (V' E) increases in proportion to metabolic rate (i.e. carbon dioxide production (V' CO2 )) to maintain arterial blood gas homeostasis. The ratio V' E/V' CO2 , commonly termed ventilatory efficiency, is a useful tool to evaluate exercise responses in healthy individuals and patients with chronic disease. Emerging research has shown abnormal ventilatory responses to exercise (either elevated or blunted V' E/V' CO2 ) in some chronic respiratory and cardiovascular conditions. This review will briefly provide an overview of the physiology of ventilatory efficiency, before describing the ventilatory responses to exercise in healthy trained endurance athletes, patients with asthma, and patients with obesity. During submaximal exercise, the V' E/V' CO2 response is generally normal in endurance-trained individuals, patients with asthma and patients with obesity. However, in endurance-trained individuals, asthmatics who demonstrate exercise induced-bronchoconstriction, and morbidly obese individuals, the V' E/V' CO2 can be blunted at maximal exercise, likely because of mechanical ventilatory constraint.
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Affiliation(s)
- Sophie É Collins
- Division of Pulmonary Medicine, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, Canada.,Faculty of Rehabilitation Medicine, University of Alberta, Edmonton, Canada
| | - Devin B Phillips
- Respiratory Investigation Unit, Department of Medicine, Queen's University, Kingston, Canada
| | - Andrew R Brotto
- Division of Pulmonary Medicine, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, Canada
| | - Zahrah H Rampuri
- Division of Pulmonary Medicine, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, Canada.,Faculty of Rehabilitation Medicine, University of Alberta, Edmonton, Canada
| | - Michael K Stickland
- Division of Pulmonary Medicine, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, Canada.,G.F. MacDonald Centre for Lung Health, Covenant Health, Edmonton, Canada
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19
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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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20
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Silva TC, Aidar FJ, Zanona ADF, Matos DG, Pereira DD, Rezende PEN, Ferreira ARP, Junior HA, dos Santos JL, Silva DDS, Barbosa FDS, Thuany M, de Souza RF. The Acute Effect of Hyperoxia on Onset of Blood Lactate Accumulation (OBLA) and Performance in Female Runners during the Maximal Treadmill Test. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2021; 18:ijerph18094546. [PMID: 33922940 PMCID: PMC8123303 DOI: 10.3390/ijerph18094546] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/05/2021] [Revised: 04/21/2021] [Accepted: 04/23/2021] [Indexed: 11/30/2022]
Abstract
The objective of this study was to analyze the acute effect of hyperoxia during the maximal treadmill test (MTT) of runners. Participants included 10 female street runners who performed the MTT under two different conditions: hyperoxia (HYPX), inhaling oxygen (60% O2) every 3 min; and normoxia (NORM), without additional oxygen inhalation. Both groups performed the MTT with increases in the slope of the run every 3 min until voluntary exhaustion. The variables of lactate concentration, the onset of blood lactate accumulation (OBLA), peripheral oxygen saturation (SpO2), heart rate (HR), and Borg scale were evaluated. It was verified after the comparison (HYPX vs. NORM) that stage 3 (p = 0.012, Cohen’s d = 1.76) and stage 4 (p < 0.001; Cohen’s d = 5.69) showed a reduction in lactate under the HYPX condition. OBLA under the HYPX condition was identified at a later stage than NORM. There were no differences in Borg scale, SpO2, and HR between the different conditions. It was concluded that the HYPX condition contributed to a reduction in lactate concentration and delayed OBLA in runners.
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Affiliation(s)
- Thays C. Silva
- Department of Physical Education, Federal University of Sergipe (UFS), São Cristóvão, Sergipe 49100-000, Brazil; (T.C.S.); (F.J.A.); (P.E.N.R.); (D.d.S.S.)
| | - Felipe J. Aidar
- Department of Physical Education, Federal University of Sergipe (UFS), São Cristóvão, Sergipe 49100-000, Brazil; (T.C.S.); (F.J.A.); (P.E.N.R.); (D.d.S.S.)
- Group of Studies and Research of Performance, Sport, Health and Paralympic Sports (GEPEPS), Federal University of Sergipe (UFS), São Cristóvão, Sergipe 49100-000, Brazil; (D.G.M.); (D.D.P.)
- Post-Graduation Program of Physical Education, Federal University of Sergipe (UFS), São Cristóvão, Sergipe 49100-000, Brazil; (J.L.d.S.); (M.T.)
| | | | - Dihogo Gama Matos
- Group of Studies and Research of Performance, Sport, Health and Paralympic Sports (GEPEPS), Federal University of Sergipe (UFS), São Cristóvão, Sergipe 49100-000, Brazil; (D.G.M.); (D.D.P.)
| | - Danielle D. Pereira
- Group of Studies and Research of Performance, Sport, Health and Paralympic Sports (GEPEPS), Federal University of Sergipe (UFS), São Cristóvão, Sergipe 49100-000, Brazil; (D.G.M.); (D.D.P.)
- Department of Physiology and Pharmacology, Federal University of Pernambuco, Recife, Pernambuco 50670-901, Brazil
| | - Paulo Emmanuel Nunes Rezende
- Department of Physical Education, Federal University of Sergipe (UFS), São Cristóvão, Sergipe 49100-000, Brazil; (T.C.S.); (F.J.A.); (P.E.N.R.); (D.d.S.S.)
| | | | - Heleno Almeida Junior
- Post Graduate Program in Physiology Sciences, Department of Physiology, Federal University of Sergi, pe—UFS, São Cristóvão 49100-000, Brazil;
| | - Jymmys Lopes dos Santos
- Post-Graduation Program of Physical Education, Federal University of Sergipe (UFS), São Cristóvão, Sergipe 49100-000, Brazil; (J.L.d.S.); (M.T.)
| | - Devisson dos Santos Silva
- Department of Physical Education, Federal University of Sergipe (UFS), São Cristóvão, Sergipe 49100-000, Brazil; (T.C.S.); (F.J.A.); (P.E.N.R.); (D.d.S.S.)
- Group of Studies and Research of Performance, Sport, Health and Paralympic Sports (GEPEPS), Federal University of Sergipe (UFS), São Cristóvão, Sergipe 49100-000, Brazil; (D.G.M.); (D.D.P.)
- Post-Graduation Program of Physical Education, Federal University of Sergipe (UFS), São Cristóvão, Sergipe 49100-000, Brazil; (J.L.d.S.); (M.T.)
| | | | - Mabliny Thuany
- Post-Graduation Program of Physical Education, Federal University of Sergipe (UFS), São Cristóvão, Sergipe 49100-000, Brazil; (J.L.d.S.); (M.T.)
| | - Raphael F. de Souza
- Department of Physical Education, Federal University of Sergipe (UFS), São Cristóvão, Sergipe 49100-000, Brazil; (T.C.S.); (F.J.A.); (P.E.N.R.); (D.d.S.S.)
- Group of Studies and Research of Performance, Sport, Health and Paralympic Sports (GEPEPS), Federal University of Sergipe (UFS), São Cristóvão, Sergipe 49100-000, Brazil; (D.G.M.); (D.D.P.)
- Post-Graduation Program of Physical Education, Federal University of Sergipe (UFS), São Cristóvão, Sergipe 49100-000, Brazil; (J.L.d.S.); (M.T.)
- Correspondence: ; Tel.: +55-79-3194-6537
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21
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García I, Drobnic F, Pons V, Viscor G. Swimming exercise transiently decrease lung diffusing capacity in elite swimmers. J Sports Med Phys Fitness 2020; 61:666-672. [PMID: 33146491 DOI: 10.23736/s0022-4707.20.11302-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
BACKGROUND Swimmers have larger lungs and a higher diffusion capacity than other athletes, but it remains unknown whether swimming exercise changes lung diffusing properties. This study aimed to evaluate modifications in pulmonary alveolar-capillary diffusion after swimming exercise. METHODS The participants were 21 elite level swimmers, including 7 females and 14 males, with a training volume of 45-70 kilometers of swimming per week. The single-breath method was used to measure the lung diffusing capacity for carbon monoxide (DLCO and the transfer coefficient of the lungs for carbon monoxide (K<inf>CO</inf>) before and after 10 training sessions over 4 weeks along 207 pre- to postevaluations. RESULTS Swimming training consistently decreased lung diffusion capacity during the follow-up period, both DL<inf>CO</inf> (44.4±8.1 to 43.3±8.9 mL·min-1·mmHg-1, P=0.047, ŋ2<inf>p</inf>=0.55) and K<inf>CO</inf> (5.92±0.79 to 5.70±0.81 mL·min-1·mmHg-1·L-1, P=0.003, ŋ2<inf>p</inf>=0.75). CONCLUSIONS Elite swimmers experience a subclinical impairment in lung diffusing capacity after swimming exercise, but the stress caused by swimming on the lungs and the acute reduction in DL<inf>CO</inf> does not lead to physiological dysfunction.
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Affiliation(s)
- Iker García
- Section of Physiology, Department of Cellular Biology, Physiology and Immunology, Faculty of Biology, University of Barcelona, Barcelona, Spain - .,Department pf Physiology and Nutrition, Centre d'Alt Rendiment (CAR), Barcelona, Spain -
| | | | - Victoria Pons
- Department pf Physiology and Nutrition, Centre d'Alt Rendiment (CAR), Barcelona, Spain
| | - Ginés Viscor
- Section of Physiology, Department of Cellular Biology, Physiology and Immunology, Faculty of Biology, University of Barcelona, Barcelona, Spain
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22
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Ansdell P, Thomas K, Hicks KM, Hunter SK, Howatson G, Goodall S. Physiological sex differences affect the integrative response to exercise: acute and chronic implications. Exp Physiol 2020; 105:2007-2021. [PMID: 33002256 DOI: 10.1113/ep088548] [Citation(s) in RCA: 143] [Impact Index Per Article: 35.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2020] [Revised: 09/24/2020] [Accepted: 09/28/2020] [Indexed: 12/13/2022]
Abstract
NEW FINDINGS What is the topic of this review? We review sex differences within physiological systems implicated in exercise performance; specifically, how they integrate to determine metabolic thresholds and fatigability. Thereafter, we discuss the implications that these sex differences might have for long-term adaptation to exercise. What advances does it highlight? The review collates evidence from recent physiological studies that have investigated sex as a biological variable, demonstrating that the physiological response to equivalent 'dosages' of exercise is not the same in males and females; thus, highlighting the need to research diversity in physiological responses to interventions. ABSTRACT The anatomical and physiological differences between males and females are thought to determine differences in the limits of human performance. The notion of studying sex as a biological variable has recently been emphasized in the biosciences as a vital step in enhancing human health. In this review, we contend that the effects of biological sex on acute and chronic responses must be studied and accounted for when prescribing aerobic exercise, much like any intervention targeting the optimization of physiological function. Emerging evidence suggests that the response of physiological systems to exercise differs between males and females, potentially mediating the beneficial effects in healthy and clinical populations. We highlight evidence that integrative metabolic thresholds during exercise are influenced by phenotypical sex differences throughout many physiological systems. Furthermore, we discuss evidence that female skeletal muscle is more resistant to fatigue elicited by equivalent dosages of high-intensity exercise. How the different acute responses affect the long-term trainability of males and females is considered, with discussion about tailoring exercise to the characteristics of the individual presented within the context of biological sex. Finally, we highlight the influence of endogenous and exogenous sex hormones on physiological responses to exercise in females. Sex is one of many mediating influences on the outcomes of exercise, and with careful experimental designs, physiologists can advance the collective understanding of diversity in physiology and optimize outcomes for both sexes.
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Affiliation(s)
- Paul Ansdell
- Faculty of Health and Life Sciences, Northumbria University, Newcastle upon Tyne, UK
| | - Kevin Thomas
- Faculty of Health and Life Sciences, Northumbria University, Newcastle upon Tyne, UK
| | - Kirsty M Hicks
- Faculty of Health and Life Sciences, Northumbria University, Newcastle upon Tyne, UK
| | - Sandra K Hunter
- Department of Physical Therapy, Marquette University, Milwaukee, WI, USA
| | - Glyn Howatson
- Faculty of Health and Life Sciences, Northumbria University, Newcastle upon Tyne, UK.,Water Research Group, School of Environmental Sciences and Development, North-West University, Potchefstroom, South Africa
| | - Stuart Goodall
- Faculty of Health and Life Sciences, Northumbria University, Newcastle upon Tyne, UK
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23
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Ansdell P, Škarabot J, Atkinson E, Corden S, Tygart A, Hicks KM, Thomas K, Hunter SK, Howatson G, Goodall S. Sex differences in fatigability following exercise normalised to the power-duration relationship. J Physiol 2020; 598:5717-5737. [PMID: 32964441 DOI: 10.1113/jp280031] [Citation(s) in RCA: 40] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2020] [Accepted: 09/07/2020] [Indexed: 01/24/2023] Open
Abstract
KEY POINTS Knee-extensors demonstrate greater fatigue resistance in females compared to males during single-limb and whole-body exercise. For single-limb exercise, the intensity-duration relationship is different between sexes, with females sustaining a greater relative intensity of exercise. This study established the power-duration relationship during cycling, then assessed fatigability during critical power-matched exercise within the heavy and severe intensity domains. When critical power and the curvature constant were expressed relative to maximal ramp test power, no sex difference was observed. No sex difference in time to task failure was observed in either trial. During heavy and severe intensity cycling, females experienced lesser muscle de-oxygenation. Following both trials, females experienced lesser reductions in knee-extensor contractile function, and following heavy intensity exercise, females experienced less reduction in voluntary activation. These data demonstrate that whilst the relative power-duration relationship is not different between males and females, the mechanisms of fatigability during critical power-matched exercise are mediated by sex. ABSTRACT Due to morphological differences, females demonstrate greater fatigue resistance of locomotor muscle during single-limb and whole-body exercise modalities. Whilst females sustain a greater relative intensity of single-limb, isometric exercise than males, limited investigation has been performed during whole-body exercise. Accordingly, this study established the power-duration relationship during cycling in 18 trained participants (eight females). Subsequently, constant-load exercise was performed at critical power (CP)-matched intensities within the heavy and severe domains, with the mechanisms of fatigability assessed via non-invasive neurostimulation, near-infrared spectroscopy and pulmonary gas exchange during and following exercise. Relative CP (72 ± 5 vs. 74 ± 2% Pmax , P = 0.210) and curvature constant (51 ± 11 vs. 52 ± 10 J Pmax -1 , P = 0.733) of the power-duration relationship were similar between males and females. Subsequent heavy (P = 0.758) and severe intensity (P = 0.645) exercise time to task failures were not different between sexes. However, females experienced lesser reductions in contractile function at task failure (P ≤ 0.020), and greater vastus lateralis oxygenation (P ≤ 0.039) during both trials. Reductions in voluntary activation occurred following both trials (P < 0.001), but were less in females following the heavy trial (P = 0.036). Furthermore, during the heavy intensity trial only, corticospinal excitability was reduced at the cortical (P = 0.020) and spinal (P = 0.036) levels, but these reductions were not sex-dependent. Other than a lower respiratory exchange ratio in the heavy trial for females (P = 0.039), no gas exchange variables differed between sexes (P ≥ 0.052). Collectively, these data demonstrate that whilst the relative power-duration relationship is not different between males and females, the mechanisms of fatigability during CP-matched exercise above and below CP are mediated by sex.
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Affiliation(s)
- Paul Ansdell
- Faculty of Health and Life Sciences, Northumbria University, Newcastle upon Tyne, UK
| | - Jakob Škarabot
- Faculty of Health and Life Sciences, Northumbria University, Newcastle upon Tyne, UK.,School of Sport, Exercise and Health Sciences, Loughborough University, Loughborough, UK
| | - Elliott Atkinson
- Faculty of Health and Life Sciences, Northumbria University, Newcastle upon Tyne, UK
| | - Sarah Corden
- Faculty of Health and Life Sciences, Northumbria University, Newcastle upon Tyne, UK
| | - Amber Tygart
- Faculty of Health and Life Sciences, Northumbria University, Newcastle upon Tyne, UK
| | - Kirsty M Hicks
- Faculty of Health and Life Sciences, Northumbria University, Newcastle upon Tyne, UK
| | - Kevin Thomas
- Faculty of Health and Life Sciences, Northumbria University, Newcastle upon Tyne, UK
| | - Sandra K Hunter
- Department of Physical Therapy, Marquette University, Milwaukee, WI, USA
| | - Glyn Howatson
- Faculty of Health and Life Sciences, Northumbria University, Newcastle upon Tyne, UK.,Water Research Group, School of Environmental Sciences and Development, North-West University, Potchefstroom, South Africa
| | - Stuart Goodall
- Faculty of Health and Life Sciences, Northumbria University, Newcastle upon Tyne, UK
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Granger EA, Cooper TK, Hopkins SR, McKenzie DC, Dominelli P. Peripheral chemoresponsiveness during exercise in male athletes with exercise-induced arterial hypoxaemia. Exp Physiol 2020; 105:1960-1970. [PMID: 32857874 DOI: 10.1113/ep088639] [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: 04/27/2020] [Accepted: 08/24/2020] [Indexed: 01/10/2023]
Abstract
NEW FINDINGS What is the central question of this study? Do highly trained male endurance athletes who develop exercise-induced arterial hypoxaemia (EIAH) demonstrate reduced peripheral chemoresponsiveness during exercise? What is the main finding and its importance? Those with the lowest arterial saturation during exercise have a smaller ventilatory response to hypercapnia during exercise. There was no significant relationship between the hyperoxic ventilatory response and EIAH. The findings suggest that peripheral chemoresponsiveness to hypercapnia during exercise could play a role in the development of EIAH. The findings improve our understanding of the mechanisms that contribute to EIAH. ABSTRACT Exercise-induced arterial hypoxaemia (EIAH) is characterized by a decrease in arterial oxygen tension and/or saturation during whole-body exercise, which may in part result from inadequate alveolar ventilation. However, the role of peripheral chemoresponsiveness in the development of EIAH is not well established. We hypothesized that those with the most severe EIAH would have an attenuated ventilatory response to hyperoxia and hypercapnia during exercise. To evaluate this, on separate days, we measured ventilatory sensitivity to hyperoxia and separately hypercapnia at rest and during three different exercise intensities (25, 50% of V ̇ O 2 max and ventilatory threshold (∼67% of V ̇ O 2 max )) in 12 males cyclists ( V ̇ O 2 max = 66.6 ± 4.7 ml kg-1 min-1 ). Subjects were divided into two groups based on their end-exercise arterial oxygen saturation (ear oximetry, S p O 2 ): a normal oxyhaemoglobin saturation group (NOS, S p O 2 = 93.4 ± 0.4%, n = 5) and a low oxyhaemoglobin saturation group (LOS, S p O 2 = 89.9 ± 0.9%, n = 7). There was no difference in V ̇ O 2 max (66.4 ± 2.9 vs. 66.8 ± 6.0 ml kg-1 min-1 , respectively, P = 0.9), peak ventilation during maximal exercise (182 ± 15 vs. 197 ± 32 l min-1 , respectively, P = 0.36) or ventilatory response to hyperoxia (P = 0.98) at any exercise intensity between NOS and LOS groups. However, those in the LOS group had a significantly lower ventilatory response to hypercapnia (P = 0.004, (η2 = 0.18). There was also a significant relationship between the mean hypercapnic response and end-exercise S p O 2 (r = 0.75, P = 0.009) but not between the mean hyperoxic response and end-exercise S p O 2 (r = 0.21, P = 0.51). A blunted hypercapnic ventilatory response may contribute to EIAH in highly trained men due to a failure to increase ventilation sufficiently to offset exercise-induced gas exchange impairments.
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Affiliation(s)
- Emily A Granger
- Department of Kinesiology, University of Waterloo, Waterloo, Ontario, Canada
| | - Trevor K Cooper
- School of Kinesiology and Division of Sports Medicine, University of British Columbia, Vancouver, British Columbia, Canada
| | - Susan R Hopkins
- Departments of Medicine and Radiology, University of California, San Diego, CA, USA
| | - Donald C McKenzie
- School of Kinesiology and Division of Sports Medicine, University of British Columbia, Vancouver, British Columbia, Canada
| | - Paolo Dominelli
- Department of Kinesiology, University of Waterloo, Waterloo, Ontario, Canada
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25
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Dempsey JA, La Gerche A, Hull JH. Is the healthy respiratory system built just right, overbuilt, or underbuilt to meet the demands imposed by exercise? J Appl Physiol (1985) 2020; 129:1235-1256. [PMID: 32790594 DOI: 10.1152/japplphysiol.00444.2020] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
In the healthy, untrained young adult, a case is made for a respiratory system (airways, pulmonary vasculature, lung parenchyma, respiratory muscles, and neural ventilatory control system) that is near ideally designed to ensure a highly efficient, homeostatic response to exercise of varying intensities and durations. Our aim was then to consider circumstances in which the intra/extrathoracic airways, pulmonary vasculature, respiratory muscles, and/or blood-gas distribution are underbuilt or inadequately regulated relative to the demands imposed by the cardiovascular system. In these instances, the respiratory system presents a significant limitation to O2 transport and contributes to the occurrence of locomotor muscle fatigue, inhibition of central locomotor output, and exercise performance. Most prominent in these examples of an "underbuilt" respiratory system are highly trained endurance athletes, with additional influences of sex, aging, hypoxic environments, and the highly inbred equine. We summarize by evaluating the relative influences of these respiratory system limitations on exercise performance and their impact on pathophysiology and provide recommendations for future investigation.
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Affiliation(s)
- Jerome A Dempsey
- John Robert Sutton Professor of Population Health Sciences, John Rankin Laboratory of Pulmonary Medicine, University of Wisconsin-Madison, Madison, Wisconsin
| | - Andre La Gerche
- Clinical Research Domain, Baker Heart and Diabetes Institute, Melbourne, Australia.,National Center for Sports Cardiology, St. Vincent's Hospital, Melbourne, Fitzroy, Australia
| | - James H Hull
- Department of Respiratory Medicine, Royal Brompton Hospital, London, United Kingdom.,Institute of Sport, Exercise and Health (ISEH), University College London, United Kingdom
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26
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Dominelli PB, Molgat-Seon Y, Sheel AW. Sex Differences in the Pulmonary System Influence the Integrative Response to Exercise. Exerc Sport Sci Rev 2020; 47:142-150. [PMID: 30817330 DOI: 10.1249/jes.0000000000000188] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Healthy women have proportionally smaller lungs and airways compared with height-matched men. These anatomical sex-based differences result in greater mechanical ventilatory constraints and may influence the integrative response to exercise. Our review will examine this hypothesis in healthy humans in the context of dynamic whole-body exercise.
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Affiliation(s)
- Paolo B Dominelli
- Department of Anesthesia, Mayo Clinic, Rochester, MN.,Department of Kinesiology, University of Waterloo, Waterloo, ON, Canada
| | - Yannick Molgat-Seon
- Centre for Heart and Lung Innovation, St. Paul's Hospital.,Department of Physical Therapy, Faculty of Medicine, and
| | - A William Sheel
- School of Kinesiology, Faculty of Education, University of British Columbia, Vancouver, BC, Canada
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27
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Riganas C, Papadopoulou Z, Margaritelis NV, Christoulas K, Vrabas IS. Inspiratory muscle training effects on oxygen saturation and performance in hypoxemic rowers: Effect of sex. J Sports Sci 2019; 37:2513-2521. [DOI: 10.1080/02640414.2019.1646582] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Affiliation(s)
- Christos Riganas
- Laboratory of Exercise Physiology and Biochemistry, Department of Physical Education and Sports Science at Serres, Aristotle University of Thessaloniki, Serres, Greece
- Ergophysiology Laboratory, Department of Physical Education and Sports Science, Aristotle University of Thessaloniki, Thessaloniki, Greece
| | - Zacharoula Papadopoulou
- Laboratory of Exercise Physiology and Biochemistry, Department of Physical Education and Sports Science at Serres, Aristotle University of Thessaloniki, Serres, Greece
- Ergophysiology Laboratory, Department of Physical Education and Sports Science, Aristotle University of Thessaloniki, Thessaloniki, Greece
| | - Nikos V. Margaritelis
- Laboratory of Exercise Physiology and Biochemistry, Department of Physical Education and Sports Science at Serres, Aristotle University of Thessaloniki, Serres, Greece
- Intensive Care Unit, 424 General Military Hospital of Thessaloniki, Thessaloniki, Greece
| | - Kosmas Christoulas
- Ergophysiology Laboratory, Department of Physical Education and Sports Science, Aristotle University of Thessaloniki, Thessaloniki, Greece
| | - Ioannis S. Vrabas
- Laboratory of Exercise Physiology and Biochemistry, Department of Physical Education and Sports Science at Serres, Aristotle University of Thessaloniki, Serres, Greece
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28
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Horiuchi M, Kirihara Y, Fukuoka Y, Pontzer H. Sex differences in respiratory and circulatory cost during hypoxic walking: potential impact on oxygen saturation. Sci Rep 2019; 9:9550. [PMID: 31266961 PMCID: PMC6606641 DOI: 10.1038/s41598-019-44844-6] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2018] [Accepted: 05/23/2019] [Indexed: 11/09/2022] Open
Abstract
Energy expenditure (EE) during treadmill walking under normal conditions (normobaric normoxia, 21% O2) and moderate hypoxia (13% O2) was measured. Ten healthy young men and ten healthy young women walked on a level (0°) gradient a range of speeds (0.67–1.67 m s−1). During walking, there were no significant differences in reductions in arterial oxygen saturation (SpO2) between the sexes. The hypoxia-induced increase in EE, heart rate (HR [bpm]) and ventilation (\documentclass[12pt]{minimal}
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\begin{document}$${\dot{{\rm{V}}}}_{{\rm{E}}}$$\end{document}V˙E [L min−1]) were calculated. Using a multivariate model that combined EE, \documentclass[12pt]{minimal}
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\begin{document}$${\dot{{\rm{V}}}}_{{\rm{E}}}$$\end{document}V˙E, and HR to predict ΔSpO2 (hypoxia-induced reduction), a very strong fit model both for men (r2 = 0.900, P < 0.001) and for women was obtained (r2 = 0.957, P < 0.001). The contributions of EE, VE, and HR to ΔSpO2 were markedly different between men and women. \documentclass[12pt]{minimal}
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\begin{document}$${\dot{{\rm{V}}}}_{{\rm{E}}}$$\end{document}V˙E and EE had a stronger effect on ΔSpO2 in women (\documentclass[12pt]{minimal}
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\begin{document}$${\dot{{\rm{V}}}}_{{\rm{E}}}$$\end{document}V˙E: 4.1% in women vs. 1.7% in men; EE: 28.1% in women vs. 15.8% in men), while HR had a greater effect in men (82.5% in men and 67.9% in women). These findings suggested that high-altitude adaptation in response to hypoxemia has different underlying mechanisms between men and women. These results can help to explain how to adapt high-altitude for men and women, respectively.
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Affiliation(s)
- Masahiro Horiuchi
- Division of Human Environmental Science, Mt. Fuji Research Institute, Kamiyoshida 5597-1, Fujiyoshida-city, Yamanashi, 4030005, Japan.
| | - Yoko Kirihara
- Division of Human Environmental Science, Mt. Fuji Research Institute, Kamiyoshida 5597-1, Fujiyoshida-city, Yamanashi, 4030005, Japan
| | - Yoshiyuki Fukuoka
- Faculty of Health and Sports Science, Doshisha University, Tatara 1-3, Kyotanabe, Kyoto, 6100394, Japan
| | - Herman Pontzer
- Department of Evolutionary Anthropology, Duke University, Biological Sciences Building Campus Box 90383, Durham, NC, 27708-9976, USA
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29
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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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30
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García-Martínez D, Bastir M, Torres-Tamayo N, O'Higgins P, Torres-Sánchez I, García-Río F, Heuzé Y. Three-dimensional analysis of sexual dimorphism in ribcage kinematics of modern humans. AMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY 2019; 169:348-355. [PMID: 30934120 DOI: 10.1002/ajpa.23829] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/05/2018] [Revised: 03/13/2019] [Accepted: 03/17/2019] [Indexed: 11/10/2022]
Abstract
OBJECTIVES Sexual dimorphism is an important biological factor underlying morphological variation in the human skeleton. Previous research found sex-related differences in the static ribcage, with males having more horizontally oriented ribs and a wider lower ribcage than females. Furthermore, a recent study found sex-related differences in the kinematics of the human lungs, with cranio-caudal movements of the caudal part of the lungs accounting for most of the differences between sexes. However, these movements cannot be quantified in the skeletal ribcage, so we do not know if the differences observed in the lungs are also reflected in sex differences in the motion of the skeletal thorax. MATERIALS AND METHODS To address this issue, we quantified the morphological variation of 42 contemporary human ribcages (sex-balanced) in both maximal inspiration and expiration using 526 landmarks and semilandmarks. Thoracic centroid size differences between sexes were assessed using a t test, and shape differences were assessed using Procrustes shape coordinates, through mean comparisons and dummy regressions of shape on kinematic status. A principal components analysis was used to explore the full range of morphological variation. RESULTS Our results show significant size differences between males and females both in inspiration and expiration (p < .01) as well as significant shape differences, with males deforming more than females during inspiration, especially in the mediolateral dimension of the lower ribcage. Finally, dummy regressions of shape on kinematic status showed a small but statistically significant difference in vectors of breathing kinematics between males and females (14.78°; p < .01). DISCUSSION We support that sex-related differences in skeletal ribcage kinematics are discernible, even when soft tissues are not analyzed. We hypothesize that this differential breathing pattern is primarily a result of more pronounced diaphragmatic breathing in males, which might relate to differences in body composition, metabolism, and ultimately greater oxygen demand in males compared to females. Future research should further explore the links between ribcage morphological variation and basal metabolic rate.
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Affiliation(s)
- Daniel García-Martínez
- University of Bordeaux, CNRS, MCC, PACEA, Pessac, France.,Departamento de Paleobiología, Museo Nacional de Ciencias Naturales (CSIC), Madrid, Spain.,Centro de Estudios del Campo de Montiel (CECM), Ciudad Real, Castilla-La Mancha, Spain
| | - Markus Bastir
- Departamento de Paleobiología, Museo Nacional de Ciencias Naturales (CSIC), Madrid, Spain
| | - Nicole Torres-Tamayo
- Departamento de Paleobiología, Museo Nacional de Ciencias Naturales (CSIC), Madrid, Spain
| | - Paul O'Higgins
- Department of Archaeology and Hull York Medical School, the University of York, York, United Kingdom
| | | | - Francisco García-Río
- Hospital La Paz Institute for Health Research (IdiPAZ), Madrid, Spain.,Centro de Investigación Biomédica en Red en Enfermedades Respiratorias (CIBERES), Madrid, Spain
| | - Yann Heuzé
- Universite de Bordeaux, CNRS, MCC, De la Prehistoire a l'Actuel: Culture, Environnement et Anthropologie, (PACEA), Pessac, France
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31
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Ventilatory responses in males and females during graded exercise with and without thoracic load carriage. Eur J Appl Physiol 2018; 119:441-453. [DOI: 10.1007/s00421-018-4042-5] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2018] [Accepted: 11/26/2018] [Indexed: 12/15/2022]
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32
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Molgat-Seon Y, Peters CM, Sheel AW. Sex-differences in the human respiratory system and their impact on resting pulmonary function and the integrative response to exercise. CURRENT OPINION IN PHYSIOLOGY 2018. [DOI: 10.1016/j.cophys.2018.03.007] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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33
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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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34
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Abel A, Baron B, Grappe F, Francaux M. Effect of environmental feedbacks on pacing strategy and affective load during a self-paced 30 min cycling time trial. J Sports Sci 2018; 37:291-297. [PMID: 30020858 DOI: 10.1080/02640414.2018.1497934] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Abstract
The purpose of this study was to analyze the pacing strategy and its affective consequences during self-paced cycling time trials (TT) performed at different severity of hypoxia. Eight competitive cyclists performed five 30 min self-paced TTs at their best performance in the following conditions: 1) normobaric normoxia (NNSL); 2) normobaric hypoxia under two simulated altitudes: 2000 m (NH2000) and 3500 m (NH3500) and 3) normobaric hypoxia but the cyclists were deceived and thought to be at sea level for 2000 m (DecNH2000) and 3500 m (DecNH3500). Power Output (PO), oxygen uptake (VO2), and blood lactate concentration ([La]) were recorded to assess exercise intensity and physiological adaptations. The rate of perceived exertion (RPE) and pleasure were measured with a CR10 Borg scale to evaluate the affective load (AL). PO and VO2 decreased with the severity of hypoxia but no significantly difference on performance was measured between deceived and real conditions, except for pacing strategy. The started intensity depends on the exercise expectations, but PO was rapidly adjusted with the physiological constraints and the rate of increase of RPE. Finally, AL did not reach maximal values so that the athletes sustained a physiological and emotional reserve to perform a final spurt.
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Affiliation(s)
- Alexandre Abel
- a Health and Sports Department , University of Franche Comte , Besançon , France.,b Institute of Neuroscience, UCLouvain , Louvain-la-Neuve , Belgium
| | - Bertrand Baron
- c Université de La Réunion , UFR des Sciences et Techniques des Activités Physiques et Sportives (STAPS) , Le Tampon , France
| | - Frédéric Grappe
- d Université de Franche Comté , UFR des Sciences et Techniques des Activités Physiques et Sportives (STAPS) , Besançon , France
| | - Marc Francaux
- b Institute of Neuroscience, UCLouvain , Louvain-la-Neuve , Belgium
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Abstract
Men Are from Mars, Women Are from Venus. John Gray used this provocative title for his book to describe the fundamental psychological differences between the sexes. Many other controlled studies and brain scans demonstrate that men and women are physically and mentally different. The purpose of this physiology masterclass is to illustrate how sex-related differences are present in respiratory function and their possible clinical implications. An overview of sex-related differences in respiratory function and their possible clinical implicationshttp://ow.ly/106m30jqOSW
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Affiliation(s)
- Antonella LoMauro
- Dipartimento di Elettronica, Informazione e Bioingegneria, Politecnico di Milano, Milan, Italy
| | - Andrea Aliverti
- Dipartimento di Elettronica, Informazione e Bioingegneria, Politecnico di Milano, Milan, Italy
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36
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Botek M, Krejčí J, McKune A. Sex Differences in Autonomic Cardiac Control and Oxygen Saturation Response to Short-Term Normobaric Hypoxia and Following Recovery: Effect of Aerobic Fitness. Front Endocrinol (Lausanne) 2018; 9:697. [PMID: 30532736 PMCID: PMC6265316 DOI: 10.3389/fendo.2018.00697] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/05/2018] [Accepted: 11/05/2018] [Indexed: 01/06/2023] Open
Abstract
Introduction: The main aims of this study were to investigate autonomic nervous system (ANS) and arterial oxygen saturation (SpO2) responses to simulated altitude in males and females, and to determine the association between maximal oxygen uptake (VO2max) and these responses. Materials and Methods: Heart rate variability (HRV) and SpO2 were monitored in a resting supine position during Preliminary (6 min normoxia), Hypoxia (10 min, fraction of inspired oxygen (FiO2) of 9.6%, simulated altitude ~6,200 m) and Recovery (6 min normoxia) phases in 28 males (age 23.7 ± 1.7 years, normoxic VO2max 59.0 ± 7.8 ml.kg-1.min-1, body mass index (BMI) 24.2 ± 2.1 kg.m-2) and 30 females (age 23.8 ± 1.8 years, VO2max 45.1 ± 8.7 ml.kg-1.min-1, BMI 21.8 ± 3.0 kg.m-2). Spectral analysis of HRV quantified the ANS activity by means of low frequency (LF, 0.05-0.15 Hz) and high frequency (HF, 0.15-0.50 Hz) power, transformed by natural logarithm (Ln). Time domain analysis incorporated the square root of the mean of the squares of the successive differences (rMSSD). Results: There were no significant differences in SpO2 level during hypoxia between the males (71.9 ± 7.5%) and females (70.8 ± 7.1%). Vagally-related HRV variables (Ln HF and Ln rMSSD) exhibited no significant differences between sexes across each phase. However, while the sexes demonstrated similar Ln LF/HF values during the Preliminary phase, the males (0.5 ± 1.3) had a relatively higher (p = 0.001) sympathetic activity compared to females (-0.6 ± 1.4) during the Hypoxia phase. Oxygen desaturation during resting hypoxia was significantly correlated with VO2max in males (r = -0.45, p = 0.017) but not in females (r = 0.01, p = 0.952) and difference between regression lines were significant (p = 0.024). Conclusions: Despite similar oxygen desaturation levels, males exhibited a relatively higher sympathetic responses to hypoxia exposure compared with females. In addition, the SpO2 response to resting hypoxia exposure was related to maximal aerobic capacity in males but not females.
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Affiliation(s)
- Michal Botek
- Department of Natural Sciences in Kinanthropology, Faculty of Physical Culture, Palacký University Olomouc, Olomouc, Czechia
| | - Jakub Krejčí
- Department of Natural Sciences in Kinanthropology, Faculty of Physical Culture, Palacký University Olomouc, Olomouc, Czechia
- *Correspondence: Jakub Krejčí
| | - Andrew McKune
- Discipline of Sport and Exercise Science, School of Rehabilitation and Exercise Sciences, Research Institute for Sport and Exercise Science, University of Canberra, Canberra, ACT, Australia
- Discipline of Biokinetics, Exercise and Leisure Sciences, School of Health Sciences, University of KwaZulu-Natal, Durban, South Africa
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Affiliation(s)
- I Mark Olfert
- Division of Exercise Physiology. .,Center for Cardiovascular & Respiratory Sciences. .,West Virginia Clinical and Translational Science Institute, West Virginia University School of Medicine, 1 Medical Center Drive, PO Box 9105, Morgantown, WV, USA.
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Constantini K, Tanner DA, Gavin TP, Harms CA, Stager JM, Chapman RF. Prevalence of Exercise-Induced Arterial Hypoxemia in Distance Runners at Sea Level. Med Sci Sports Exerc 2017; 49:948-954. [PMID: 28009787 DOI: 10.1249/mss.0000000000001193] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
PURPOSE It has been reported that ~50% of endurance-trained men demonstrate exercise-induced arterial hypoxemia (EIAH) during heavy exercise. However, this often-cited prevalence rate comes from a single study using a cohort of 25 highly trained men who completed maximal cycle ergometry. As arterial oxyhemoglobin saturation (SpO2) during maximal exercise is reported to be significantly lower during treadmill versus cycle ergometry in the same subjects, we hypothesized that the prevalence of EIAH would be greater than previously reported (and commonly referenced) in a larger cohort of highly endurance-trained men during maximal treadmill running. METHODS Data from 124 highly trained male distance runners (V˙O2max range = 60.3-84.7 mL·kg·min) were retrospectively examined from previously published studies completed in the Indiana University Human Performance Laboratory. Subjects completed a constant speed, progressive-grade treadmill exercise test to volitional exhaustion, and arterial oxyhemoglobin saturation (SaO2ear) in all subjects was estimated using the same oximeter (Hewlett Packard 47201A). RESULTS Using similar inclusion criteria as previously published for highly trained (V˙O2max > 68 mL·kg·min) and for EIAH (SaO2ear ≤ 91%), 55 of 79 subjects (70%) exhibited exercise-induced arterial desaturation. Across all 124 subjects, 104 (84%) demonstrated at least moderate EIAH (SaO2ear ≤ 93%) during maximal treadmill exercise. SaO2ear was significantly yet weakly correlated with V˙E/V˙O2 (P < 0.01, r = 0.28) and V˙E/V˙CO2 (P < 0.001, r = 0.33) but not with V˙O2max. CONCLUSION These results indicate that the prevalence of EIAH in highly trained men during maximal treadmill exercise at sea level is greater compared with previously suggested data, with exercise mode perhaps playing a factor in the number of athletes who experience EIAH.
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Affiliation(s)
- Keren Constantini
- 1HH Morris Human Performance Laboratory, Department of Kinesiology, Indiana University, Bloomington, IN; 2Department of Health and Kinesiology, Purdue University, West Lafayette, IN; and 3Department of Kinesiology, Kansas State University, Manhattan, KS
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Dominelli PB, Molgat-Seon Y, Griesdale DEG, Peters CM, Blouin JS, Sekhon M, Dominelli GS, Henderson WR, Foster GE, Romer LM, Koehle MS, Sheel AW. Exercise-induced quadriceps muscle fatigue in men and women: effects of arterial oxygen content and respiratory muscle work. J Physiol 2017; 595:5227-5244. [PMID: 28524229 DOI: 10.1113/jp274068] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2017] [Accepted: 05/16/2017] [Indexed: 11/08/2022] Open
Abstract
KEY POINTS High work of breathing and exercise-induced arterial hypoxaemia (EIAH) can decrease O2 delivery and exacerbate exercise-induced quadriceps fatigue in healthy men. Women have a higher work of breathing during exercise, dedicate a greater fraction of whole-body V̇O2 towards their respiratory muscles and develop EIAH. Despite a greater reduction in men's work of breathing, the attenuation of quadriceps fatigue was similar between the sexes. The degree of EIAH was similar between sexes, and regardless of sex, those who developed the greatest hypoxaemia during exercise demonstrated the most attenuation of quadriceps fatigue. Based on our previous finding that women have a greater relative oxygen cost of breathing, women appear to be especially susceptible to work of breathing-related changes in quadriceps muscle fatigue. ABSTRACT Reducing the work of breathing or eliminating exercise-induced arterial hypoxaemia (EIAH) during exercise decreases the severity of quadriceps fatigue in men. Women have a greater work of breathing during exercise, dedicate a greater fraction of whole-body V̇O2 towards their respiratory muscles, and demonstrate EIAH, suggesting women may be especially susceptible to quadriceps fatigue. Healthy subjects (8 male, 8 female) completed three constant load exercise tests over 4 days. During the first (control) test, subjects exercised at ∼85% of maximum while arterial blood gases and work of breathing were assessed. Subsequent constant load exercise tests were iso-time and iso-work rate, but with EIAH prevented by inspiring hyperoxic gas or work of breathing reduced via a proportional assist ventilator (PAV). Quadriceps fatigue was assessed by measuring force in response to femoral nerve stimulation. For both sexes, quadriceps force was equally reduced after the control trial (-27 ± 2% baseline) and was attenuated with hyperoxia and PAV (-18 ± 1 and -17 ± 2% baseline, P < 0.01, respectively), with no sex difference. EIAH was similar between the sexes, and regardless of sex, subjects with the lowest oxyhaemoglobin saturation during the control test had the greatest quadriceps fatigue attenuation with hyperoxia (r2 = 0.79, P < 0.0001). For the PAV trial, despite reducing the work of breathing to a greater degree in men (men: 60 ± 5, women: 75 ± 6% control, P < 0.05), the attenuation of quadriceps fatigue was similar between the sexes (36 ± 4 vs. 37 ± 7%). Owing to a greater relative V̇O2 of the respiratory muscles in women, less of a change in work of breathing is needed to reduce quadriceps fatigue.
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Affiliation(s)
- Paolo B Dominelli
- School of Kinesiology, University of British Columbia, Vancouver, BC, Canada
| | - Yannick Molgat-Seon
- School of Kinesiology, University of British Columbia, Vancouver, BC, Canada
| | - Donald E G Griesdale
- Division of Critical Care Medicine, Faculty of Medicine, University of British Columbia, Vancouver, BC, Canada
| | - Carli M Peters
- School of Kinesiology, University of British Columbia, Vancouver, BC, Canada
| | | | - Mypinder Sekhon
- Division of Critical Care Medicine, Faculty of Medicine, University of British Columbia, Vancouver, BC, Canada
| | - Giulio S Dominelli
- Division of Respiratory Medicine, University of British Columbia, Kelowna, BC, Canada
| | - William R Henderson
- Division of Critical Care Medicine, Faculty of Medicine, University of British Columbia, Vancouver, BC, Canada
| | - Glen E Foster
- Centre for Heart, Lung, and Vascular Health, School of Health and Exercise Sciences, University of British Columbia, Kelowna, BC, Canada
| | - Lee M Romer
- Centre for Human Performance, Exercise and Rehabilitation, Division of Sport, Health and Exercise Sciences, Brunel University London, Uxbridge, UK
| | - Michael S Koehle
- School of Kinesiology, University of British Columbia, Vancouver, BC, Canada
| | - A William Sheel
- School of Kinesiology, University of British Columbia, Vancouver, BC, Canada
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Joyner MJ. Physiological limits to endurance exercise performance: influence of sex. J Physiol 2017; 595:2949-2954. [PMID: 28028816 DOI: 10.1113/jp272268] [Citation(s) in RCA: 79] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2016] [Accepted: 12/16/2016] [Indexed: 11/08/2022] Open
Abstract
This brief review summarizes factors associated with elite endurance performance, trends in distance running training, and participation by men and more recently women. It is framed in the context of key ideas about the physiological determinants of endurance performance but also touches on some historical and sociological factors relevant to the overall topic. Historical trends that served to increase women's participation in elite endurance events are also discussed as is the role of increased volume and intensity of training. The rapid improvement in women's world record marathon times in the 1970s and 80s are emblematic of these trends and represent a combination of increased training volume and intensity and more competitive opportunities. This occurred as bans on participation by women in endurance events were lifted. For men these same trends evolved over a much longer time frame. The main physiological factor responsible for 10-12% slower times in women compared to men at the elite level are also considered and probably centre aroundV̇O2 max .
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Affiliation(s)
- Michael J Joyner
- Department of Anesthesiology, Mayo Clinic, Rochester, MN, 55905, USA
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DIEBEL SEBASTIANR, NEWHOUSE IAN, THOMPSON DAVIDS, JOHNSON VINEETB. The Effects of a 10-day Altitude Training Camp at 1828 Meters on Varsity Cross-Country Runners. INTERNATIONAL JOURNAL OF EXERCISE SCIENCE 2017; 10:97-107. [PMID: 28479950 PMCID: PMC5213424] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Altitude training has been shown to alter blood lactate (BL) levels due to alterations resulting from acclimatization. This study aims to estimate the impact of altitude training on BL changes immediately following an incremental treadmill test and during recovery before and after 10-day altitude training at approximately 1828 meters. Eight varsity cross-country runners performed an incremental treadmill test (ITT), pre and post-altitude training. Resting and post-warm-up BL values were recorded. During ITT, heart rate (HR), oxygen saturation (SpO2), and time to exhaustion were monitored. BL was also measured post-ITT at 0, 2, 4, 6, and 8 minutes. The average of all BL values was higher following altitude intervention (8.8 ± 4.6 mmol/L) compared to pre-intervention (7.4 ± 3.3 mmol/L). These differences were statistically significant (t(6) = -2.40, p = .026). BL immediately (0 minutes) after the ITT was higher following the altitude intervention (13.6 ± 3.6 mmol/L) compared to pre-intervention (9.7 ± 3.8 mmol/L) and was statistically significant (t(7) = -3.30, p = .006). Average HR during the ITT was lower following the altitude intervention (176.9 ± 11.1 bpm) compared to pre (187 ± 9.5 bpm), these differences were statistically significant (t(28)= 18.07, p= <.001. Time to exhaustion was longer after the intervention, however was not statistically significant p = 0.13. These findings indicate that a 10 - day altitude intervention at 1828 meters may benefit varsity cross-country runners. The higher post-exercise BL may be attributed to more anaerobic contributions. Lower HR may suggest a larger stroke volume and/or more efficient O2 carrying capacity.
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Affiliation(s)
| | - IAN NEWHOUSE
- School of Kinesiology, Lakehead University, Thunder Bay, ON, Canada
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Bouwsema MM, Tedjasaputra V, Stickland MK. Are there sex differences in the capillary blood volume and diffusing capacity response to exercise? J Appl Physiol (1985) 2016; 122:460-469. [PMID: 27932673 DOI: 10.1152/japplphysiol.00389.2016] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2016] [Revised: 12/05/2016] [Accepted: 12/05/2016] [Indexed: 11/22/2022] Open
Abstract
Previous work suggests that women may exhibit a greater respiratory limitation in exercise compared with height-matched men. Diffusion capacity (DlCO) increases with incremental exercise, and the smaller lungs of women may limit membrane diffusing capacity (Dm) and pulmonary capillary blood volume (Vc) in response to the increased oxygen demand. We hypothesized that women would have lower DlCO, DlCO relative to cardiac output (DlCO/Q̇), Dm, Vc, and pulmonary transit time, secondary to lower Vc at peak exercise. Sixteen women (112 ± 12% predicted relative V̇o2peak) and sixteen men (118 ± 22% predicted relative V̇o2peak) were matched for height and weight. Hemoglobin-corrected diffusing capacity (DlCO), Vc, and Dm were determined via the multiple-[Formula: see text] DlCO technique at rest and during incremental exercise up to 90% of V̇o2peak Both groups increased DlCO, Vc, and Dm with exercise intensity, but women had 20% lower DlCO (P < 0.001), 18% lower Vc (P = 0.002), and 22% lower Dm (P < 0.001) compared with men across all workloads, and neither group exhibited a plateau in Vc. When expressed relative to alveolar volume (Va), the between-sex difference was eliminated. The drop in DlCO/Q̇ was proportionally less in women than men, and mean pulmonary transit time did not drop below 0.3 s in either group. Women demonstrate consistently lower DlCO, Vc, and Dm compared with height-matched men during exercise; however, these differences disappear with correction for lung size. These results suggest that after differences in lung volume are accounted for there is no intrinsic sex difference in the DlCO, Vc, or Dm response to exercise.NEW & NOTEWORTHY Women demonstrate lower diffusing capacity-to-cardiac output ratio (DlCO/Q̇), pulmonary capillary blood volume (Vc), and membrane diffusing capacity (Dm) compared with height-matched men during exercise. However, these differences disappear after correction for lung size. The drop in DlCO/Q̇ was proportionally less in women, and pulmonary transit time did not drop below 0.3 s in either group. After differences in lung volume are accounted for, there is no intrinsic sex difference in DlCO, Vc, or Dm response to exercise.
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Affiliation(s)
- Melissa M Bouwsema
- Faculty of Medicine and Dentistry, University of Alberta, Edmonton, Alberta, Canada.,Faculty of Physical Education and Recreation, University of Alberta, Edmonton, Alberta, Canada; and
| | - Vincent Tedjasaputra
- Faculty of Medicine and Dentistry, University of Alberta, Edmonton, Alberta, Canada.,Faculty of Physical Education and Recreation, University of Alberta, Edmonton, Alberta, Canada; and
| | - Michael K Stickland
- Faculty of Medicine and Dentistry, University of Alberta, Edmonton, Alberta, Canada; .,G. F. MacDonald Centre for Lung Health, Covenant Health, Edmonton, Alberta, Canada
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No difference in plantar flexion maximal exercise power output between men and women. SPORT SCIENCES FOR HEALTH 2016. [DOI: 10.1007/s11332-016-0330-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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Ritti-Dias RM, Cucato GG, de Mello Franco FG, Cendoroglo MS, Nasri F, Monteiro-Costa ML, de Carvalho JAM, de Matos LDNJ. Peak expiratory flow mediates the relationship between handgrip strength and timed up and go performance in elderly women, but not men. Clinics (Sao Paulo) 2016; 71:517-20. [PMID: 27652833 PMCID: PMC5004575 DOI: 10.6061/clinics/2016(09)06] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/30/2016] [Accepted: 06/29/2016] [Indexed: 12/18/2022] Open
Abstract
OBJECTIVE The aim of the present study was to verify if there is sex difference in the associations among handgrip strength, peak expiratory flow (PEF) and timed up and go (TUG) test results. METHODS The sample included 288 consecutive elderly men (n=93) and women (n=195). Functional capacity was measured using the TUG test, and muscle strength was measured based on handgrip. Moreover, as a measure of current health status, PEF was evaluated. Linear regression procedures were performed to analyze the relationships between handgrip and both PEF and TUG test results, with adjustment for confounders, and to identify the possible mediating role of PEF in the association between handgrip strength and TUG test results. RESULTS In men, handgrip strength was associated with both PEF and TUG performance (p<0.01). After adjustment for PEF, the relationship between handgrip strength and TUG performance remained significant. In women, handgrip strength was also associated with both PEF and TUG performance (p<0.01). However, after adjustment for PEF, the relationship between handgrip strength and TUG performance was no longer significant. CONCLUSION Mobility in the elderly is sex dependent. In particular, PEF mediates the relationship between handgrip strength and TUG performance in women, but not in men.
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García-Martínez D, Torres-Tamayo N, Torres-Sanchez I, García-Río F, Bastir M. Morphological and functional implications of sexual dimorphism in the human skeletal thorax. AMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY 2016; 161:467-477. [DOI: 10.1002/ajpa.23051] [Citation(s) in RCA: 52] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/13/2016] [Revised: 05/20/2016] [Accepted: 07/01/2016] [Indexed: 01/05/2023]
Affiliation(s)
- Daniel García-Martínez
- Paleoanthropology Group; Paleobiology Department, Museo Nacional de Ciencias Naturales (MNCN-CSIC); Madrid Spain
- Biology Department; Faculty of Sciences, Universidad Autónoma De Madrid; Madrid Spain
| | - Nicole Torres-Tamayo
- Paleoanthropology Group; Paleobiology Department, Museo Nacional de Ciencias Naturales (MNCN-CSIC); Madrid Spain
| | | | - Francisco García-Río
- Hospital Universitario La Paz, Biomedical Research Institute (IdiPAZ); Madrid Spain
| | - Markus Bastir
- Paleoanthropology Group; Paleobiology Department, Museo Nacional de Ciencias Naturales (MNCN-CSIC); Madrid Spain
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Cory JM, Schaeffer MR, Wilkie SS, Ramsook AH, Puyat JH, Arbour B, Basran R, Lam M, Les C, MacDonald B, Jensen D, Guenette JA. Sex differences in the intensity and qualitative dimensions of exertional dyspnea in physically active young adults. J Appl Physiol (1985) 2015; 119:998-1006. [PMID: 26338458 DOI: 10.1152/japplphysiol.00520.2015] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2015] [Accepted: 09/02/2015] [Indexed: 02/07/2023] Open
Abstract
Understanding sex differences in the qualitative dimensions of exertional dyspnea may provide insight into why women are more affected by this symptom than men. This study explored the evolution of the qualitative dimensions of dyspnea in 70 healthy, young, physically active adults (35 M and 35 F). Participants rated the intensity of their breathing discomfort (Borg 0-10 scale) and selected phrases that best described their breathing from a standardized list (work/effort, unsatisfied inspiration, and unsatisfied expiration) throughout each stage of a symptom-limited incremental-cycle exercise test. Following exercise, participants selected phrases that described their breathing at maximal exercise from a list of 15 standardized phrases. Intensity of breathing discomfort was significantly higher in women for a given ventilation, but differences disappeared when ventilation was expressed as a percentage of maximum voluntary ventilation. The dominant qualitative descriptor in both sexes throughout exercise was increased work/effort of breathing. At peak exercise, women were significantly more likely to select the following phrases: "my breathing feels shallow," "I cannot get enough air in," "I cannot take a deep breath in," and "my breath does not go in all the way." Women adopted a more rapid and shallow breathing pattern and had significantly higher end-inspiratory lung volumes relative to total lung capacity throughout exercise relative to men. These findings suggest that men and women do not differ in their perceived quality of dyspnea during submaximal exercise, but subjective differences appear at maximal exercise and may be related, at least in part, to underlying sex differences in breathing patterns and operating lung volumes during exercise.
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Affiliation(s)
- Julia M Cory
- Centre for Heart Lung Innovation, Providence Health Care Research Institute, University of British Columbia, St. Paul's Hospital, Vancouver, British Columbia, Canada
| | - Michele R Schaeffer
- Centre for Heart Lung Innovation, Providence Health Care Research Institute, University of British Columbia, St. Paul's Hospital, Vancouver, British Columbia, Canada; Department of Physical Therapy, University of British Columbia, Vancouver, British Columbia, Canada
| | - Sabrina S Wilkie
- Centre for Heart Lung Innovation, Providence Health Care Research Institute, University of British Columbia, St. Paul's Hospital, Vancouver, British Columbia, Canada
| | - Andrew H Ramsook
- Centre for Heart Lung Innovation, Providence Health Care Research Institute, University of British Columbia, St. Paul's Hospital, Vancouver, British Columbia, Canada; Department of Physical Therapy, University of British Columbia, Vancouver, British Columbia, Canada
| | - Joseph H Puyat
- Centre for Health Evaluation and Outcome Sciences, Providence Health Care Research Institute, University of British Columbia, St. Paul's Hospital, Vancouver, British Columbia, Canada
| | - Brandon Arbour
- Department of Physical Therapy, University of British Columbia, Vancouver, British Columbia, Canada
| | - Robbi Basran
- Department of Physical Therapy, University of British Columbia, Vancouver, British Columbia, Canada
| | - Michael Lam
- Department of Physical Therapy, University of British Columbia, Vancouver, British Columbia, Canada
| | - Christian Les
- Department of Physical Therapy, University of British Columbia, Vancouver, British Columbia, Canada
| | - Benjamin MacDonald
- Department of Physical Therapy, University of British Columbia, Vancouver, British Columbia, Canada
| | - Dennis Jensen
- Department of Kinesiology and Physical Education, McGill University, Montréal, Québec, Canada
| | - Jordan A Guenette
- Centre for Heart Lung Innovation, Providence Health Care Research Institute, University of British Columbia, St. Paul's Hospital, Vancouver, British Columbia, Canada; Department of Physical Therapy, University of British Columbia, Vancouver, British Columbia, Canada;
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Abstract
We address adaptive vs. maladaptive responses to hypoxemia in healthy humans and hypoxic-tolerant species during wakefulness, sleep, and exercise. Types of hypoxemia discussed include short-term and life-long residence at high altitudes, the intermittent hypoxemia attending sleep apnea, or training regimens prescribed for endurance athletes. We propose that hypoxia presents an insult to O2 transport, which is poorly tolerated in most humans because of the physiological cost.
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Affiliation(s)
- Jerome A Dempsey
- John Rankin Laboratory of Pulmonary Medicine, School of Medicine and Public Health, University of Wisconsin, Madison, Wisconsin; Department of Population Health Sciences, School of Medicine and Public Health, University of Wisconsin, Madison, Wisconsin; and
| | - Barbara J Morgan
- John Rankin Laboratory of Pulmonary Medicine, School of Medicine and Public Health, University of Wisconsin, Madison, Wisconsin; Department of Orthopedics and Rehabilitation, School of Medicine and Public Health, University of Wisconsin, Madison, Wisconsin
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Joyner MJ, Casey DP. Regulation of increased blood flow (hyperemia) to muscles during exercise: a hierarchy of competing physiological needs. Physiol Rev 2015; 95:549-601. [PMID: 25834232 DOI: 10.1152/physrev.00035.2013] [Citation(s) in RCA: 426] [Impact Index Per Article: 47.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
This review focuses on how blood flow to contracting skeletal muscles is regulated during exercise in humans. The idea is that blood flow to the contracting muscles links oxygen in the atmosphere with the contracting muscles where it is consumed. In this context, we take a top down approach and review the basics of oxygen consumption at rest and during exercise in humans, how these values change with training, and the systemic hemodynamic adaptations that support them. We highlight the very high muscle blood flow responses to exercise discovered in the 1980s. We also discuss the vasodilating factors in the contracting muscles responsible for these very high flows. Finally, the competition between demand for blood flow by contracting muscles and maximum systemic cardiac output is discussed as a potential challenge to blood pressure regulation during heavy large muscle mass or whole body exercise in humans. At this time, no one dominant dilator mechanism accounts for exercise hyperemia. Additionally, complex interactions between the sympathetic nervous system and the microcirculation facilitate high levels of systemic oxygen extraction and permit just enough sympathetic control of blood flow to contracting muscles to regulate blood pressure during large muscle mass exercise in humans.
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Affiliation(s)
- Michael J Joyner
- Department of Anesthesiology, Mayo Clinic, Rochester, Minnesota; and Department of Physical Therapy and Rehabilitation Science, University of Iowa, Iowa City, Iowa
| | - Darren P Casey
- Department of Anesthesiology, Mayo Clinic, Rochester, Minnesota; and Department of Physical Therapy and Rehabilitation Science, University of Iowa, Iowa City, Iowa
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Dominelli PB, Render JN, Molgat-Seon Y, Foster GE, Romer LM, Sheel AW. Oxygen cost of exercise hyperpnoea is greater in women compared with men. J Physiol 2015; 593:1965-79. [PMID: 25652549 DOI: 10.1113/jphysiol.2014.285965] [Citation(s) in RCA: 97] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2014] [Accepted: 01/20/2015] [Indexed: 12/15/2022] Open
Abstract
KEY POINTS The oxygen cost of breathing represents a significant fraction of total oxygen uptake during intense exercise. At a given ventilation, women have a greater work of breathing compared with men, and because work is linearly related to oxygen uptake we hypothesized that their oxygen cost of breathing would also be greater. For a given ventilation, women had a greater absolute oxygen cost of breathing, and this represented a greater fraction of total oxygen uptake. Regardless of sex, those who developed expiratory flow limitation had a greater oxygen cost of breathing at maximal exercise. The greater oxygen cost of breathing in women indicates that a greater fraction of total oxygen uptake (and possibly cardiac output) is directed to the respiratory muscles, which may influence blood flow distribution during exercise. ABSTRACT We compared the oxygen cost of breathing (V̇O2 RM ) in healthy men and women over a wide range of exercise ventilations (V̇E). Eighteen subjects (nine women) completed 4 days of testing. First, a step-wise maximal cycle exercise test was completed for the assessment of spontaneous breathing patterns. Next, subjects were familiarized with the voluntary hyperpnoea protocol used to estimate V̇O2 RM . During the final two visits, subjects mimicked multiple times (four to six) the breathing patterns associated with five or six different exercise stages. Each trial lasted 5 min, and on-line pressure-volume and flow-volume loops were superimposed on target loops obtained during exercise to replicate the work of breathing accurately. At ∼55 l min(-1) V̇E, V̇O2 RM was significantly greater in women. At maximal ventilation, the absolute V̇O2 RM was not different (P > 0.05) between the sexes, but represented a significantly greater fraction of whole-body V̇O2 in women (13.8 ± 1.5 vs. 9.4 ± 1.1% V̇O2). During heavy exercise at 92 and 100% V̇O2max, the unit cost of V̇E was +0.7 and +1.1 ml O2 l(-1) greater in women (P < 0.05). At V̇O2max, men and women who developed expiratory flow limitation had a significantly greater V̇O2 RM than those who did not (435 ± 44 vs. 331 ± 30 ml O2 min(-1) ). In conclusion, women have a greater V̇O2 RM for a given V̇E, and this represents a greater fraction of whole-body V̇O2. The greater V̇O2 RM in women may have implications for the integrated physiological response to exercise.
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Affiliation(s)
- Paolo B Dominelli
- School of Kinesiology, University of British Columbia, Vancouver, BC, Canada
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Elliott JE, Laurie SS, Kern JP, Beasley KM, Goodman RD, Kayser B, Subudhi AW, Roach RC, Lovering AT. AltitudeOmics: impaired pulmonary gas exchange efficiency and blunted ventilatory acclimatization in humans with patent foramen ovale after 16 days at 5,260 m. J Appl Physiol (1985) 2015; 118:1100-12. [PMID: 25678698 DOI: 10.1152/japplphysiol.00879.2014] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2014] [Accepted: 02/08/2015] [Indexed: 12/29/2022] Open
Abstract
A patent foramen ovale (PFO), present in ∼40% of the general population, is a potential source of right-to-left shunt that can impair pulmonary gas exchange efficiency [i.e., increase the alveolar-to-arterial Po2 difference (A-aDO2)]. Prior studies investigating human acclimatization to high-altitude with A-aDO2 as a key parameter have not investigated differences between subjects with (PFO+) or without a PFO (PFO-). We hypothesized that in PFO+ subjects A-aDO2 would not improve (i.e., decrease) after acclimatization to high altitude compared with PFO- subjects. Twenty-one (11 PFO+) healthy sea-level residents were studied at rest and during cycle ergometer exercise at the highest iso-workload achieved at sea level (SL), after acute transport to 5,260 m (ALT1), and again at 5,260 m after 16 days of high-altitude acclimatization (ALT16). In contrast to PFO- subjects, PFO+ subjects had 1) no improvement in A-aDO2 at rest and during exercise at ALT16 compared with ALT1, 2) no significant increase in resting alveolar ventilation, or alveolar Po2, at ALT16 compared with ALT1, and consequently had 3) an increased arterial Pco2 and decreased arterial Po2 and arterial O2 saturation at rest at ALT16. Furthermore, PFO+ subjects had an increased incidence of acute mountain sickness (AMS) at ALT1 concomitant with significantly lower peripheral O2 saturation (SpO2). These data suggest that PFO+ subjects have increased susceptibility to AMS when not taking prophylactic treatments, that right-to-left shunt through a PFO impairs pulmonary gas exchange efficiency even after acclimatization to high altitude, and that PFO+ subjects have blunted ventilatory acclimatization after 16 days at altitude compared with PFO- subjects.
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Affiliation(s)
| | - Steven S Laurie
- Department of Human Physiology, University of Oregon, Eugene, Oregon
| | - Julia P Kern
- Department of Human Physiology, University of Oregon, Eugene, Oregon
| | - Kara M Beasley
- Department of Human Physiology, University of Oregon, Eugene, Oregon
| | - Randall D Goodman
- Oregon Heart and Vascular Institute, Echocardiography, Springfield, Oregon
| | - Bengt Kayser
- University of Lausanne, Department of Physiology and Institute of Sports Sciences, Lausanne, Switzerland
| | - Andrew W Subudhi
- Altitude Research Center, University of Colorado Anschutz Medical Campus, Denver, Colorado; and Department of Biology, University of Colorado, Colorado Springs, Colorado
| | - Robert C Roach
- Altitude Research Center, University of Colorado Anschutz Medical Campus, Denver, Colorado; and
| | - Andrew T Lovering
- Department of Human Physiology, University of Oregon, Eugene, Oregon;
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