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Viscor G, Corominas J, Carceller A. Nutrition and Hydration for High-Altitude Alpinism: A Narrative Review. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2023; 20:3186. [PMID: 36833880 PMCID: PMC9965509 DOI: 10.3390/ijerph20043186] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/20/2022] [Revised: 02/03/2023] [Accepted: 02/09/2023] [Indexed: 06/18/2023]
Abstract
This report aims to summarise the scientific knowledge around hydration, nutrition, and metabolism at high altitudes and to transfer it into the practical context of extreme altitude alpinism, which, as far as we know, has never been considered before in the literature. Maintaining energy balance during alpine expeditions is difficult for several reasons and requires a deep understanding of human physiology and the biological basis for altitude acclimation. However, in these harsh conditions it is difficult to reconcile our current scientific knowledge in sports nutrition or even for mountaineering to high-altitude alpinism: extreme hypoxia, cold, and the logistical difficulties intrinsic to these kinds of expeditions are not considered in the current literature. Requirements for the different stages of an expedition vary dramatically with increasing altitude, so recommendations must differentiate whether the alpinist is at base camp, at high-altitude camps, or attempting the summit. This paper highlights nutritional recommendations regarding prioritising carbohydrates as a source of energy and trying to maintain a protein balance with a practical contextualisation in the extreme altitude environment in the different stages of an alpine expedition. More research is needed regarding specific macro and micronutrient requirements as well as the adequacy of nutritional supplementations at high altitudes.
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Affiliation(s)
- Ginés Viscor
- Secció de Fisiologia, Departament de Biologia Cel·Lular, Fisiologia i Immunologia, Facultat de Biologia, Universitat de Barcelona, 08028 Barcelona, Spain
| | - Jordi Corominas
- International Federation of Mountain Guide Associations (UIAGM/IFMGA), CH-1920 Bern, Switzerland
| | - Anna Carceller
- Secció de Fisiologia, Departament de Biologia Cel·Lular, Fisiologia i Immunologia, Facultat de Biologia, Universitat de Barcelona, 08028 Barcelona, Spain
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Fujita M, Kamibayashi K, Aoki T, Horiuchi M, Fukuoka Y. Influence of Step Frequency on the Dynamic Characteristics of Ventilation and Gas Exchange During Sinusoidal Walking in humans. Front Physiol 2022; 13:820666. [PMID: 35492612 PMCID: PMC9039249 DOI: 10.3389/fphys.2022.820666] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2021] [Accepted: 02/14/2022] [Indexed: 11/17/2022] Open
Abstract
We tested the hypothesis that restricting either step frequency (SF) or stride length (SL) causes a decrease in ventilatory response with limited breath frequency during sinusoidal walking. In this study, 13 healthy male and female volunteers (mean ± SD; age: 21.5 ± 1.8 years, height: 168 ± 7 cm, weight: 61.5 ± 8.3 kg) participated. The walking speed was sinusoidally changed between 50 and 100 m⋅min–1 with periods from 10 to 1 min. Using a customized sound system, we fixed the SF at 120 steps⋅min–1 with SL variation (0.83–0.41 m) (SFfix) or fixed the SL at 0.7 m with SF variation (143–71 steps⋅min–1) (SLfix) during the subjects’ sinusoidal walking. Both the subjects’ preferred locomotion pattern without a sound system (Free) and the unprompted spontaneous locomotor pattern for each subject (Free) served as the control condition. We measured breath-by-breath ventilation [tidal volume (VT) and breathing frequency (Bf)] and gas exchange [CO2 output (V.CO2), O2 uptake (V.O2)]. The amplitude (Amp) and the phase shift (PS) of the fundamental component of the ventilatory and gas exchange variables were calculated. The results revealed that the SFfix condition decreased the Amp of the Bf response compared with SLfix and Free conditions. Notably, the Amp of the Bf response under SFfix was reduced by less than one breath at the periods of 5 and 10 min. In contrast, the SLfix condition resulted in larger Amps of Bf and V.E responses as well as Free. We thus speculate that the steeper slope of the V.E-V.CO2 relationship observed under the SLfix might be attributable to the central feed-forward command or upward information from afferent neural activity by sinusoidal locomotive cadence. The PSs of the V.E, V.O2, and V.CO2 responses were unaffected by any locomotion patterns. Such a sinusoidal wave manipulation of locomotion variables may offer new insights into the dynamics of exercise hyperpnea.
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Affiliation(s)
- Mako Fujita
- Faculty of Health and Sports Science, Doshisha University, Kyoto, Japan
| | | | - Tomoko Aoki
- Faculty of Environmental Symbiotic Science, Prefectural University of Kumamoto, Kumamoto, Japan
| | - Masahiro Horiuchi
- Division of Human Environmental Science, Mt. Fuji Research Institute, Fujiyoshida, Japan
| | - Yoshiyuki Fukuoka
- Faculty of Health and Sports Science, Doshisha University, Kyoto, Japan
- *Correspondence: Yoshiyuki Fukuoka,
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Burtscher M, Niedermeier M, Burtscher J, Pesta D, Suchy J, Strasser B. Preparation for Endurance Competitions at Altitude: Physiological, Psychological, Dietary and Coaching Aspects. A Narrative Review. Front Physiol 2018; 9:1504. [PMID: 30425646 PMCID: PMC6218926 DOI: 10.3389/fphys.2018.01504] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2018] [Accepted: 10/05/2018] [Indexed: 01/14/2023] Open
Abstract
It was the Summer Olympic Games 1968 held in Mexico City (2,300 m) that required scientists and coaches to cope with the expected decline of performance in endurance athletes and to establish optimal preparation programs for competing at altitude. From that period until now many different recommendations for altitude acclimatization in advance of an altitude competition were proposed, ranging from several hours to several weeks. Those recommendations are mostly based on the separate consideration of the physiology of acclimatization, psychological issues, performance changes, logistical or individual aspects, but there is no review considering all these aspects in their entirety. Therefore, the present work primarily focusses on the period of altitude sojourn prior to the competition at altitude based on physiological and psychological aspects complemented by nutritional and sports practical considerations.
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Affiliation(s)
- Martin Burtscher
- Department of Sport Science, University of Innsbruck, Innsbruck, Austria.,Austrian Society for Alpine and Mountain Medicine, Innsbruck, Austria
| | - Martin Niedermeier
- Department of Sport Science, University of Innsbruck, Innsbruck, Austria
| | - Johannes Burtscher
- Laboratory of Molecular and Chemical Biology of Neurodegeneration, École Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
| | - Dominik Pesta
- Institute for Clinical Diabetology, German Diabetes Center, Leibniz Institute for Diabetes Research at Heinrich Heine University, Düsseldorf, Germany.,German Center for Diabetes Research, München-Neuherberg, Germany
| | - Jiri Suchy
- Faculty of Physical Education and Sport, Charles University, Prague, Czechia
| | - Barbara Strasser
- Department of Epidemiology and Preventive Medicine, University of Regensburg, Regensburg, Germany.,Medical School, Sigmund Freud University, Vienna, Austria
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Miyamoto T, Manabe K, Ueda S, Nakahara H. Development of an anaesthetized-rat model of exercise hyperpnoea: an integrative model of respiratory control using an equilibrium diagram. Exp Physiol 2018; 103:748-760. [PMID: 29509982 PMCID: PMC6032965 DOI: 10.1113/ep086850] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2017] [Accepted: 03/02/2018] [Indexed: 01/04/2023]
Abstract
New Findings What is the central question of this study? The lack of useful small‐animal models for studying exercise hyperpnoea makes it difficult to investigate the underlying mechanisms of exercise‐induced ventilatory abnormalities in various disease states. What is the main finding and its importance? We developed an anaesthetized‐rat model for studying exercise hyperpnoea, using a respiratory equilibrium diagram for quantitative characterization of the respiratory chemoreflex feedback system. This experimental model will provide an opportunity to clarify the major determinant mechanisms of exercise hyperpnoea, and will be useful for understanding the mechanisms responsible for abnormal ventilatory responses to exercise in disease models.
Abstract Exercise‐induced ventilatory abnormalities in various disease states seem to arise from pathological changes of respiratory regulation. Although experimental studies in small animals are essential to investigate the pathophysiological basis of various disease models, the lack of an integrated framework for quantitatively characterizing respiratory regulation during exercise prevents us from resolving these problems. The purpose of this study was to develop an anaesthetized‐rat model for studying exercise hyperpnoea for quantitative characterization of the respiratory chemoreflex feedback system. In 24 anaesthetized rats, we induced muscle contraction by stimulating bilateral distal sciatic nerves at low and high voltage to mimic exercise. We recorded breath‐by‐breath respiratory gas analysis data and cardiorespiratory responses while running two protocols to characterize the controller and plant of the respiratory chemoreflex. The controller was characterized by determining the linear relationship between end‐tidal CO2 pressure (P ETC O2) and minute ventilation (V˙E), and the plant by the hyperbolic relationship between V˙E and P ETC O2. During exercise, the controller curve shifted upward without change in controller gain, accompanying increased oxygen uptake. The hyperbolic plant curve shifted rightward and downward depending on exercise intensity as predicted by increased metabolism. Exercise intensity‐dependent changes in operating points (V˙E and P ETC O2) were estimated by integrating the controller and plant curves in a respiratory equilibrium diagram. In conclusion, we developed an anaesthetized‐rat model for studying exercise hyperpnoea, using systems analysis for quantitative characterization of the respiratory system. This novel experimental model will be useful for understanding the mechanisms responsible for abnormal ventilatory responses to exercise in disease models.
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Affiliation(s)
- Tadayoshi Miyamoto
- Graduate School of Health Sciences, Morinomiya University of Medical Sciences, Osaka City, Osaka, 559-0034, Japan.,Department of Cardiovascular Dynamics, National Cerebral and Cardiovascular Center Research Institute, Suita City, Osaka, 565-8565, Japan
| | - Kou Manabe
- Graduate School of Health Sciences, Morinomiya University of Medical Sciences, Osaka City, Osaka, 559-0034, Japan
| | - Shinya Ueda
- Graduate School of Health Sciences, Morinomiya University of Medical Sciences, Osaka City, Osaka, 559-0034, Japan
| | - Hidehiro Nakahara
- Graduate School of Health Sciences, Morinomiya University of Medical Sciences, Osaka City, Osaka, 559-0034, Japan
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Cerebral Blood Flow During Treadmill Exercise Is a Marker of Physiological Postconcussion Syndrome in Female Athletes. J Head Trauma Rehabil 2016; 31:215-24. [DOI: 10.1097/htr.0000000000000145] [Citation(s) in RCA: 90] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Townsend NE, Gore CJ, Ebert TR, Martin DT, Hahn AG, Chow CM. Ventilatory acclimatisation is beneficial for high-intensity exercise at altitude in elite cyclists. Eur J Sport Sci 2016; 16:895-902. [PMID: 26894371 DOI: 10.1080/17461391.2016.1139190] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
AIM The aim of this study was to examine the relationship between ventilatory adaptation and performance during altitude training at 2700 m. METHODS Seven elite cyclists (age: 21.2 ± 1.1 yr, body mass: 69.9 ± 5.6 kg, height 176.3 ± 4.9 cm) participated in this study. A hypoxic ventilatory response (HVR) test and a submaximal exercise test were performed at sea level prior to the training camp and again after 15 d at altitude (ALT15). Ventilation (VE), end-tidal carbon-dioxide partial pressure (PETCO2) and oxyhaemoglobin saturation via pulse oximetry (SpO2) were measured at rest and during submaximal cycling at 250 W. A hill climb (HC) performance test was conducted at sea level and after 14 d at altitude (ALT14) using a road of similar length (5.5-6 km) and gradient (4.8-5.3%). Power output was measured using SRM cranks. Average HC power at ALT14 was normalised to sea level power (HC%). Multiple regression was used to identify significant predictors of performance at altitude. RESULTS At ALT15, there was a significant increase in resting VE (10.3 ± 1.9 vs. 12.2 ± 2.4 L·min(-1)) and HVR (0.34 ± 0.24 vs. 0.71 ± 0.49 L·min(-1)·%(-1)), while PETCO2 (38.4 ± 2.3 vs. 32.1 ± 3.3 mmHg) and SpO2 (97.9 ± 0.7 vs. 94.0 ± 1.7%) were reduced (P < .05). Multiple regression revealed ΔHVR and exercise VE at altitude as significant predictors of HC% (adjusted r(2) = 0.913; P = 0.003). CONCLUSIONS Ventilatory acclimatisation occurred during a 2 wk altitude training camp in elite cyclists and a higher HVR was associated with better performance at altitude, relative to sea level. These results suggest that ventilatory acclimatisation is beneficial for cycling performance at altitude.
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Affiliation(s)
- Nathan E Townsend
- a Athlete Health and Performance Research Centre , Aspetar Orthopaedic and Sports Medicine Hospital , Doha , Qatar.,b School of Exercise and Nutrition Sciences, Deakin University , Burwood , Australia
| | - Christopher J Gore
- c Department of Physiology , Australian Institute of Sport , Canberra , Australia
| | - Tammie R Ebert
- c Department of Physiology , Australian Institute of Sport , Canberra , Australia
| | - David T Martin
- c Department of Physiology , Australian Institute of Sport , Canberra , Australia
| | - Allan G Hahn
- c Department of Physiology , Australian Institute of Sport , Canberra , Australia
| | - Chin-Moi Chow
- d School of Exercise and Sport Science, University of Sydney , Lidcombe , Australia
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Affiliation(s)
- Tadayoshi Miyamoto
- Graduate School of Health Sciences, Morinomiya University of Medical Sciences
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Miyamoto T, Nakahara H, Ueda S, Manabe K, Kawai E, Inagaki M, Kawada T, Sugimachi M. Periodic Breathing in Heart Failure Explained by Dynamic and Static Properties of Respiratory Control. CLINICAL MEDICINE INSIGHTS-CARDIOLOGY 2015; 9:133-42. [PMID: 26561001 PMCID: PMC4629632 DOI: 10.4137/cmc.s18761] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/12/2015] [Revised: 06/18/2015] [Accepted: 07/01/2015] [Indexed: 12/12/2022]
Abstract
OBJECTIVE The respiratory operating point is determined by the interplay between the controller and plant subsystem elements within the respiratory chemoreflex feedback system. This study aimed to establish the methodological basis for quantitative analysis of the open-loop dynamic properties of the human respiratory control system and to apply the results to explore detailed mechanisms of the regulation of respiration and the possible mechanism of periodic breathing in chronic heart failure. METHODS AND RESULTS In healthy volunteers, we measured arterial CO2 partial pressure (PaCO2) and minute ventilation
(V˙E) to estimate the dynamic properties of the controller (
PaCO2→V˙E relation) and plant (
V˙E→PaCO2 relation). The dynamic properties of the controller and plant approximated first- and second-order exponential models, respectively, and were described using parameters including gain, time constant, and lag time. We then used the open-loop transfer functions to simulate the closed-loop respiratory response to an exogenous disturbance, while manipulating the parameter values to deviate from normal values but within physiological ranges. By increasing both the product of gains of the two subsystem elements (total loop gain) and the lag time, the condition of system oscillation (onset of periodic breathing) was satisfied. CONCLUSION When abnormality occurs in a part of the respiratory chemoreflex system, instability of the control system is amplified and may result in the manifestation of respiratory abnormalities such as periodic breathing.
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Affiliation(s)
- Tadayoshi Miyamoto
- Graduate School of Health Sciences, Morinomiya University of Medical Sciences, Osaka City, Osaka, Japan
| | - Hidehiro Nakahara
- Graduate School of Health Sciences, Morinomiya University of Medical Sciences, Osaka City, Osaka, Japan
| | - Shinya Ueda
- Graduate School of Health Sciences, Morinomiya University of Medical Sciences, Osaka City, Osaka, Japan
| | - Kou Manabe
- Graduate School of Health Sciences, Morinomiya University of Medical Sciences, Osaka City, Osaka, Japan
| | - Eriko Kawai
- Graduate School of Health Sciences, Morinomiya University of Medical Sciences, Osaka City, Osaka, Japan
| | - Masashi Inagaki
- Department of Cardiovascular Dynamics, National Cerebral and Cardiovascular Center, Suita City, Osaka, Japan
| | - Toru Kawada
- Department of Cardiovascular Dynamics, National Cerebral and Cardiovascular Center, Suita City, Osaka, Japan
| | - Masaru Sugimachi
- Department of Cardiovascular Dynamics, National Cerebral and Cardiovascular Center, Suita City, Osaka, Japan
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Nakahara H, Ueda SY, Miyamoto T. Low-frequency severe-intensity interval training improves cardiorespiratory functions. Med Sci Sports Exerc 2015; 47:789-98. [PMID: 25137370 DOI: 10.1249/mss.0000000000000477] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
PURPOSE The present study investigated the effects of severe-intensity interval training at a frequency of once a week on cardiorespiratory function at rest and during exercise. METHODS Fourteen young healthy males were randomly assigned to either an interval training group or control group. Cardiorespiratory function was investigated by incremental maximal exercise test and constant work rate submaximal exercise test before and after the intervention period in all subjects. Submaximal exercise test was conducted at two work rates (80% ventilatory threshold (VT) level and 100% VT level plus 50% of the difference between VT and peak oxygen consumption (V˙O2)) for 8 min; the same work rates and duration were used before and after training. Left ventricular adaptations were assessed by echocardiography under supine resting conditions before and after training. In the interval training group, seven subjects performed cycle ergometer training once per week for 3 months. The training consisted of three bouts of exercises to volitional fatigue at 80% maximum work rate. RESULTS Increased V˙O2max (+13%, P = 0.015), VT (+21%, P = 0.001), and left ventricular posterior wall thickness (+18%, P = 0.002) and reduced minute ventilation (-12%, P = 0.032) and blood lactate concentration (-16%, P = 0.025) during high-intensity exercise were observed after the training program compared with baseline. Although not significant, V˙O2 and cycling economy (V˙O2 per work rate) during high-intensity exercise decreased slightly after training. CONCLUSION The present results indicate that severe-intensity interval training, even when performed at a low frequency, markedly improves cardiorespiratory function as well as induces cardiac morphological adaptations involving left ventricular hypertrophy and cardiorespiratory metabolic response during submaximal exercise. The present findings may provide new insights for low-frequency, severe-intensity interval training in the field of sports science.
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Affiliation(s)
- Hidehiro Nakahara
- Graduate School of Health Sciences, Morinomiya University of Medical Sciences, Osaka City, JAPAN
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Caterini JE, Duffin J, Wells GD. Limb movement frequency is a significant modulator of the ventilatory response during submaximal cycling exercise in humans. Respir Physiol Neurobiol 2015; 220:10-6. [PMID: 26369445 DOI: 10.1016/j.resp.2015.09.004] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2015] [Revised: 07/16/2015] [Accepted: 09/10/2015] [Indexed: 11/27/2022]
Abstract
Human experimentation investigating the contribution of limb movement frequency in determining the fast exercise drive to breathe has produced controversial findings. To evaluate the role of limb movement frequency in determining the fast exercise drive to breathe, endurance runners and recreationally-active controls performed two sinusoidal exercise protocols on a cycle ergometer. One protocol was performed at constant workload with sinusoidal pedaling cadence, and a second with sinusoidal workload at constant cadence. Metabolic rate (VO2) increases and means were matched between these two experiments. The ventilatory response was significantly faster when limb movement speed was varied, compared to when pedal loading was varied (18.49 ± 15.6s vs. 50.5 ± 14.5s, p<0.05). Ventilation response amplitudes were significantly higher during pedal cadence variation versus pedal loading variation (3.99 ± 0.25 vs. 2.58 ± 0.17 L/min, p<0.05). Similar findings were obtained for endurance athletes, with significantly attenuated ventilation responses to exercise versus control subjects. We conclude that fast changes in limb movement frequency are a potent stimulus for ventilation at submaximal workloads, and that this response is susceptible to attenuation through training.
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Affiliation(s)
- Jessica E Caterini
- Graduate Department of Exercise Sciences, University of Toronto, 100 Devonshire Place, Toronto, Ontario M5S 2C9, Canada; Physiology and Experimental Medicine, The Hospital for Sick Children, 555 University Avenue, Toronto, Ontario M5G 1X8, Canada
| | - James Duffin
- Department of Physiology, University of Toronto, 1 King's College Circle, Toronto, Ontario M5S 1A8, Canada; Department of Anaesthesia, University of Toronto Health Network, 200 Elizabeth St., Toronto, Ontario M5G 2C4 Canada
| | - Gregory D Wells
- Physiology and Experimental Medicine, The Hospital for Sick Children, 555 University Avenue, Toronto, Ontario M5G 1X8, Canada; Faculty of Kinesiology and Physical Education, University of Toronto, 100 Devonshire Place, Toronto, Ontario M5S2C9, Canada.
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Miyamoto T, Bailey DM, Nakahara H, Ueda S, Inagaki M, Ogoh S. Manipulation of central blood volume and implications for respiratory control function. Am J Physiol Heart Circ Physiol 2014; 306:H1669-78. [DOI: 10.1152/ajpheart.00987.2013] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The respiratory operating point (ventilatory or arterial Pco2 response) is determined by the intersection point between the controller and plant subsystem elements within the respiratory control system. However, to what extent changes in central blood volume (CBV) influence these two elements and the corresponding implications for the respiratory operating point remain unclear. To examine this, 17 apparently healthy male participants were exposed to water immersion (WI) or lower body negative pressure (LBNP) challenges to manipulate CBV and determine the corresponding changes. The respiratory controller was characterized by determining the linear relationship between end-tidal Pco2 (PetCO2) and minute ventilation (V̇e) [V̇e = S × (PetCO2 − B)], whereas the plant was determined by the hyperbolic relationship between V̇e and PetCO2 (PetCO2 = A/V̇e + C). Changes in V̇e at the operating point were not observed under either WI or LBNP conditions despite altered PetCO2 ( P < 0.01), indicating a moving respiratory operating point. An increase (WI) and a decrease (LBNP) in CBV were shown to reset the controller element (PetCO2 intercept B) rightward and leftward, respectively ( P < 0.05), without any change in S, whereas the plant curve remained unaltered at the operating point. Collectively, these findings indicate that modification of the controller element rather than the plant element is the major factor that contributes toward an alteration of the respiratory operating point during CBV shifts.
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Affiliation(s)
- Tadayoshi Miyamoto
- Graduate School of Health Sciences, Morinomiya University of Medical Sciences, Osaka City, Osaka, Japan
- Department of Cardiovascular Dynamics, National Cerebral and Cardiovascular Center Research Institute, Suita City, Osaka, Japan
| | - Damian Miles Bailey
- Neurovascular Research Laboratory, Faculty of Life Sciences and Education, University of South Wales, Wales, United Kingdom; and
| | - Hidehiro Nakahara
- Graduate School of Health Sciences, Morinomiya University of Medical Sciences, Osaka City, Osaka, Japan
| | - Shinya Ueda
- Graduate School of Health Sciences, Morinomiya University of Medical Sciences, Osaka City, Osaka, Japan
| | - Masashi Inagaki
- Department of Cardiovascular Dynamics, National Cerebral and Cardiovascular Center Research Institute, Suita City, Osaka, Japan
| | - Shigehiko Ogoh
- Department of Biomedical Engineering, Toyo University, Kawagoe City, Saitama, Japan
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