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Koirala B, Concas A, Sun Y, Gladden LB, Lai N. Relationship between muscle venous blood oxygenation and near-infrared spectroscopy: quantitative analysis of the Hb and Mb contributions. J Appl Physiol (1985) 2023; 134:1063-1074. [PMID: 36927143 PMCID: PMC10125031 DOI: 10.1152/japplphysiol.00406.2022] [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: 07/12/2022] [Revised: 02/22/2023] [Accepted: 03/13/2023] [Indexed: 03/18/2023] Open
Abstract
A linear relationship between skeletal muscle venous ([Formula: see text]) and oxygenated (ΔHbMbO2,N) or deoxygenated (ΔHHbMbN) near-infrared spectroscopy (NIRS) signals suggest a main hemoglobin (Hb) contribution to the NIRS signal. However, experimental, and computational evidence supports a significant contribution of myoglobin (Mb) to the NIRS. Venous and NIRS measurements from a canine model of muscle oxidative metabolism (Sun Y, Ferguson BS, Rogatzki MJ, McDonald JR, Gladden LB. Med Sci Sports Exerc 48(10):2013-2020, 2016) were integrated into a computational model of muscle O2 transport and utilization to evaluate whether the relationship between venous and NIRS oxygenation can be affected by a significant Mb contribution to the NIRS signals. The mathematical model predicted well the measure of the changes of [Formula: see text] and NIRS signals for different O2 delivery conditions (blood flow, arterial O2 content) in muscle at rest (T1, T2) and during contraction (T3). Furthermore, computational analysis indicates that for adequate O2 delivery, Mb contribution to NIRS signals was significant (20%-30%) even in the presence of a linear [Formula: see text]-NIRS relationship; for a reduced O2 delivery the nonlinearity of the [Formula: see text]-NIRS relationship was related to the Mb contribution (50%). In this case (T3), the deviation from linearity is observed when O2 delivery is reduced from 1.3 to 0.7 L kg-1·min-1 ([Formula: see text] < 10 mLO2 100 mL-1) and Mb saturation decreased from 85% to 40% corresponding to an increase of the Mb contribution to ΔHHbMbN from 15% to 50% and the contribution to ΔHbMbO2,N from 0% to 30%. In contrast to a common assumption, our model indicates that both NIRS signals (ΔHHbMbN and ΔHbMbO2,N are significantly affected by Hb and Mb oxygenation changes.NEW & NOTEWORTHY Within the near-infrared spectroscopy (NIRS) signal, the contribution from hemoglobin is indistinguishable from that of myoglobin. A computation analysis indicates that a linear relationship between muscle venous oxygen content and NIRS signals does not necessarily indicate a negligible myoglobin contribution to the NIRS signal. A reduced oxygen delivery increases the myoglobin contribution to the NIRS signal. The integrative approach proposed is a powerful way to assist in interpreting the elements from which the NIRS signals are derived.
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Affiliation(s)
- Bhabuk Koirala
- Department of Electrical and Computer Engineering, Old Dominion University, Norfolk, Virginia United States
- Biomedical Engineering Institute, Old Dominion University, Norfolk, Virginia, United States
| | - Alessandro Concas
- Department of Mechanical, Chemical and Materials Engineering, University of Cagliari, Italy
| | - Yi Sun
- Key Laboratory of Adolescent Health Assessment and Exercise Intervention of Ministry of Education, East China Normal University, Shanghai, China
- School of Physical Education & Health Care, East China Normal University, Shanghai, People's Republic of China
| | - L Bruce Gladden
- School of Kinesiology, Auburn University, Auburn, Alabama United States
| | - Nicola Lai
- Department of Mechanical, Chemical and Materials Engineering, University of Cagliari, Italy
- Department of Electrical and Computer Engineering, Old Dominion University, Norfolk, Virginia United States
- Biomedical Engineering Institute, Old Dominion University, Norfolk, Virginia, United States
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Rowland SN, Da Boit M, Tan R, Robinson GP, O’Donnell E, James LJ, Bailey SJ. Dietary Nitrate Supplementation Enhances Performance and Speeds Muscle Deoxyhaemoglobin Kinetics during an End-Sprint after Prolonged Moderate-Intensity Exercise. Antioxidants (Basel) 2022; 12:antiox12010025. [PMID: 36670889 PMCID: PMC9854517 DOI: 10.3390/antiox12010025] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2022] [Revised: 12/18/2022] [Accepted: 12/21/2022] [Indexed: 12/24/2022] Open
Abstract
Short-term dietary nitrate (NO3−) supplementation has the potential to enhance performance during submaximal endurance, and short-duration, maximal-intensity exercise. However, it has yet to be determined whether NO3− supplementation before and during submaximal endurance exercise can improve performance during a short-duration, maximal-intensity end-sprint. In a randomised, double-blind, crossover study, 9 recreationally active men ingested NO3−-rich (BR: 8 mmol NO3−/day) and NO3−-depleted (PL: 0.75 mmol NO3−/day) beetroot powder for 7 days. On day 7, participants completed 2 h of moderate-intensity cycling, which immediately transitioned into a 60 s maximal-intensity end-sprint, with supplements ingested 2 h before and 1 h into the moderate-intensity exercise bout. Plasma [NO3−] and [NO2−] were higher in BR compared to PL pre- and post-exercise (p < 0.05). Post-exercise plasma [NO3−] was higher than pre-exercise (562 ± 89 µM vs. 300 ± 73 µM; p < 0.05) and plasma [NO2−] was not significantly different pre- (280 ± 58 nM) and post-exercise (228 ± 63 nM) in the BR condition (p > 0.05). Mean power output during the final 30 s of the end-sprint was greater after BR (390 ± 38 W) compared to PL (365 ± 41 W; p < 0.05). There were no differences between BR and PL in any muscle oxygenation variables during moderate-intensity cycling (p > 0.05), but muscle [deoxyhaemoglobin] kinetics was faster during the end-sprint in BR (6.5 ± 1.4 s) compared to PL (7.3 ± 1.4 s; p < 0.05). These findings suggest that NO3− supplementation has the potential to improve end-sprint performance in endurance events when ingested prior to and during exercise.
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Affiliation(s)
- Samantha N. Rowland
- School of Sport, Exercise and Health Sciences, Loughborough University, Loughborough LE11 3TU, UK
| | - Mariasole Da Boit
- Health and Life Sciences, School of Allied Health Sciences, De Montfort University, Leicester LE1 9BH, UK
| | - Rachel Tan
- Department of Sports Medicine, Pepperdine University, Malibu, CA 90263, USA
| | - George P. Robinson
- School of Sport, Exercise and Health Sciences, Loughborough University, Loughborough LE11 3TU, UK
| | - Emma O’Donnell
- School of Sport, Exercise and Health Sciences, Loughborough University, Loughborough LE11 3TU, UK
| | - Lewis J. James
- School of Sport, Exercise and Health Sciences, Loughborough University, Loughborough LE11 3TU, UK
| | - Stephen J. Bailey
- School of Sport, Exercise and Health Sciences, Loughborough University, Loughborough LE11 3TU, UK
- Correspondence:
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Peden DL, Mitchell EA, Bailey SJ, Ferguson RA. Ischaemic preconditioning blunts exercise-induced mitochondrial dysfunction, speeds oxygen uptake kinetics but does not alter severe-intensity exercise capacity. Exp Physiol 2022; 107:1241-1254. [PMID: 36030522 PMCID: PMC9826326 DOI: 10.1113/ep090264] [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: 12/15/2021] [Accepted: 08/12/2022] [Indexed: 01/11/2023]
Abstract
NEW FINDINGS What is the central question of this study? Ischaemic preconditioning is a novel pre-exercise priming strategy. We asked whether ischaemic preconditioning would alter mitochondrial respiratory function and pulmonary oxygen uptake kinetics and improve severe-intensity exercise performance. What is the main finding and its importance? Ischaemic preconditioning expedited overall pulmonary oxygen uptake kinetics and appeared to prevent an increase in leak respiration, proportional to maximal electron transfer system and ADP-stimulated respiration, that was evoked by severe-intensity exercise in sham-control conditions. However, severe-intensity exercise performance was not improved. The results do not support ischaemic preconditioning as a pre-exercise strategy to improve exercise performance in recreationally active participants. ABSTRACT We examined the effect of ischaemic preconditioning (IPC) on severe-intensity exercise performance, pulmonary oxygen uptake ( V ̇ O 2 ${\dot V_{{{\rm{O}}_{\rm{2}}}}}$ ) kinetics, skeletal muscle oxygenation (muscle tissue O2 saturation index) and mitochondrial respiration. Eight men underwent contralateral IPC (4 × 5 min at 220 mmHg) or sham-control (SHAM; 20 mmHg) before performing a cycling time-to-exhaustion test (92% maximum aerobic power). Muscle (vastus lateralis) biopsies were obtained before IPC or SHAM and ∼1.5 min postexercise. The time to exhaustion did not differ between SHAM and IPC (249 ± 37 vs. 240 ± 32 s; P = 0.62). Pre- and postexercise ADP-stimulated (P) and maximal (E) mitochondrial respiration through protein complexes (C) I, II and IV did not differ (P > 0.05). Complex I leak respiration was greater postexercise compared with baseline in SHAM, but not in IPC, when normalized to wet mass (P = 0.01 vs. P = 0.19), mitochondrial content (citrate synthase activity, P = 0.003 vs. P = 0.16; CI+IIP, P = 0.03 vs. P = 0.23) and expressed relative to P (P = 0.006 vs. P = 0.30) and E (P = 0.004 vs. P = 0.26). The V ̇ O 2 ${\dot V_{{{\rm{O}}_{\rm{2}}}}}$ mean response time was faster (51.3 ± 15.5 vs. 63.7 ± 14.5 s; P = 0.003), with a smaller slow component (270 ± 105 vs. 377 ± 188 ml min-1 ; P = 0.03), in IPC compared with SHAM. The muscle tissue O2 saturation index did not differ between trials (P > 0.05). Ischaemic preconditioning expedited V ̇ O 2 ${\dot V_{{{\rm{O}}_{\rm{2}}}}}$ kinetics and appeared to prevent an increase in leak respiration through CI, when expressed proportional to E and P evoked by severe-intensity exercise, but did not improve exercise performance.
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Affiliation(s)
- Donald L. Peden
- School of SportExercise and Health SciencesLoughborough UniversityLoughboroughUK
| | - Emma A. Mitchell
- School of SportExercise and Health SciencesLoughborough UniversityLoughboroughUK
| | - Stephen J. Bailey
- School of SportExercise and Health SciencesLoughborough UniversityLoughboroughUK
| | - Richard A. Ferguson
- School of SportExercise and Health SciencesLoughborough UniversityLoughboroughUK
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Park SY, Wooden TK, Pekas EJ, Anderson CP, Yadav SK, Slivka DR, Layec G. Effects of passive and active leg movements to interrupt sitting in mild hypercapnia on cardiovascular function in healthy adults. J Appl Physiol (1985) 2022; 132:874-887. [PMID: 35175102 PMCID: PMC8934680 DOI: 10.1152/japplphysiol.00799.2021] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Prolonged sitting in a mild hypercapnic environment impairs peripheral vascular function. The effects of sitting interruptions using passive or active skeletal muscle contractions are still unclear. Therefore, we sought to examine the vascular effects of brief periods (2 min every half hour) of passive and active lower limb movement to interrupt prolonged sitting with mild hypercapnia in adults. Fourteen healthy adults (24 ± 2 yr) participated in three experimental visits sitting for 2.5 h in a mild hypercapnic environment (CO2 = 1,500 ppm): control (CON, no limb movement), passive lower limb movement (PASS), and active lower limb movement (ACT) during sitting. At all visits, brachial and popliteal artery flow-mediated dilation (FMD), microvascular function, plasmatic levels of nitrate/nitrite and endothelin-1, and heart rate variability were assessed before and after sitting. Brachial and popliteal artery FMDs were reduced in CON and PASS (P < 0.05) but were preserved (P > 0.05) in ACT. Microvascular function was blunted in CON (P < 0.05) but was preserved in PASS and ACT (P > 0.05). In addition, total plasma nitrate/nitrite was preserved in ACT (P > 0.05) but was reduced in CON and PASS (P < 0.05), and endothelin-1 levels were decreased in ACT (P < 0.05). Both passive and active movement induced a greater ratio between the low-frequency and high-frequency bands for heart rate variability (P < 0.05). For the first time, to our knowledge, we found that brief periods of passive leg movement can preserve microvascular function, but that an intervention that elicits larger increases in shear rate, such as low-intensity exercise, is required to fully protect both macrovascular and microvascular function and circulating vasoactive substance balance.NEW & NOTEWORTHY Passive leg movement could not preserve macrovascular endothelial function, whereas active leg movement could protect endothelial function. Attenuated microvascular function can be salvaged by passive movement and active movement. Preservation of macrovascular hemodynamics and plasma total nitrate/nitrite and endothelin-1 during prolonged sitting requires active movement. These findings dissociate the impacts induced by mechanical stress (passive movement) from the change in metabolism (active movement) on the vasculature during prolonged sitting in a mild hypercapnic environment.
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Affiliation(s)
- Song-Young Park
- 1School of Health and Kinesiology, University of Nebraska Omaha, Omaha, Nebraska
| | - TeSean K. Wooden
- 1School of Health and Kinesiology, University of Nebraska Omaha, Omaha, Nebraska
| | - Elizabeth J. Pekas
- 1School of Health and Kinesiology, University of Nebraska Omaha, Omaha, Nebraska
| | - Cody P. Anderson
- 1School of Health and Kinesiology, University of Nebraska Omaha, Omaha, Nebraska
| | - Santosh K. Yadav
- 2Department of Biochemistry and Molecular Biology, University of Nebraska Medical Center, Omaha, Nebraska
| | - Dustin R. Slivka
- 1School of Health and Kinesiology, University of Nebraska Omaha, Omaha, Nebraska
| | - Gwenael Layec
- 3Department of Kinesiology, University of Massachusetts Amherst, Amherst, Massachusetts,4Institute for Applied Life Sciences, Amherst, Massachusetts
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Shimotsu R, Hotta K, Ikegami R, Asamura T, Tabuchi A, Masamoto K, Yagishita K, Poole DC, Kano Y. Vascular permeability of skeletal muscle microvessels in rat arterial ligation model: in vivo analysis using two-photon laser scanning microscopy. Am J Physiol Regul Integr Comp Physiol 2021; 320:R972-R983. [PMID: 33949210 DOI: 10.1152/ajpregu.00135.2020] [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: 05/22/2020] [Accepted: 04/23/2021] [Indexed: 11/22/2022]
Abstract
Peripheral artery disease (PAD) in the lower limb compromises oxygen supply due to arterial occlusion. Ischemic skeletal muscle is accompanied by capillary structural deformation. Therefore, using novel microscopy techniques, we tested the hypothesis that endothelial cell swelling temporally and quantitatively corresponds to enhanced microvascular permeability. Hindlimb ischemia was created in male Wistar rat's by iliac artery ligation (AL). The tibialis anterior (TA) muscle microcirculation was imaged using intravenously infused rhodamine B isothiocyanate dextran fluorescent dye via two-photon laser scanning microscopy (TPLSM) and dye extravasation at 3 and 7 days post-AL quantified to assess microvascular permeability. The TA microvascular endothelial ultrastructure was analyzed by transmission electron microscopy (TEM). Compared with control (0.40 ± 0.15 μm3 × 106), using TPLSM, the volumetrically determined interstitial leakage of fluorescent dye measured at 3 (3.0 ± 0.40 μm3 × 106) and 7 (2.5 ± 0.8 μm3 × 106) days was increased (both P < 0.05). Capillary wall thickness was also elevated at 3 (0.21 ± 0.06 μm) and 7 (0.21 ± 0.08 μm) days versus control (0.11 ± 0.03 μm, both P < 0.05). Capillary endothelial cell swelling was temporally and quantitatively associated with elevated vascular permeability in the AL model of PAD but these changes occurred in the absence of elevations in protein levels of vascular endothelial growth factor (VEGF) its receptor (VEGFR2 which decreased by AL-7 day) or matrix metalloproteinase. The temporal coherence of endothelial cell swelling and increased vascular permeability supports a common upstream mediator. TPLSM, in combination with TEM, provides a sensitive and spatially discrete technique to assess the mechanistic bases for, and efficacy of, therapeutic countermeasures to the pernicious sequelae of compromised peripheral arterial function.
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Affiliation(s)
- Rie Shimotsu
- Department of Engineering Science, University of Electro-Communications, Chofu, Japan
| | - Kzuki Hotta
- Department of Engineering Science, University of Electro-Communications, Chofu, Japan
- Department of Physical Therapy, Niigata University of Health and Welfare, Niigata, Japan
| | - Ryo Ikegami
- Department of Engineering Science, University of Electro-Communications, Chofu, Japan
- Department of Physical Therapy, Niigata University of Health and Welfare, Niigata, Japan
- Department of Health Science, Health Science University, Yamanashi, Japan
| | - Tomoyo Asamura
- Department of Engineering Science, University of Electro-Communications, Chofu, Japan
| | - Ayaka Tabuchi
- Department of Engineering Science, University of Electro-Communications, Chofu, Japan
| | - Kazuto Masamoto
- Faculty of Informatics and Engineering, University of Electro-Communications, Chofu, Japan
- Center for Neuroscience and Biomedical Engineering (CNBE), University of Electro-Communications, Chofu, Japan
| | - Kazuyoshi Yagishita
- Clinical Center for Sports Medicine and Sports Dentistry, Hyperbaric Medical Center, Tokyo Medical and Dental University, Tokyo, Japan
| | - David C Poole
- Department of Anatomy and Physiology, Kansas State University, Manhattan, Kansas
- Department of Kinesiology, Kansas State University, Manhattan, Kansas
| | - Yutaka Kano
- Department of Engineering Science, University of Electro-Communications, Chofu, Japan
- Center for Neuroscience and Biomedical Engineering (CNBE), University of Electro-Communications, Chofu, Japan
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Rokkedal-Lausch T, Franch J, Poulsen MK, Thomsen LP, Weitzberg E, Kamavuako EN, Karbing DS, Larsen RG. Multiple-day high-dose beetroot juice supplementation does not improve pulmonary or muscle deoxygenation kinetics of well-trained cyclists in normoxia and hypoxia. Nitric Oxide 2021; 111-112:37-44. [PMID: 33831566 DOI: 10.1016/j.niox.2021.03.006] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2020] [Revised: 03/24/2021] [Accepted: 03/31/2021] [Indexed: 10/21/2022]
Abstract
Dietary nitrate (NO3-) supplementation via beetroot juice (BR) has been reported to lower oxygen cost (i.e., increased exercise efficiency) and speed up oxygen uptake (VO2) kinetics in untrained and moderately trained individuals, particularly during conditions of low oxygen availability (i.e., hypoxia). However, the effects of multiple-day, high dose (12.4 mmol NO3- per day) BR supplementation on exercise efficiency and VO2 kinetics during normoxia and hypoxia in well-trained individuals are not resolved. In a double-blinded, randomized crossover study, 12 well-trained cyclists (66.4 ± 5.3 ml min-1∙kg-1) completed three transitions from rest to moderate-intensity (~70% of gas exchange threshold) cycling in hypoxia and normoxia with supplementation of BR or nitrate-depleted BR as placebo. Continuous measures of VO2 and muscle (vastus lateralis) deoxygenation (ΔHHb, using near-infrared spectroscopy) were acquired during all transitions. Kinetics of VO2 and deoxygenation (ΔHHb) were modeled using mono-exponential functions. Our results showed that BR supplementation did not alter the primary time constant for VO2 or ΔHHb during the transition from rest to moderate-intensity cycling. While BR supplementation lowered the amplitude of the VO2 response (2.1%, p = 0.038), BR did not alter steady state VO2 derived from the fit (p = 0.258), raw VO2 data (p = 0.231), moderate intensity exercise efficiency (p = 0.333) nor steady state ΔHHb (p = 0.224). Altogether, these results demonstrate that multiple-day, high-dose BR supplementation does not alter exercise efficiency or oxygen uptake kinetics during normoxia and hypoxia in well-trained athletes.
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Affiliation(s)
- Torben Rokkedal-Lausch
- Sport Sciences - Performance and Technology, Department of Health Science and Technology, Aalborg University, DK-9220, Aalborg, Denmark.
| | - Jesper Franch
- Sport Sciences - Performance and Technology, Department of Health Science and Technology, Aalborg University, DK-9220, Aalborg, Denmark
| | - Mathias K Poulsen
- Respiratory and Critical Care Group, Department of Health Science and Technology, Aalborg University, DK-9220, Aalborg, Denmark
| | - Lars P Thomsen
- Respiratory and Critical Care Group, Department of Health Science and Technology, Aalborg University, DK-9220, Aalborg, Denmark
| | - Eddie Weitzberg
- Department of Physiology and Pharmacology, Karolinska Institutet, 171 77, Stockholm, Sweden
| | - Ernest N Kamavuako
- Center for Robotics Research, Department of Engineering, King's College London, London, United Kingdom
| | - Dan S Karbing
- Respiratory and Critical Care Group, Department of Health Science and Technology, Aalborg University, DK-9220, Aalborg, Denmark
| | - Ryan G Larsen
- Sport Sciences - Performance and Technology, Department of Health Science and Technology, Aalborg University, DK-9220, Aalborg, Denmark
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Cisterna B, Sobolev AP, Costanzo M, Malatesta M, Zancanaro C. Combined Microscopic and Metabolomic Approach to Characterize the Skeletal Muscle Fiber of the Ts65Dn Mouse, A Model of Down Syndrome. MICROSCOPY AND MICROANALYSIS : THE OFFICIAL JOURNAL OF MICROSCOPY SOCIETY OF AMERICA, MICROBEAM ANALYSIS SOCIETY, MICROSCOPICAL SOCIETY OF CANADA 2020; 26:1014-1023. [PMID: 32867866 DOI: 10.1017/s143192762002437x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Down syndrome (DS) is a genetically based disease caused by triplication of chromosome 21. DS is characterized by severe muscle weakness associated with motor deficits; however, understanding the DS-associated skeletal muscle condition is limited. In this study, we used a combined methodological approach involving light and electron microscopy, as well as nuclear magnetic resonance spectroscopy metabolomics, to investigate morphology and composition of the quadriceps muscles in the Ts65Dn mouse, a model of DS, to identify structural and/or functional trisomy-associated alterations. Morphometric analysis demonstrated a larger size of myofibers in trisomic versus euploid mice; however, myofibrils were thinner and contained higher amounts of mitochondria and lipid droplets. In trisomic mice, magnetic resonance spectroscopy showed a tendency to an overall increase in muscle metabolites involved in protein synthesis. These data strongly suggest that in DS, a sarcoplasmic hypertrophy associated with myofibril loss characterizes quadriceps myofibers. In addition, large-sized mitochondria suggestive of impaired fission/fusion events, as well as metabolites modifications suggestive of decreased mitochondrial function, were found in the trisomic muscle. Albeit preliminary, the results provided by this novel approach consistently indicate structural and compositional alterations of the DS skeletal muscle, which are typical of early aging.
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Affiliation(s)
- Barbara Cisterna
- Anatomy and Histology Section, Department of Neurosciences, Biomedicine and Movement Sciences, University of Verona, Strada Le Grazie 8, VeronaI-37134, Italy
| | - Anatoly P Sobolev
- Magnetic Resonance Laboratory "Annalaura Segre", Institute for Biological Systems, National Research Council, via Salaria km 29.300, Monterotondo, RomeI-00015, Italy
| | - Manuela Costanzo
- Anatomy and Histology Section, Department of Neurosciences, Biomedicine and Movement Sciences, University of Verona, Strada Le Grazie 8, VeronaI-37134, Italy
| | - Manuela Malatesta
- Anatomy and Histology Section, Department of Neurosciences, Biomedicine and Movement Sciences, University of Verona, Strada Le Grazie 8, VeronaI-37134, Italy
| | - Carlo Zancanaro
- Anatomy and Histology Section, Department of Neurosciences, Biomedicine and Movement Sciences, University of Verona, Strada Le Grazie 8, VeronaI-37134, Italy
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8
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Nimmerichter A, Breese BC, Prinz B, Zoeger M, Rumpl C, Williams CA. Test-retest reliability of pulmonary oxygen uptake and muscle deoxygenation during moderate- and heavy-intensity cycling in youth elite-cyclists. J Sports Sci 2020; 38:2462-2470. [PMID: 32654597 DOI: 10.1080/02640414.2020.1792115] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
To establish the test-retest reliability of pulmonary oxygen uptake (V̇O2), muscle deoxygenation (deoxy[haem]) and tissue oxygen saturation (StO2) kinetics in youth elite-cyclists. From baseline pedalling, 15 youth cyclists completed 6-min step transitions to a moderate- and heavy-intensity work rate separated by 8 min of baseline cycling. The protocol was repeated after 1 h of passive rest. V̇O2 was measured breath-by-breath alongside deoxy[haem] and StO2 of the vastus lateralis by near-infrared spectroscopy. Reliability was assessed using 95% limits of agreement (LoA), the typical error (TE) and the intraclass correlation coefficient (ICC). During moderate- and heavy-intensity step cycling, TEs for the amplitude, time delay and time constant ranged between 3.5-21.9% and 3.9-12.1% for V̇O2 and between 6.6-13.7% and 3.5-10.4% for deoxy[haem], respectively. The 95% confidence interval for estimating the kinetic parameters significantly improved for ensemble-averaged transitions of V̇O2 (p < 0.01) but not for deoxy[haem]. For StO2, the TEs for the baseline, end-exercise and the rate of deoxygenation were 1.0-42.5% and 1.1-5.5% during moderate- and heavy-intensity exercise, respectively. The ICC ranged from 0.81 to 0.99 for all measures. Test-retest reliability data provide limits within which changes in V̇O2, deoxy[haem] and StO2 kinetics may be interpreted with confidence in youth athletes.
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Affiliation(s)
- Alfred Nimmerichter
- Training and Sports Sciences, University of Applied Sciences Wiener Neustadt , Wiener Neustadt, Austria
| | - Brynmor C Breese
- School of Biomedical Sciences, Faculty of Medicine and Dentistry, University of Plymouth , Plymouth, UK
| | - Bernhard Prinz
- Training and Sports Sciences, University of Applied Sciences Wiener Neustadt , Wiener Neustadt, Austria
| | - Manfred Zoeger
- Training and Sports Sciences, University of Applied Sciences Wiener Neustadt , Wiener Neustadt, Austria
| | - Clemens Rumpl
- Training and Sports Sciences, University of Applied Sciences Wiener Neustadt , Wiener Neustadt, Austria
| | - Craig A Williams
- Children's Health and Exercise Research Centre, Sport and Health Sciences, College of Life and Environmental Sciences, University of Exeter , Exeter, UK
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9
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Headid RJ, Pekas EJ, Wooden TK, Son WM, Layec G, Shin J, Park SY. Impacts of prolonged sitting with mild hypercapnia on vascular and autonomic function in healthy recreationally active adults. Am J Physiol Heart Circ Physiol 2020; 319:H468-H480. [PMID: 32648821 DOI: 10.1152/ajpheart.00354.2020] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Prolonged sitting, which is known to impair peripheral vascular function, often occurs in spaces (e.g., offices) with mild hypercapnic atmospheres. However, the effects of prolonged sitting in hypercapnic conditions on vascular function are unknown. Therefore, the purpose of this study was to investigate the effects of prolonged sitting in mild hypercapnic conditions on vascular and autonomic function in humans. Twelve healthy young adults participated in two experimental visits that consisted of sitting for 2.5 h in a control condition [normal atmospheric conditions sitting (PSIT)] or a mild hypercapnic condition (HCAP; CO2 = 1,500 ppm). During each visit, heart rate variability (HRV), blood pressure (BP), pulse wave velocity (PWV), augmentation index (AIx), brachial and popliteal artery flow-mediated dilation (FMD), and near-infrared spectroscopy (NIRS) were assessed before and after prolonged sitting. Sitting significantly decreased AIx in both groups (P < 0.05). Brachial and popliteal FMD were reduced with sitting (P < 0.05), and the reduction in popliteal FMD was amplified by HCAP (P < 0.05). Baseline microvascular oxygenation was decreased following sitting in both groups (P < 0.05). However, microvascular reoxygenation upon cuff release was slower only in HCAP (P < 0.05). HRV, HR, BP, and PWV did not significantly change with sitting in either group (P > 0.05). We conclude that prolonged sitting attenuated both brachial and popliteal endothelial function and was associated with perturbed microcirculation. Additionally, mild hypercapnic conditions further impaired peripheral endothelial and microvascular function. Together, these findings suggest that prolonged sitting is accompanied by a host of deleterious effects on the vasculature, which are exacerbated by mild hypercapnia.NEW & NOTEWORTHY The results of this study reveal that prolonged sitting attenuates endothelial function and microvascular function. Additionally, prolonged sitting with mild hypercapnia, which is similar to everyday environments, further exacerbates peripheral endothelial function and microvascular function.
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Affiliation(s)
- Ronald J Headid
- School of Health and Kinesiology, University of Nebraska at Omaha, Omaha, Nebraska
| | - Elizabeth J Pekas
- School of Health and Kinesiology, University of Nebraska at Omaha, Omaha, Nebraska
| | - TeSean K Wooden
- School of Health and Kinesiology, University of Nebraska at Omaha, Omaha, Nebraska
| | - Won-Mok Son
- School of Health and Kinesiology, University of Nebraska at Omaha, Omaha, Nebraska
| | - Gwenael Layec
- Department of Kinesiology, University of Massachusetts, Amherst, Massachusetts.,Institute for Applied Life Sciences, University of Massachusetts, Amherst, Massachusetts
| | - John Shin
- Wiess School of Natural Sciences, Rice University, Houston, Texas
| | - Song-Young Park
- School of Health and Kinesiology, University of Nebraska at Omaha, Omaha, Nebraska
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10
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Kapil V, Khambata RS, Jones DA, Rathod K, Primus C, Massimo G, Fukuto JM, Ahluwalia A. The Noncanonical Pathway for In Vivo Nitric Oxide Generation: The Nitrate-Nitrite-Nitric Oxide Pathway. Pharmacol Rev 2020; 72:692-766. [DOI: 10.1124/pr.120.019240] [Citation(s) in RCA: 69] [Impact Index Per Article: 17.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
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11
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Okushima D, Poole DC, Barstow TJ, Kondo N, Chin LMK, Koga S. Effect of differential muscle activation patterns on muscle deoxygenation and microvascular haemoglobin regulation. Exp Physiol 2020; 105:531-541. [PMID: 31944446 PMCID: PMC10466155 DOI: 10.1113/ep088322] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2019] [Accepted: 01/14/2020] [Indexed: 11/08/2022]
Abstract
NEW FINDINGS What is the central question of this study? Does the presence and extent of heterogeneity in the ratio of O2 delivery to uptake across human muscles relate specifically to different muscle activation patterns? What is the main finding and its importance? During ramp incremental knee-extension and cycling exercise, the profiles of muscle deoxygenation (deoxy[haemoglobin + myoglobin]) and diffusive O2 potential (total[haemoglobin + myoglobin]) in the vastus lateralis corresponded to different muscle activation strategies. However, this was not the case for the rectus femoris, where muscle activation and deoxygenation profiles were dissociated and might therefore be determined by other structural and/or functional attributes (e.g. arteriolar vascular regulation and control of red blood cell flux). ABSTRACT Near-infrared spectroscopy has revealed considerable heterogeneity in the ratio of O2 delivery to uptake as identified by disparate deoxygenation {deoxy[haemoglobin + myoglobin] (deoxy[Hb + Mb])} values in the exercising quadriceps. However, whether this represents a recruitment phenomenon or contrasting vascular and metabolic control, as seen among fibre types, has not been established. We used knee-extension (KE) and cycling (CE) incremental exercise protocols to examine whether differential muscle activation profiles could account for the heterogeneity of deoxy[Hb + Mb] and microvascular haemoconcentration (i.e. total[Hb + Mb]). Using time-resolved near-infrared spectroscopy for the quadriceps femoris (vastus lateralis and rectus femoris) during exhaustive ramp exercise in eight participants, we tested the following hypotheses: (i) the deoxy[Hb + Mb] (i.e. fractional O2 extraction) would relate to muscle activation levels across exercise protocols; and (ii) KE would induce greater total[Hb + Mb] (i.e. diffusive O2 potential) at task failure (i.e. peak O2 uptake) than CE irrespective of muscle site. At a given level of muscle activation, as assessed by the relative integrated EMG normalized to maximal voluntary contraction (%iEMGmax ), the vastus lateralis deoxy[Hb + Mb] profile was not different between exercise protocols. However, at peak O2 uptake and until 20% iEMGmax for CE, rectus femoris exhibited a lower deoxy[Hb + Mb] (83.2 ± 15.5 versus 98.2 ± 19.4 μm) for KE than for CE (P < 0.05). The total[Hb + Mb] at peak O2 uptake was not different between exercise protocols for either muscle site. These data support the hypothesis that the contrasting patterns of convective and diffusive O2 transport correspond to different muscle activation patterns in vastus lateralis but not rectus femoris. Thus, the differential deoxygenation profiles for rectus femoris across exercise protocols might be dependent upon specific facets of muscle architecture and functional haemodynamic events.
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Affiliation(s)
- Dai Okushima
- Applied Physiology Laboratory, Kobe Design University, Kobe, Hyogo, Japan
- Research Fellow of Japan Society for the Promotion of Science, Tokyo, Japan
- Osaka International University, Moriguchi, Japan
| | - David C. Poole
- Departments of Kinesiology and Anatomy and Physiology, Kansas State University, Manhattan, Kansas
| | - Thomas J. Barstow
- Departments of Kinesiology and Anatomy and Physiology, Kansas State University, Manhattan, Kansas
| | | | - Lisa M. K. Chin
- Rehabilitation Medicine Department, National Institutes of Health Clinical Center, Bethesda, Maryland
| | - Shunsaku Koga
- Applied Physiology Laboratory, Kobe Design University, Kobe, Hyogo, Japan
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12
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Wakabayashi H, Osawa M, Koga S, Li K, Sakaue H, Sengoku Y, Takagi H. Effects of muscle cooling on kinetics of pulmonary oxygen uptake and muscle deoxygenation at the onset of exercise. Physiol Rep 2019; 6:e13910. [PMID: 30381894 PMCID: PMC6209689 DOI: 10.14814/phy2.13910] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2018] [Accepted: 10/03/2018] [Indexed: 11/24/2022] Open
Abstract
This study investigated effects of skeletal muscle cooling on the metabolic response and kinetics of pulmonary oxygen uptake (V˙O2) and skeletal muscle deoxygenation during submaximal exercise. In the cooling condition (C), after immersion of the lower body into 12°C water for 30 min, eight healthy males performed 30‐min cycling exercise at the lactate threshold while undergoing thigh cooling by a water‐circulating pad. In the normal condition (N) as control, they conducted the same exercise protocol without cooling. Blood lactate concentration was significantly higher in C than N at 10 min after onset of exercise (4.0 ± 1.7 and 2.4 ± 1.2 mmol/L in C and N, P < 0.05). The percent change in the tissue oxygen saturation of the vastus lateralis, measured by a near‐infrared spectroscopy, was significantly lower in C at 2, 8, 10, and 20 min after the exercise onset compared with N (P < 0.05). The percent change in deoxy hemoglobin+myoglobin concentration (Deoxy[Hb+Mb]) showed a transient peak at the onset of exercise and significantly higher value in C at 10, 20, and 30 min after the exercise onset (P < 0.05). Compared to N, slower V˙O2 kinetics (mean response time) was observed in C (45.6 ± 7.8 and 36.1 ± 7.7 sec in C and N, P < 0.05). The mean response time in C relative to N was significantly correlated with the transient peak of Deoxy[Hb+Mb] in C (r = 0.84, P < 0.05). These results suggest that lower oxygen delivery to the hypothermic skeletal muscle might induce greater glycolytic metabolism during exercise and slower V˙O2 kinetics at the onset of exercise.
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Affiliation(s)
| | - Mizuki Osawa
- Faculty of Health and Sport Sciences, University of Tsukuba, Tsukuba, Japan
| | - Shunsaku Koga
- Applied Physiology Laboratory, Kobe Design University, Kobe, Japan
| | - Ke Li
- Faculty of Health and Sport Sciences, University of Tsukuba, Tsukuba, Japan
| | - Hiroyuki Sakaue
- Faculty of Health and Sport Sciences, University of Tsukuba, Tsukuba, Japan
| | - Yasuo Sengoku
- Faculty of Health and Sport Sciences, University of Tsukuba, Tsukuba, Japan
| | - Hideki Takagi
- Faculty of Health and Sport Sciences, University of Tsukuba, Tsukuba, Japan
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13
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Breese BC, Saynor ZL, Barker AR, Armstrong N, Williams CA. Relationship between (non)linear phase II pulmonary oxygen uptake kinetics with skeletal muscle oxygenation and age in 11-15 year olds. Exp Physiol 2019; 104:1929-1941. [PMID: 31512297 DOI: 10.1113/ep087979] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2019] [Accepted: 09/09/2019] [Indexed: 12/28/2022]
Abstract
NEW FINDINGS What is the central question of this study? Do the phase II parameters of pulmonary oxygen uptake ( V ̇ O 2 ) kinetics display linear, first-order behaviour in association with alterations in skeletal muscle oxygenation during step cycling of different intensities or when exercise is initiated from an elevated work rate in youths. What is the main finding and its importance? Both linear and non-linear features of phase II V ̇ O 2 kinetics may be determined by alterations in the dynamic balance between microvascular O2 delivery and utilization in 11-15 year olds. The recruitment of higher-order (i.e. type II) muscle fibres during 'work-to-work' cycling might be responsible for modulating V ̇ O 2 kinetics with chronological age. ABSTRACT This study investigated in 19 male youths (mean age: 13.6 ± 1.1 years, range: 11.7-15.7 years) the relationship between pulmonary oxygen uptake ( V ̇ O 2 ) and muscle deoxygenation kinetics during moderate- and very heavy-intensity 'step' cycling initiated from unloaded pedalling (i.e. U → M and U → VH) and moderate to very heavy-intensity step cycling (i.e. M → VH). Pulmonary V ̇ O 2 was measured breath-by-breath along with the tissue oxygenation index (TOI) of the vastus lateralis using near-infrared spectroscopy. There were no significant differences in the phase II time constant ( τ V ̇ O 2 p ) between U → M and U → VH (23 ± 6 vs. 25 ± 7 s; P = 0.36); however, the τ V ̇ O 2 p was slower during M → VH (42 ± 16 s) compared to other conditions (P < 0.001). Quadriceps TOI decreased with a faster (P < 0.01) mean response time (MRT; i.e. time delay + τ) during U → VH (14 ± 2 s) compared to U → M (22 ± 4 s) and M → VH (20 ± 6 s). The difference (Δ) between the τ V ̇ O 2 p and MRT-TOI was greater during U → VH compared to U → M (12 ± 7 vs. 2 ± 7 s, P < 0.001) and during M → VH (23 ± 15 s) compared to other conditions (P < 0.02), suggesting an increased proportional speeding of fractional O2 extraction. The slowing of the τ V ̇ O 2 p during M → VH relative to U → M and U → VH correlated positively with chronological age (r = 0.68 and 0.57, respectively, P < 0.01). In youths, 'work-to-work' transitions slowed microvascular O2 delivery-to-O2 utilization with alterations in phase II V ̇ O 2 dynamics accentuated between the ages of 11 and 15 years.
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Affiliation(s)
- Brynmor C Breese
- School of Biomedical Sciences, Faculty of Medicine and Dentistry, University of Plymouth, Plymouth, UK
| | - Zoe L Saynor
- Department of Sport and Exercise Science, Faculty of Science, University of Portsmouth, Portsmouth, UK
| | - Alan R Barker
- Children's Health and Exercise Research Centre, Sport and Health Sciences, College of Life and Environmental Sciences, University of Exeter, Exeter, UK
| | - Neil Armstrong
- Children's Health and Exercise Research Centre, Sport and Health Sciences, College of Life and Environmental Sciences, University of Exeter, Exeter, UK
| | - Craig A Williams
- Children's Health and Exercise Research Centre, Sport and Health Sciences, College of Life and Environmental Sciences, University of Exeter, Exeter, UK
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Fuglestad MA, Hernandez H, Gao Y, Ybay H, Schieber MN, Brunette KE, Myers SA, Casale GP, Pipinos II. A low-cost, wireless near-infrared spectroscopy device detects the presence of lower extremity atherosclerosis as measured by computed tomographic angiography and characterizes walking impairment in peripheral artery disease. J Vasc Surg 2019; 71:946-957. [PMID: 31445826 DOI: 10.1016/j.jvs.2019.04.493] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2019] [Accepted: 04/28/2019] [Indexed: 01/14/2023]
Abstract
BACKGROUND Patients with peripheral artery disease (PAD) who experience intermittent claudication report a range of symptoms. Patients with symptoms other than classically described intermittent claudication may be at the highest risk for functional decline and mobility loss. Therefore, technologies allowing for characterization of PAD severity are desirable. Near-infrared spectroscopy (NIRS) allows for measurements of muscle heme oxygen saturation (StO2) during exercise. We hypothesized lower extremities affected by PAD would exhibit distinct NIRS profiles as measured by a low-cost, wireless NIRS device and that NIRS during exercise predicts walking limitation. METHODS We recruited 40 patients with PAD and 10 control participants. All patients with PAD completed a computed tomographic angiography, 6-minute walk test, and a standardized treadmill test. Controls completed a 540-second treadmill test for comparison. StO2 measurements were continuously taken from the gastrocnemius during exercise. Variables were analyzed by Fischer's exact, χ2, Wilcoxon rank-sum, and Kruskal-Wallis tests as appropriate. Correlations were assessed by partial Spearman correlation coefficients adjusted for occlusive disease pattern. RESULTS Patients with PAD experienced claudication onset at a median of 108 seconds with a median peak walking time of 288 seconds. The baseline StO2 was similar between PAD and control. The StO2 of PAD and control participants dropped below baseline at a median of 1 and 104 seconds of exercise, respectively (P < .0001). Patients with PAD reached minimum StO2 earlier than control participants (119 seconds vs 522 seconds, respectively; P < .001) and experienced a greater change in StO2 at 1 minute of exercise (-73.2% vs 8.3%; P < .0001) and a greater decrease at minimum exercise StO2 (-83.4% vs -16.1%; P < .0001). For patients with PAD, peak walking time, and 6-minute walking distance correlated with percent change in StO2 at 1 minute of exercise (r = -0.76 and -0.67, respectively; P < .001) and time to minimum StO2 (r = 0.79 and 0.70, respectively; P < .0001). CONCLUSIONS In this initial evaluation of a novel, low-cost NIRS device, lower extremities affected by PAD exhibited characteristic changes in calf muscle StO2, which differentiated them from healthy controls and were strongly correlated with walking impairment. These findings confirm and expand on previous work demonstrating the potential clinical value of NIRS devices and the need for further research investigating the ability of low-cost NIRS technology to evaluate, diagnose, and monitor treatment response in PAD.
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Affiliation(s)
| | - Hernan Hernandez
- Department of Surgery, University of Nebraska Medical Center, Omaha, Neb
| | - Yue Gao
- Department of Surgery, University of Nebraska Medical Center, Omaha, Neb
| | - Henamari Ybay
- Department of Biomechanics, University of Nebraska at Omaha, Omaha, Neb
| | - Molly N Schieber
- Department of Biomechanics, University of Nebraska at Omaha, Omaha, Neb
| | | | - Sara A Myers
- Department of Biomechanics, University of Nebraska at Omaha, Omaha, Neb
| | - George P Casale
- Department of Surgery, University of Nebraska Medical Center, Omaha, Neb
| | - Iraklis I Pipinos
- Department of Surgery, University of Nebraska Medical Center, Omaha, Neb; Department of Biomechanics, University of Nebraska at Omaha, Omaha, Neb; Department of Surgery, Veterans Affairs Medical Center, Omaha, Neb.
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15
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Gildea N, Rocha J, McDermott A, O'Shea D, Green S, Egaña M. Influence of type 2 diabetes on muscle deoxygenation during ramp incremental cycle exercise. Respir Physiol Neurobiol 2019; 269:103258. [PMID: 31349019 DOI: 10.1016/j.resp.2019.103258] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2019] [Revised: 07/04/2019] [Accepted: 07/23/2019] [Indexed: 11/18/2022]
Abstract
We tested the hypothesis that type 2 diabetes (T2D) alters the profile of muscle fractional oxygen (O2) extraction (near-infrared spectroscopy) during incremental cycle exercise. Seventeen middle-aged individuals with uncomplicated T2D and 17 controls performed an upright ramp test to exhaustion. The rate of muscle deoxygenation (i.e. deoxygenated haemoglobin and myoglobin concentration, Δ[HHb+Mb]) profiles of the vastus lateralis muscle were normalised to 100% of the response, plotted against % power output (PO) and fitted with a double linear regression model. Peak oxygen uptake was significantly (P < 0.05) reduced in individuals with T2D. The %Δ[HHb+Mb]/%PO slope of the first linear segment of the double linear regression function was significantly (P < 0.05) steeper in T2D than controls (1.59 (1.14) vs 1.23 (0.51)). Both groups displayed a near-plateau in Δ[HHb+Mb] at an exercise intensity (%PO) not different amongst them. Such findings suggest that a reduced O2 delivery to active muscles is an important underlying cause of exercise intolerance during a maximum graded test in middle-aged individuals with T2D.
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Affiliation(s)
- Norita Gildea
- Department of Physiology, School of Medicine, Trinity College Dublin, Dublin, Ireland
| | - Joel Rocha
- Division of Sport and Exercise Sciences, Abertay University, Dundee, UK
| | - Adam McDermott
- Department of Physiology, School of Medicine, Trinity College Dublin, Dublin, Ireland
| | - Donal O'Shea
- Endocrinology, St Columcille's and St Vincent's Hospitals, Dublin, Ireland
| | - Simon Green
- School of Science and Health, Western Sydney University, Sydney, Australia
| | - Mikel Egaña
- Department of Physiology, School of Medicine, Trinity College Dublin, Dublin, Ireland.
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16
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Koga S, Okushima D, Poole DC, Rossiter HB, Kondo N, Barstow TJ. Unaltered V̇o 2 kinetics despite greater muscle oxygenation during heavy-intensity two-legged knee extension versus cycle exercise in humans. Am J Physiol Regul Integr Comp Physiol 2019; 317:R203-R213. [PMID: 31042412 DOI: 10.1152/ajpregu.00015.2019] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Relative perfusion of active muscles is greater during knee extension ergometry (KE) than cycle ergometry (CE). This provides the opportunity to investigate the effects of increased O2 delivery (Q̇o2) on deoxygenation heterogeneity among quadriceps muscles and pulmonary oxygen uptake (V̇o2) kinetics. Using time-resolved near-infrared spectroscopy, we hypothesized that compared with CE the superficial vastus lateralis (VL), superficial rectus femoris, and deep VL in KE would have 1) a smaller amplitude of the exercise-induced increase in deoxy[Hb + Mb] (related to the balance between V̇o2 and Q̇o2); 2) a greater amplitude of total[Hb + Mb] (related to the diffusive O2 conductance); 3) a greater homogeneity of regional muscle deoxy[Hb + Mb]; and 4) no difference in pulmonary V̇o2 kinetics. Eight participants performed square-wave KE and CE exercise from 20 W to heavy work rates. Deoxy[Hb + Mb] amplitude was less for all muscle regions in KE (P < 0.05: superficial, KE 17-24 vs. CE 19-40; deep, KE 19 vs. CE 26 μM). Furthermore, the amplitude of total[Hb + Mb] was greater for KE than CE at all muscle sites (P < 0.05: superficial, KE, 7-21 vs. CE, 1-16; deep, KE, 11 vs. CE, -3 μM). Although the amplitude and heterogeneity of deoxy[Hb + Mb] were significantly lower in KE than CE during the first minute of exercise, the pulmonary V̇o2 kinetics was not different for KE and CE. These data show that the microvascular Q̇o2 to V̇o2 ratio, and thus tissue oxygenation, was greater in KE than CE. This suggests that pulmonary and muscle V̇o2 kinetics in young healthy humans are not limited by Q̇o2 during heavy-intensity cycling.
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Affiliation(s)
- Shunsaku Koga
- Applied Physiology Laboratory, Kobe Design University , Kobe , Japan
| | - Dai Okushima
- Applied Physiology Laboratory, Kobe Design University , Kobe , Japan
| | - David C Poole
- Department of Anatomy and Physiology, College of Veterinary Medicine, Kansas State University , Manhattan, Kansas.,Department of Kinesiology, Kansas State University, Manhattan, Kansas
| | - Harry B Rossiter
- Rehabilitation Clinical Trials Center, Division of Respiratory and Critical Care Physiology and Medicine, Los Angeles Biomedical Research Institute at Harbor-University of California, Los Angeles Medical Center , Torrance, California.,Faculty of Biological Sciences, University of Leeds , Leeds , United Kingdom
| | - Narihiko Kondo
- Applied Physiology Laboratory, Kobe University , Kobe , Japan
| | - Thomas J Barstow
- Department of Kinesiology, Kansas State University, Manhattan, Kansas
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17
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Ribeiro F, Oueslati F, Saey D, Lépine PA, Chambah S, Coats V, Maltais F. Cardiorespiratory and Muscle Oxygenation Responses to Isokinetic Exercise in Chronic Obstructive Pulmonary Disease. Med Sci Sports Exerc 2018; 51:841-849. [PMID: 30531487 DOI: 10.1249/mss.0000000000001856] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
PURPOSE This study aimed to describe cardiorespiratory, quadriceps oxygenation, and muscle fatigue responses during a one-legged quadriceps isokinetic endurance exercise in chronic obstructive pulmonary disease (COPD) and control subjects. METHODS Fourteen patients with COPD and 14 control subjects performed a cardiopulmonary cycling exercise test to exhaustion to assess peak oxygen consumption (V˙O2peak), minute ventilation (V˙Epeak), and heart rate (HRpeak). They also performed a quadriceps isokinetic endurance exercise consisting in 30 maximal knee extensions at 90°·s with continuous monitoring of expired gases, cardiac output, and oxygenation of the quadriceps by near-infrared spectroscopy. Total muscle work and fatigue index were also quantified. RESULTS The total muscle work developed during the quadriceps isokinetic endurance exercise was 2.25 ± 0.57 kJ in COPD and 3.12 ± 0.60 kJ in controls, P < 0.001. In absolute terms, there were no between-group differences in V˙O2, V˙E, cardiac output, and HR at the end of quadriceps isokinetic endurance exercise. However, V˙E and HR reported that a fraction of their respective peak values during cardiopulmonary cycling exercise test were higher in COPD (V˙E/V˙Epeak, 69% ± 3%; HR/HRpeak, 82% ± 15%) compared with controls (V˙E/V˙Epeak, 45% ± 2%; HR/HRpeak, 71% ± 13%), all P < 0.05. During quadriceps isokinetic endurance exercise, quadriceps deoxyhemoglobin increased by 47% ± 31% in patients versus 33% ± 41% in controls (P < 0.05 from rest values) with a significant between-group differences (P = 0.025). The fatigue index during the quadriceps exercise was higher in COPD compared with controls. CONCLUSIONS Although one-legged quadriceps isokinetic endurance exercise resulted in substantial central cardiorespiratory demands in COPD, this exercise was nevertheless associated with muscle overload as evidenced by muscle deoxygenation and higher muscle fatigue index in COPD compared with controls. These findings may have implications of the design of exercise training programs in COPD.
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Affiliation(s)
- Fernanda Ribeiro
- Institut Universitaire de Cardiologie et de Pneumologie de Québec, Université Laval, Québec, Québec, CANADA
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18
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Layec G, Trinity JD, Hart CR, Le Fur Y, Zhao J, Reese V, Jeong EK, Richardson RS. Impaired Muscle Efficiency but Preserved Peripheral Hemodynamics and Mitochondrial Function With Advancing Age: Evidence From Exercise in the Young, Old, and Oldest-Old. J Gerontol A Biol Sci Med Sci 2018; 73:1303-1312. [PMID: 29584857 PMCID: PMC6132121 DOI: 10.1093/gerona/gly050] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2017] [Accepted: 03/20/2018] [Indexed: 12/17/2022] Open
Abstract
Muscle weakness in the elderly has been linked to recurrent falls and morbidity; therefore, elucidating the mechanisms contributing to the loss of muscle function and mobility with advancing age is critical. To this aim, we comprehensively examined skeletal muscle metabolic function and hemodynamics in 11 young (23 ± 2 years), 11 old (68 ± 2 years), and 10 oldest-old (84 ± 2 years) physical activity-matched participants. Specifically, oxidative stress markers, mitochondrial function, and the ATP cost of contraction as well as peripheral hemodynamics were assessed during dynamic plantar flexion exercise at 40 per cent of maximal work rate (WRmax). Both the PCr recovery time constant and the peak rate of mitochondrial ATP synthesis were not significantly different between groups. In contrast, the ATP cost of dynamic contractions (young: 1.5 ± 1.0, old: 3.4 ± 2.1, oldest-old: 6.1 ± 3.6 mM min-1 W-1) and systemic markers of oxidative stress were signficantly increased with age, with the ATP cost of contraction being negatively correlated with WRmax (r = .59, p < .05). End-of-exercise blood flow per Watt rose significantly with increasing age (young: 37 ± 20, old: 82 ± 68, oldest-old: 154 ± 93 mL min-1 W-1). These findings suggest that the progressive deterioration of muscle contractile efficiency with advancing age may play an important role in the decline in skeletal muscle functional capacity in the elderly.
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Affiliation(s)
- Gwenael Layec
- Department of Medicine, Division of Geriatrics, University of Utah, Salt Lake City, Utah
- Geriatric Research, Education, and Clinical Center, George E. Whalen VA Medical Center, Salt Lake City, Utah
- Department of Nutrition and Integrative Physiology, University of Utah, Salt Lake City, Utah
| | - Joel D Trinity
- Department of Medicine, Division of Geriatrics, University of Utah, Salt Lake City, Utah
- Geriatric Research, Education, and Clinical Center, George E. Whalen VA Medical Center, Salt Lake City, Utah
- Department of Nutrition and Integrative Physiology, University of Utah, Salt Lake City, Utah
| | - Corey R Hart
- Department of Medicine, Division of Geriatrics, University of Utah, Salt Lake City, Utah
- Geriatric Research, Education, and Clinical Center, George E. Whalen VA Medical Center, Salt Lake City, Utah
- Department of Exercise and Sport Science, University of Utah, Salt Lake City, Utah
| | - Yann Le Fur
- Aix-Marseille Université, CNRS, CRMBM, UMR, Marseille, France
| | - Jia Zhao
- Department of Medicine, Division of Geriatrics, University of Utah, Salt Lake City, Utah
| | - Van Reese
- Department of Medicine, Division of Geriatrics, University of Utah, Salt Lake City, Utah
| | - Eun-Kee Jeong
- Department of Radiology and Utah Center for Advanced Imaging Research, University of Utah, Salt Lake City, Utah
| | - Russell S Richardson
- Department of Medicine, Division of Geriatrics, University of Utah, Salt Lake City, Utah
- Geriatric Research, Education, and Clinical Center, George E. Whalen VA Medical Center, Salt Lake City, Utah
- Department of Nutrition and Integrative Physiology, University of Utah, Salt Lake City, Utah
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19
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Niemeijer VM, Snijders T, Verdijk LB, van Kranenburg J, Groen BBL, Holwerda AM, Spee RF, Wijn PFF, van Loon LJC, Kemps HMC. Skeletal muscle fiber characteristics in patients with chronic heart failure: impact of disease severity and relation with muscle oxygenation during exercise. J Appl Physiol (1985) 2018; 125:1266-1276. [PMID: 30091667 DOI: 10.1152/japplphysiol.00057.2018] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
INTRODUCTION Skeletal muscle function in patients with heart failure and reduced ejection fraction (HFrEF) greatly determines exercise capacity. However, reports on skeletal muscle fiber dimensions, fiber capillarization, and their physiological importance are inconsistent. METHODS Twenty-five moderately-impaired patients with HFrEF and 25 healthy control (HC) subjects underwent muscle biopsy sampling. Type I and type II muscle fiber characteristics were determined by immunohistochemistry. In patients with HFrEF, enzymatic oxidative capacity was assessed, and pulmonary oxygen uptake (VO2) and skeletal muscle oxygenation during maximal and moderate-intensity exercise were measured using near-infrared spectroscopy. RESULTS While muscle fiber cross-sectional area (CSA) was not different between patients with HFrEF and HC, percentage of type I fibers was higher in HC (46±15% versus 37±12%, respectively, P=0.041). Fiber type distribution and CSA were not different between patients in New York Heart Association (NYHA) class II and III. Type I muscle fiber capillarization was higher in HFrEF compared with controls (capillary-to-fiber perimeter exchange (CFPE) index: 5.70±0.92 versus 5.05±0.82, respectively, P=0.027). Patients in NYHA class III had slower VO2 and muscle deoxygenation kinetics during onset of exercise, and lower muscle oxidative capacity than those in class II (P<0.05). Also, fiber capillarization was lower, but not compared with HC. Higher CFPE index was related to faster deoxygenation (rspearman=-0.682, P=0.001), however, not to muscle oxidative capacity (r=-0.282, P=0.216). CONCLUSIONS Type I muscle fiber capillarization is higher in HFrEF compared with HC, but not in patients with greater exercise impairment. Greater capillarization may positively affect VO2 kinetics by enhancing muscle oxygen diffusion.
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Affiliation(s)
- Victor M Niemeijer
- Department of Cardiology, Máxima Medical Centre, Veldhoven, the Netherlands, Netherlands
| | - Tim Snijders
- Human Movement Sciences, Maastricht University Medical Centre+, Netherlands
| | - Lex B Verdijk
- Human Movement Sciences, Maastricht University Medical Centre, Netherlands
| | - Janneau van Kranenburg
- Human Movement Sciences, NUTRIM School for Nutrition, Toxicology and Metabolism, Maastricht University Medical Centre+ (MUMC+)
| | - Bart B L Groen
- Department of Human Movement Sciences, Maastricht University Medical Centre, Netherlands
| | | | - Ruud F Spee
- Department of Cardiology, Maxima Medical Center, Netherlands
| | - Pieter F F Wijn
- Department of Applied Physics, Eindhoven University of Technology
| | - Luc J C van Loon
- NUTRIM School of Nutrition and Translational Research in Metabolism, Maastricht University Medical Centre, Netherlands
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20
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Craig JC, Broxterman RM, Smith JR, Allen JD, Barstow TJ. Effect of dietary nitrate supplementation on conduit artery blood flow, muscle oxygenation, and metabolic rate during handgrip exercise. J Appl Physiol (1985) 2018; 125:254-262. [DOI: 10.1152/japplphysiol.00772.2017] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
Dietary nitrate supplementation has positive effects on mitochondrial and muscle contractile efficiency during large muscle mass exercise in humans and on skeletal muscle blood flow (Q̇) in rats. However, concurrent measurement of these effects has not been performed in humans. Therefore, we assessed the influence of nitrate supplementation on Q̇ and muscle oxygenation characteristics during moderate- (40 %peak) and severe-intensity(85% peak) handgrip exercise in a randomized, double-blind, crossover design. Nine healthy men (age: 25 ± 2 yr) completed four constant-power exercise tests (2/intensity) randomly assigned to condition [nitrate-rich (nitrate) or nitrate-poor (placebo) beetroot supplementation] and intensity (40 or 85% peak). Resting mean arterial pressure was lower after nitrate compared with placebo (84 ± 4 vs. 89 ± 4 mmHg, P < 0.01). All subjects were able to sustain 10 min of exercise at 40% peak in both conditions. Nitrate had no effect on exercise tolerance during 85% peak (nitrate: 358 ± 29; placebo: 341 ± 34 s; P = 0.3). Brachial artery Q̇ was not different after nitrate at rest or any time during exercise. Deoxygenated [hemoglobin + myoglobin] was not different for 40% peak ( P > 0.05) but was elevated throughout 85% peak ( P < 0.05) after nitrate. The metabolic cost (V̇o2) was not different at the end of exercise; however, the V̇o2 primary amplitude at the onset of exercise was elevated after nitrate for the 85% peak work rate (96 ± 20 vs. 72 ± 12 ml/min, P < 0.05) and had a faster response. These findings suggest that an acute dose of nitrate reduces resting blood pressure and speeds V̇o2 kinetics in young adults but does not augment Q̇ or reduce steady-state V̇o2 during small muscle mass handgrip exercise. NEW & NOTEWORTHY We show that acute dietary nitrate supplementation via beetroot juice increases the amplitude and speed of local muscle V̇o2 on kinetics parameters during severe- but not moderate-intensity handgrip exercise. These changes were found in the absence of an increased blood flow response, suggesting that the increased V̇o2 was attained via improvements in fractional O2 extraction and/or spatial distribution of blood flow within the exercising muscle.
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Affiliation(s)
- Jesse C. Craig
- Department of Kinesiology, Kansas State University, Manhattan, Kansas
| | - Ryan M. Broxterman
- Department of Kinesiology, Kansas State University, Manhattan, Kansas
- Department of Anatomy and Physiology, Kansas State University, Manhattan, Kansas
| | - Joshua R. Smith
- Department of Kinesiology, Kansas State University, Manhattan, Kansas
| | - Jason D. Allen
- Department of Medicine, Duke University Medical Center, Durham, North Carolina
- Department of Kinesiology, University of Virginia, Charlottesville, Virginia
| | - Thomas J. Barstow
- Department of Kinesiology, Kansas State University, Manhattan, Kansas
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21
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Nakajima T, Koide S, Yasuda T, Hasegawa T, Yamasoba T, Obi S, Toyoda S, Nakamura F, Inoue T, Poole DC, Kano Y. Muscle hypertrophy following blood flow-restricted, low-force isometric electrical stimulation in rat tibialis anterior: role for muscle hypoxia. J Appl Physiol (1985) 2018; 125:134-145. [DOI: 10.1152/japplphysiol.00972.2017] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Low-force exercise training with blood flow restriction (BFR) elicits muscle hypertrophy as seen typically after higher-force exercise. We investigated the effects of microvascular hypoxia [i.e., low microvascular O2 partial pressures (P mvO2)] during contractions on muscle hypertrophic signaling, growth response, and key muscle adaptations for increasing exercise capacity. Wistar rats were fitted with a cuff placed around the upper thigh and inflated to restrict limb blood flow. Low-force isometric contractions (30 Hz) were evoked via electrical stimulation of the tibialis anterior (TA) muscle. The P mvO2 was determined by phosphorescence quenching. Rats underwent acute and chronic stimulation protocols. Whereas P mvO2 decreased transiently with 30 Hz contractions, simultaneous BFR induced severe hypoxia, reducing P mvO2 lower than present for maximal (100 Hz) contractions. Low-force electrical stimulation (EXER) induced muscle hypertrophy (6.2%, P < 0.01), whereas control group conditions or BFR alone did not. EXER+BFR also induced an increase in muscle mass (11.0%, P < 0.01) and, unique among conditions studied, significantly increased fiber cross-sectional area in the superficial TA ( P < 0.05). Phosphorylation of ribosomal protein S6 was enhanced by EXER+BFR, as were peroxisome proliferator-activated receptor gamma coactivator-1α and glucose transporter 4 protein levels. Fibronectin type III domain-containing protein 5, cytochrome c oxidase subunit 4, monocarboxylate transporter 1 (MCT1), and cluster of differentiation 147 increased with EXER alone. EXER+BFR significantly increased MCT1 expression more than EXER alone. These data demonstrate that microvascular hypoxia during contractions is not essential for hypertrophy. However, hypoxia induced via BFR may potentiate the muscle hypertrophic response (as evidenced by the increased superficial fiber cross-sectional area) with increased glucose transporter and mitochondrial biogenesis, which contributes to the pleiotropic effects of exercise training with BFR that culminate in an improved capacity for sustained exercise. NEW & NOTEWORTHY We investigated the effects of low microvascular O2 partial pressures (P mvO2) during contractions on muscle hypertrophic signaling and key elements in the muscle adaptation for increasing exercise capacity. Although demonstrating that muscle hypoxia is not obligatory for the hypertrophic response to low-force, electrically induced muscle contractions, the reduced P mvO2 enhanced ribosomal protein S6 phosphorylation and potentiated the hypertrophic response. Furthermore, contractions with blood flow restriction increased oxidative capacity, glucose transporter, and mitochondrial biogenesis, which are key determinants of the pleiotropic effects of exercise training.
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Affiliation(s)
- Toshiaki Nakajima
- Department of Cardiovascular Medicine, Dokkyo Medical University and Heart Center, Dokkyo Medical University Hospital, Tochigi, Japan
| | - Seiichiro Koide
- Bioscience and Technology Program, Department of Engineering Science, University of Electro-Communications, Tokyo, Japan
| | - Tomohiro Yasuda
- School of Nursing, Seirei Christopher University, Shizuoka, Japan
| | - Takaaki Hasegawa
- Department of Cardiovascular Medicine, Dokkyo Medical University and Heart Center, Dokkyo Medical University Hospital, Tochigi, Japan
| | | | - Syotaro Obi
- Department of Cardiovascular Medicine and Research Support Center, Dokkyo Medical University, Tochigi, Japan
| | - Shigeru Toyoda
- Department of Cardiovascular Medicine, Dokkyo Medical University and Heart Center, Dokkyo Medical University Hospital, Tochigi, Japan
| | - Fumitaka Nakamura
- Third Department of Internal Medicine, Teikyo University Chiba Medical Center, Chiba, Japan
| | - Teruo Inoue
- Department of Cardiovascular Medicine, Dokkyo Medical University and Heart Center, Dokkyo Medical University Hospital, Tochigi, Japan
| | - David C. Poole
- Department of Anatomy, Physiology and Kinesiology, Kansas State University, Manhattan, Kansas
| | - Yutaka Kano
- Bioscience and Technology Program, Department of Engineering Science, University of Electro-Communications, Tokyo, Japan
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22
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Koga S, Okushima D, Barstow TJ, Rossiter HB, Kondo N, Poole DC. Near-infrared spectroscopy of superficial and deep rectus femoris reveals markedly different exercise response to superficial vastus lateralis. Physiol Rep 2018; 5:5/17/e13402. [PMID: 28912130 PMCID: PMC5599862 DOI: 10.14814/phy2.13402] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2017] [Revised: 08/08/2017] [Accepted: 08/08/2017] [Indexed: 12/13/2022] Open
Abstract
To date our knowledge of skeletal muscle deoxygenation as measured by near-infrared spectroscopy (NIRS) is predicated almost exclusively on sampling of superficial muscle(s), most commonly the vastus lateralis (VL-s). Recently developed high power NIRS facilitates simultaneous sampling of deep (i.e., rectus femoris, RF-d) and superficial muscles of RF (RF-s) and VL-s. Because deeper muscle is more oxidative with greater capillarity and sustains higher blood flows than superficial muscle, we used time-resolved NIRS to test the hypotheses that, following exercise onset, the RF-d has slower deoxy[Hb+Mb] kinetics with reduced amplitude than superficial muscles. Thirteen participants performed cycle exercise transitions from unloaded to heavy work rates. Within the same muscle (RF-s vs. RF-d) deoxy[Hb+Mb] kinetics (mean response time, MRT) and amplitudes were not different. However, compared with the kinetics of VL-s, deoxy[Hb+Mb] of RF-s and RF-d were slower (MRT: RF-s, 51 ± 23; RF-d, 55 ± 29; VL-s, 18 ± 6 s; P < 0.05). Moreover, the amplitude of total[Hb+Mb] was greater for VL-s than both RF-s and RF-d (P < 0.05). Whereas pulmonary V˙O2 kinetics (i.e., on vs. off) were symmetrical in heavy exercise, there was a marked on-off asymmetry of deoxy[Hb+Mb] for all three sites i.e., MRT-off > MRT-on (P < 0.05). Collectively these data reveal profoundly different O2 transport strategies, with the RF-s and RF-d relying proportionately more on elevated perfusive and the VL-s on diffusive O2 transport. These disparate O2 transport strategies and their temporal profiles across muscles have previously been concealed within the "global" pulmonary V˙O2 response.
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Affiliation(s)
- Shunsaku Koga
- Applied Physiology Laboratory, Kobe Design University, Kobe, Japan
| | - Dai Okushima
- Applied Physiology Laboratory, Kobe Design University, Kobe, Japan
| | - Thomas J Barstow
- Departments of Anatomy and Physiology, and Kinesiology, Kansas State University, Manhattan, Kansas
| | - Harry B Rossiter
- Rehabilitation Clinical Trials Center, Division of Respiratory & Critical Care Physiology & Medicine, Los Angeles Biomedical Research Institute at Harbor-UCLA Medical Center, Torrance, California.,Faculty of Biological Sciences, University of Leeds, Leeds, United Kingdom
| | - Narihiko Kondo
- Applied Physiology Laboratory, Kobe University, Kobe, Japan
| | - David C Poole
- Departments of Anatomy and Physiology, and Kinesiology, Kansas State University, Manhattan, Kansas
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23
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Breese BC, Poole DC, Okushima D, Bailey SJ, Jones AM, Kondo N, Amano T, Koga S. The effect of dietary nitrate supplementation on the spatial heterogeneity of quadriceps deoxygenation during heavy-intensity cycling. Physiol Rep 2018; 5:5/14/e13340. [PMID: 28743821 PMCID: PMC5532482 DOI: 10.14814/phy2.13340] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2017] [Accepted: 05/23/2017] [Indexed: 12/31/2022] Open
Abstract
This study investigated the influence of dietary inorganic nitrate (NO3−) supplementation on pulmonary O2 uptake (V˙O2) and muscle deoxyhemoglobin/myoglobin (i.e. deoxy [Hb + Mb]) kinetics during submaximal cycling exercise. In a randomized, placebo‐controlled, cross‐over study, eight healthy and physically active male subjects completed two step cycle tests at a work rate equivalent to 50% of the difference between the gas exchange threshold and peak V˙O2 over separate 4‐day supplementation periods with NO3−‐rich (BR; providing 8.4 mmol NO3−∙day−1) and NO3−‐depleted (placebo; PLA) beetroot juice. Pulmonary V˙O2 was measured breath‐by‐breath and time‐resolved near‐infrared spectroscopy was utilized to quantify absolute deoxy [Hb + Mb] and total [Hb + Mb] within the rectus femoris, vastus lateralis, and vastus medialis. There were no significant differences (P > 0.05) in the primary deoxy [Hb + Mb] mean response time or amplitude between the PLA and BR trials at each muscle site. BR significantly increased the mean (three‐site) end‐exercise deoxy [Hb + Mb] (PLA: 91 ± 9 vs. BR: 95 ± 12 μmol/L, P < 0.05), with a tendency to increase the mean (three‐site) area under the curve for total [Hb + Mb] responses (PLA: 3650 ± 1188 vs. BR: 4467 ± 1315 μmol/L sec−1, P = 0.08). The V˙O2 slow component reduction after BR supplementation (PLA: 0.27 ± 0.07 vs. BR: 0.23 ± 0.08 L min−1, P = 0.07) correlated inversely with the mean increases in deoxy [Hb + Mb] and total [Hb + Mb] across the three muscle regions (r2 = 0.62 and 0.66, P < 0.05). Dietary NO3− supplementation increased O2 diffusive conductance across locomotor muscles in association with improved V˙O2 dynamics during heavy‐intensity cycling transitions.
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Affiliation(s)
- Brynmor C Breese
- School of Biomedical and Healthcare Sciences, Plymouth University, Plymouth, United Kingdom
| | - David C Poole
- Departments of Kinesiology and Anatomy and Physiology, Kansas State University, Manhattan, Kansas
| | - Dai Okushima
- Applied Physiology Laboratory, Kobe Design University, Kobe, Hyogo, Japan
| | - Stephen J Bailey
- School of Sport, Exercise and Health Sciences Loughborough University, Loughborough, United Kingdom
| | - Andrew M Jones
- Sport and Health Sciences, College of Life and Environmental Sciences University of Exeter, Exeter, United Kingdom
| | - Narihiko Kondo
- Faculty of Global Human Sciences, Kobe University, Kobe, Japan
| | - Tatsuro Amano
- Faculty of Education, Niigata University, Niigata, Japan
| | - Shunsaku Koga
- Applied Physiology Laboratory, Kobe Design University, Kobe, Hyogo, Japan
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24
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Arana C, Swanson B, Kuzyk SL. Probing under pressure: a look inside the compartmental haemodynamics of skeletal muscle during rest and contraction. J Physiol 2018; 596:2035-2036. [PMID: 29645273 DOI: 10.1113/jp276078] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Affiliation(s)
- Carolina Arana
- School of Health and Exercise Science, University of British Columbia, Kelowna, Canada
| | - Brittney Swanson
- School of Health and Exercise Science, University of British Columbia, Kelowna, Canada
| | - Samantha L Kuzyk
- School of Health and Exercise Science, University of British Columbia, Kelowna, Canada
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25
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Okushima D, Poole DC, Barstow TJ, Rossiter HB, Kondo N, Bowen TS, Amano T, Koga S. Greater V˙O2peak is correlated with greater skeletal muscle deoxygenation amplitude and hemoglobin concentration within individual muscles during ramp-incremental cycle exercise. Physiol Rep 2018; 4:4/23/e13065. [PMID: 27986837 PMCID: PMC5260088 DOI: 10.14814/phy2.13065] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2016] [Accepted: 11/03/2016] [Indexed: 11/24/2022] Open
Abstract
It is axiomatic that greater aerobic fitness (V˙O2peak) derives from enhanced perfusive and diffusive O2 conductances across active muscles. However, it remains unknown how these conductances might be reflected by regional differences in fractional O2 extraction (i.e., deoxy [Hb+Mb] and tissue O2 saturation [StO2]) and diffusive O2 potential (i.e., total[Hb+Mb]) among muscles spatially heterogeneous in blood flow, fiber type, and recruitment (vastus lateralis, VL; rectus femoris, RF). Using quantitative time‐resolved near‐infrared spectroscopy during ramp cycling in 24 young participants (V˙O2peak range: ~37.4–66.4 mL kg−1 min−1), we tested the hypotheses that (1) deoxy[Hb+Mb] and total[Hb+Mb] at V˙O2peak would be positively correlated with V˙O2peak in both VL and RF muscles; (2) the pattern of deoxygenation (the deoxy[Hb+Mb] slopes) during submaximal exercise would not differ among subjects differing in V˙O2peak. Peak deoxy [Hb+Mb] and StO2 correlated with V˙O2peak for both VL (r = 0.44 and −0.51) and RF (r = 0.49 and −0.49), whereas for total[Hb+Mb] this was true only for RF (r = 0.45). Baseline deoxy[Hb+Mb] and StO2 correlated with V˙O2peak only for RF (r = −0.50 and 0.54). In addition, the deoxy[Hb+Mb] slopes were not affected by aerobic fitness. In conclusion, while the pattern of deoxygenation (the deoxy[Hb+Mb] slopes) did not differ between fitness groups the capacity to deoxygenate [Hb+Mb] (index of maximal fractional O2 extraction) correlated significantly with V˙O2peak in both RF and VL muscles. However, only in the RF did total[Hb+Mb] (index of diffusive O2 potential) relate to fitness.
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Affiliation(s)
- Dai Okushima
- Applied Physiology Laboratory, Kobe Design University, Kobe, Japan
| | - David C Poole
- Departments of Kinesiology and Anatomy and Physiology, Kansas State University, Manhattan, Kansas
| | - Thomas J Barstow
- Departments of Kinesiology and Anatomy and Physiology, Kansas State University, Manhattan, Kansas
| | - Harry B Rossiter
- Rehabilitation Clinical Trials Center, Division of Respiratory & Critical Care Physiology & Medicine Los Angeles Biomedical Research Institute at Harbor-UCLA Medical Center, Torrance, California
| | - Narihiko Kondo
- Laboratory for Applied Human Physiology, Graduate School of Human Development and Environment Kobe University, Kobe, Japan
| | - T Scott Bowen
- Department of Internal Medicine & Cardiology, Heart Center, Leipzig University, Leipzig, Germany
| | - Tatsuro Amano
- Faculty of Education Niigata University, Niigata, Japan
| | - Shunsaku Koga
- Applied Physiology Laboratory, Kobe Design University, Kobe, Japan
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26
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Evidence of a metabolic reserve in the skeletal muscle of elderly people. Aging (Albany NY) 2017; 9:52-67. [PMID: 27824313 PMCID: PMC5310656 DOI: 10.18632/aging.101079] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2016] [Accepted: 10/20/2016] [Indexed: 11/25/2022]
Abstract
The purpose of the present study was to determine whether mitochondrial function is limited by O2 availability or the intrinsic capacity of mitochondria to synthesize ATP in elderly individuals. To this aim, we examined, in comparison to free-flow conditions (FF), the effect of superimposing reactive hyperemia (RH), induced by a period of brief ischemia during the last min of exercise, on O2 availability and mitochondrial function in the calf muscle. 12 healthy, untrained, elderly subjects performed dynamic plantar flexion exercise and phosphorus magnetic resonance spectroscopy (31P-MRS), near-infrared spectroscopy (NIRS), and Doppler ultrasound were used to assess muscle metabolism and peripheral hemodynamics. Limb blood flow [area under the curve (AUC), FF: 1.5±0.5L; RH: 3.2±1.1L, P<0.01] and convective O2 delivery (AUC, FF: 0.30±0.13L; RH: 0.64±0.29L, P<0.01) were significantly increased in RH in comparison to FF. RH was also associated with significantly higher capillary blood flow (P<0.05) and this resulted in a 33% increase in estimated peak mitochondrial ATP synthesis rate (FF: 24±11 mM.min−1; RH: 31±7 mM.min−1, P<0.05). These results document a hemodynamic reserve in the contracting calf muscle of the elderly accessible by superimposing reactive hyperemia. Furthermore, this increase in O2 availability enhanced mitochondrial function thus indicating a skeletal muscle metabolic reserve despite advancing age and low level of physical activity.
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27
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Watanabe A, Poole DC, Kano Y. The effects of RSR13 on microvascular Po2 kinetics and muscle contractile performance in the rat arterial ligation model of peripheral arterial disease. J Appl Physiol (1985) 2017; 123:764-772. [DOI: 10.1152/japplphysiol.00257.2017] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2017] [Revised: 05/17/2017] [Accepted: 06/08/2017] [Indexed: 01/12/2023] Open
Abstract
Exercise intolerance and claudication are symptomatic of peripheral arterial disease. There is a close relationship between muscle O2 delivery, microvascular oxygen partial pressure (P mvO2), and contractile performance. We therefore hypothesized that a reduction of hemoglobin-oxygen affinity via RSR13 would maintain a higher P mvO2 and enhance blood-muscle O2 transport and contractile function. In male Wistar rats (12 wk of age), we created hindlimb ischemia via right-side iliac artery ligation (AL). The contralateral (left) muscle served as control (CONT). Seven days after AL, phosphorescence-quenching techniques were used to measure P mvO2 at rest and during contractions (electrical stimulation; 1 Hz, 300 s) in tibialis anterior muscle (TA) under saline ( n = 10) or RSR13 ( n = 10) conditions. RSR13 at rest increased TA P mvO2 in CONT (13.9 ± 1.6 to 19.3 ± 1.9 Torr, P < 0.05) and AL (9.0 ± 0.5 to 9.9 ± 0.7 Torr, P < 0.05). Furthermore, RSR13 extended maintenance of the initial TA force (i.e., improved contractile performance) such that force was not decreased significantly until contraction 240 vs. 150 in CONT and 80 vs. 20 in AL. This improved muscle endurance with RSR13 was accompanied by a greater ΔP mvO2 (P mvO2 decrease from baseline) (CONT, 7.4 ± 1.0 to 11.2 ± 1.3; AL, 6.9 ± 0.5 to 8.6 ± 0.6 Torr, both P < 0.05). Whereas RSR13 did not alter the kinetics profile of P mvO2 (i.e., mean response time) substantially during contractions, muscle force was elevated, and the ratio of muscle force to P mvO2 increased. In conclusion, reduction of hemoglobin-oxygen affinity via RSR13 in AL increased P mvO2 and improved muscle contractile performance most likely via enhanced blood-muscle O2 diffusion. NEW & NOTEWORTHY This is the first investigation to examine the effect of RSR13 (erythrocyte allosteric effector) on skeletal muscle microvascular oxygen partial pressure kinetics and contractile function using an arterial ligation model of peripheral arterial disease in experimental animals. The present results provide strong support for the concept that reducing hemoglobin-O2 affinity via RSR13 improved tibialis anterior muscle contractile performance most likely via enhanced blood-muscle O2 diffusion.
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Affiliation(s)
- Aiko Watanabe
- Department of Engineering Science, University of Electro-Communications, Chofu, Tokyo, Japan; and
| | - David C. Poole
- Departments of Anatomy, Physiology and Kinesiology, Kansas State University, Manhattan, KS
| | - Yutaka Kano
- Department of Engineering Science, University of Electro-Communications, Chofu, Tokyo, Japan; and
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28
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Layec G, Hart CR, Trinity JD, Kwon OS, Rossman MJ, Broxterman RM, Le Fur Y, Jeong EK, Richardson RS. Oxygen delivery and the restoration of the muscle energetic balance following exercise: implications for delayed muscle recovery in patients with COPD. Am J Physiol Endocrinol Metab 2017; 313:E94-E104. [PMID: 28292763 PMCID: PMC6109703 DOI: 10.1152/ajpendo.00462.2016] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/22/2016] [Revised: 03/03/2017] [Accepted: 03/13/2017] [Indexed: 11/22/2022]
Abstract
Patients with chronic obstructive pulmonary disease (COPD) experience a delayed recovery from skeletal muscle fatigue following exhaustive exercise that likely contributes to their progressive loss of mobility. As this phenomenon is not well understood, this study sought to examine postexercise peripheral oxygen (O2) transport and muscle metabolism dynamics in patients with COPD, two important determinants of muscle recovery. Twenty-four subjects, 12 nonhypoxemic patients with COPD and 12 healthy subjects with a sedentary lifestyle, performed dynamic plantar flexion exercise at 40% of the maximal work rate (WRmax) with phosphorus magnetic resonance spectroscopy (31P-MRS), near-infrared spectroscopy (NIRS), and vascular Doppler ultrasound assessments. The mean response time of limb blood flow at the offset of exercise was significantly prolonged in patients with COPD (controls: 56 ± 27 s; COPD: 120 ± 87 s; P < 0.05). In contrast, the postexercise time constant for capillary blood flow was not significantly different between groups (controls: 49 ± 23 s; COPD: 51 ± 21 s; P > 0.05). The initial postexercise convective O2 delivery (controls: 0.15 ± 0.06 l/min; COPD: 0.15 ± 0.06 l/min) and the corresponding oxidative adenosine triphosphate (ATP) demand (controls: 14 ± 6 mM/min; COPD: 14 ± 6 mM/min) in the calf were not significantly different between controls and patients with COPD (P > 0.05). The phosphocreatine resynthesis time constant (controls: 46 ± 20 s; COPD: 49 ± 21 s), peak mitochondrial phosphorylation rate, and initial proton efflux were also not significantly different between groups (P > 0.05). Therefore, despite perturbed peripheral hemodynamics, intracellular O2 availability, proton efflux, and aerobic metabolism recovery in the skeletal muscle of nonhypoxemic patients with COPD are preserved following plantar flexion exercise and thus are unlikely to contribute to the delayed recovery from exercise in this population.
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Affiliation(s)
- Gwenael Layec
- Department of Medicine, Division of Geriatrics, University of Utah, Salt Lake City, Utah;
- Geriatric Research, Education, and Clinical Center, George E. Whalen Veterans Affairs Medical Center, Salt Lake City, Utah
- Department of Nutrition and Integrative Physiology, University of Utah, Salt Lake City, Utah
| | - Corey R Hart
- Geriatric Research, Education, and Clinical Center, George E. Whalen Veterans Affairs Medical Center, Salt Lake City, Utah
- Department of Exercise and Sport Science, University of Utah, Salt Lake City, Utah
| | - Joel D Trinity
- Department of Medicine, Division of Geriatrics, University of Utah, Salt Lake City, Utah
- Geriatric Research, Education, and Clinical Center, George E. Whalen Veterans Affairs Medical Center, Salt Lake City, Utah
- Department of Nutrition and Integrative Physiology, University of Utah, Salt Lake City, Utah
| | - Oh-Sung Kwon
- Department of Medicine, Division of Geriatrics, University of Utah, Salt Lake City, Utah
- Geriatric Research, Education, and Clinical Center, George E. Whalen Veterans Affairs Medical Center, Salt Lake City, Utah
| | - Matthew J Rossman
- Geriatric Research, Education, and Clinical Center, George E. Whalen Veterans Affairs Medical Center, Salt Lake City, Utah
- Department of Exercise and Sport Science, University of Utah, Salt Lake City, Utah
| | - Ryan M Broxterman
- Department of Medicine, Division of Geriatrics, University of Utah, Salt Lake City, Utah
- Geriatric Research, Education, and Clinical Center, George E. Whalen Veterans Affairs Medical Center, Salt Lake City, Utah
| | - Yann Le Fur
- Centre de Résonance Magnétique Biologique et Médicale, Aix-Marseille Universite, Centre National de la Recherche Scientifique, Marseille, France; and
| | - Eun-Kee Jeong
- Department of Radiology and Utah Center for Advanced Imaging Research, University of Utah, Salt Lake City, Utah
| | - Russell S Richardson
- Department of Medicine, Division of Geriatrics, University of Utah, Salt Lake City, Utah
- Geriatric Research, Education, and Clinical Center, George E. Whalen Veterans Affairs Medical Center, Salt Lake City, Utah
- Department of Nutrition and Integrative Physiology, University of Utah, Salt Lake City, Utah
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29
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McCrudden MC, Keir DA, Belfry GR. The effects of short work vs. longer work periods within intermittent exercise on V̇o 2p kinetics, muscle deoxygenation, and energy system contribution. J Appl Physiol (1985) 2017; 122:1435-1444. [PMID: 28336535 DOI: 10.1152/japplphysiol.00514.2016] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2016] [Revised: 02/21/2017] [Accepted: 03/16/2017] [Indexed: 11/22/2022] Open
Abstract
We examined the effects of inserting 3-s recovery periods during high-intensity cycling exercise at 25-s and 10-s intervals on pulmonary oxygen uptake (V̇o2p), muscle deoxygenation [deoxyhemoglobin (HHb)], their associated kinetics (τ), and energy system contributions. Eleven men (24 ± 3 yr) completed two trials of three cycling protocols: an 8-min continuous protocol (CONT) and two 8-min intermittent exercise protocols with work-to-rest periods of 25 s to 3 s (25INT) and 10 s to 3 s (10INT). Each protocol began with a step-transition from a 20-W baseline to a power output (PO) of 60% between lactate threshold and maximal V̇o2p (Δ60). This PO was maintained for 8 min in CONT, whereas 3-s periods of 20-W cycling were inserted every 10 s and 25 s after the transition to Δ60 in 10INT and 25INT, respectively. Breath-by-breath gas exchange measured by mass spectrometry and turbine and vastus lateralis [HHb] measured by near-infrared spectroscopy were recorded throughout. Arterialized-capillary lactate concentration ([Lac-]) was obtained before and 2 min postexercise. The τV̇o2p was lowest (P < 0.05) for 10INT (24 ± 4 s) and 25INT (23 ± 5 s) compared with CONT (28 ± 4 s), whereas HHb kinetics did not differ (P > 0.05) between conditions. Postexercise [Lac-] was lowest (P < 0.05) for 10INT (7.0 ± 1.7 mM), was higher for 25INT (10.3 ± 1.9 mM), and was greatest in CONT (14.3 ± 3.1 mM). Inserting 3-s recovery periods during heavy-intensity exercise speeded V̇o2p kinetics and reduced overall V̇o2p, suggesting an increased reliance on PCr-derived phosphorylation during the work period of INT compared with an identical PO performed continuously.NEW & NOTEWORTHY We report novel observations on the effects of differing heavy-intensity work durations between 3-s recovery periods on pulmonary oxygen uptake (V̇o2p) kinetics, muscle deoxygenation, and energy system contributions. Relative to continuous exercise, V̇o2p kinetics are faster in intermittent exercise, and increased frequency of 3-s recovery periods improves microvascular O2 delivery and reduces V̇o2p and arterialized-capillary lactate concentration. The metabolic burden of identical intensity work is altered when performed intermittently vs. continuously.
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Affiliation(s)
- Michael C McCrudden
- School of Kinesiology, Canadian Center for Activity and Aging, University of Western Ontario, London, Ontario, Canada
| | - Daniel A Keir
- School of Kinesiology, Canadian Center for Activity and Aging, University of Western Ontario, London, Ontario, Canada
| | - Glen R Belfry
- School of Kinesiology, Canadian Center for Activity and Aging, University of Western Ontario, London, Ontario, Canada
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McDonagh STJ, Vanhatalo A, Fulford J, Wylie LJ, Bailey SJ, Jones AM. Dietary nitrate supplementation attenuates the reduction in exercise tolerance following blood donation. Am J Physiol Heart Circ Physiol 2016; 311:H1520-H1529. [DOI: 10.1152/ajpheart.00451.2016] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/24/2016] [Accepted: 09/26/2016] [Indexed: 02/02/2023]
Abstract
We tested the hypothesis that dietary nitrate (NO3−)-rich beetroot juice (BR) supplementation could partially offset deteriorations in O2transport and utilization and exercise tolerance after blood donation. Twenty-two healthy volunteers performed moderate-intensity and ramp incremental cycle exercise tests prior to and following withdrawal of ∼450 ml of whole blood. Before donation, all subjects consumed seven 70-ml shots of NO3−-depleted BR [placebo (PL)] in the 48 h preceding the exercise tests. During the 48 h after blood donation, subjects consumed seven shots of BR (each containing 6.2 mmol of NO3−, n = 11) or PL ( n = 11) before repeating the exercise tests. Hemoglobin concentration and hematocrit were reduced by ∼8–9% following blood donation ( P < 0.05), with no difference between the BR and PL groups. Steady-state O2uptake during moderate-intensity exercise was ∼4% lower after than before donation in the BR group ( P < 0.05) but was unchanged in the PL group. The ramp test peak power decreased from predonation (341 ± 70 and 331 ± 68 W in PL and BR, respectively) to postdonation (324 ± 69 and 322 ± 66 W in PL and BR, respectively) in both groups ( P < 0.05). However, the decrement in performance was significantly less in the BR than PL group (2.7% vs. 5.0%, P < 0.05). NO3−supplementation reduced the O2cost of moderate-intensity exercise and attenuated the decline in ramp incremental exercise performance following blood donation. These results have implications for improving functional capacity following blood loss.
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Affiliation(s)
- Sinead T. J. McDonagh
- Sport and Health Sciences, College of Life and Environmental Sciences, St. Luke's Campus, University of Exeter, Exeter, United Kingdom; and
| | - Anni Vanhatalo
- Sport and Health Sciences, College of Life and Environmental Sciences, St. Luke's Campus, University of Exeter, Exeter, United Kingdom; and
| | - Jonathan Fulford
- University of Exeter Medical School, St. Luke's Campus, University of Exeter, Exeter, United Kingdom
| | - Lee J. Wylie
- Sport and Health Sciences, College of Life and Environmental Sciences, St. Luke's Campus, University of Exeter, Exeter, United Kingdom; and
| | - Stephen J. Bailey
- Sport and Health Sciences, College of Life and Environmental Sciences, St. Luke's Campus, University of Exeter, Exeter, United Kingdom; and
| | - Andrew M. Jones
- Sport and Health Sciences, College of Life and Environmental Sciences, St. Luke's Campus, University of Exeter, Exeter, United Kingdom; and
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31
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Niemeijer VM, Spee RF, Schoots T, Wijn PFF, Kemps HMC. Limitations of skeletal muscle oxygen delivery and utilization during moderate-intensity exercise in moderately impaired patients with chronic heart failure. Am J Physiol Heart Circ Physiol 2016; 311:H1530-H1539. [DOI: 10.1152/ajpheart.00474.2016] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/05/2016] [Accepted: 09/28/2016] [Indexed: 11/22/2022]
Abstract
The extent and speed of transient skeletal muscle deoxygenation during exercise onset in patients with chronic heart failure (CHF) are related to impairments of local O2 delivery and utilization. This study examined the physiological background of submaximal exercise performance in 19 moderately impaired patients with CHF (Weber class A, B, and C) compared with 19 matched healthy control (HC) subjects by measuring skeletal muscle oxygenation (SmO2) changes during cycling exercise. All subjects performed two subsequent moderate-intensity 6-min exercise tests (bouts 1 and 2) with measurements of pulmonary oxygen uptake kinetics and SmO2 using near-infrared spatially resolved spectroscopy at the vastus lateralis for determination of absolute oxygenation values, amplitudes, kinetics (mean response time for onset), and deoxygenation overshoot characteristics. In CHF, deoxygenation kinetics were slower compared with HC (21.3 ± 5.3 s vs. 16.7 ± 4.4 s, P < 0.05, respectively). After priming exercise (i.e., during bout 2), deoxygenation kinetics were accelerated in CHF to values no longer different from HC (16.9 ± 4.6 s vs. 15.4 ± 4.2 s, P = 0.35). However, priming did not speed deoxygenation kinetics in CHF subjects with a deoxygenation overshoot, whereas it did reduce the incidence of the overshoot in this specific group ( P < 0.05). These results provide evidence for heterogeneity with respect to limitations of O2 delivery and utilization during moderate-intensity exercise in patients with CHF, with slowed deoxygenation kinetics indicating a predominant O2 utilization impairment and the presence of a deoxygenation overshoot, with a reduction after priming in a subgroup, indicating an initial O2 delivery to utilization mismatch.
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Affiliation(s)
- Victor M. Niemeijer
- Department of Cardiology, Máxima Medical Centre, Veldhoven, the Netherlands
- Department of Applied Physics, Eindhoven University of Technology, Eindhoven, the Netherlands; and
| | - Ruud F. Spee
- Department of Cardiology, Máxima Medical Centre, Veldhoven, the Netherlands
| | - Thijs Schoots
- Department of Cardiology, Máxima Medical Centre, Veldhoven, the Netherlands
| | - Pieter F. F. Wijn
- Department of Applied Physics, Eindhoven University of Technology, Eindhoven, the Netherlands; and
- Department of Medical Physics, Máxima Medical Centre, Veldhoven, the Netherlands
| | - Hareld M. C. Kemps
- Department of Cardiology, Máxima Medical Centre, Veldhoven, the Netherlands
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Caldwell JT, Wardlow GC, Branch PA, Ramos M, Black CD, Ade CJ. Effect of exercise-induced muscle damage on vascular function and skeletal muscle microvascular deoxygenation. Physiol Rep 2016; 4:4/22/e13032. [PMID: 27884955 PMCID: PMC5358004 DOI: 10.14814/phy2.13032] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2016] [Accepted: 10/20/2016] [Indexed: 11/24/2022] Open
Abstract
This paper investigated the effects of unaccustomed eccentric exercise‐induced muscle damage (EIMD) on macro‐ and microvascular function. We tested the hypotheses that resting local and systemic endothelial‐dependent flow‐mediated dilation (FMD) and microvascular reactivity would decrease, V˙O2max would be altered, and that during ramp exercise, peripheral O2 extraction, evaluated via near‐infrared‐derived spectroscopy (NIRS) derived deoxygenated hemoglobin + myoglobin ([HHb]), would be distorted following EIMD. In 13 participants, measurements were performed prior to (Pre) and 48 h after a bout of knee extensor eccentric exercise designed to elicit localized muscle damage (Post). Flow‐mediated dilation and postocclusive reactive hyperemic responses measured in the superficial femoral artery served as a measurement of local vascular function relative to the damaged tissue, while the brachial artery served as an index of nonlocal, systemic, vascular function. During ramp‐incremental exercise on a cycle ergometer, [HHb] and tissue saturation (TSI%) in the m. vastus lateralis were measured. Superficial femoral artery FMD significantly decreased following EIMD (pre 6.75 ± 3.89%; post 4.01 ± 2.90%; P < 0.05), while brachial artery FMD showed no change. The [HHb] and TSI% amplitudes were not different following EIMD ([HHb]: pre, 16.9 ± 4.7; post 17.7 ± 4.9; TSI%: pre, 71.0 ± 19.7; post 71.0 ± 19.7; all P > 0.05). At each progressive increase in workload (i.e., 0–100% peak), the [HHb] and TOI% responses were similar pre‐ and 48 h post‐EIMD (P > 0.05). Additionally, V˙O2max was similar at pre‐ (3.0 ± 0.67 L min−1) to 48 h post (2.96 ± 0.60 L min−1)‐EIMD (P > 0.05). Results suggest that moderate eccentric muscle damage leads to impaired local, but not systemic, macrovascular dysfunction.
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Affiliation(s)
- Jacob T Caldwell
- Department of Kinesiology, Kansas State University, Manhattan, Kansas .,Department of Health and Exercise Science, the University of Oklahoma, Norman, Oklahoma
| | - Garrett C Wardlow
- Department of Health and Exercise Science, the University of Oklahoma, Norman, Oklahoma
| | - Patrece A Branch
- Department of Health and Exercise Science, the University of Oklahoma, Norman, Oklahoma
| | - Macarena Ramos
- Department of Health and Exercise Science, the University of Oklahoma, Norman, Oklahoma
| | - Christopher D Black
- Department of Health and Exercise Science, the University of Oklahoma, Norman, Oklahoma
| | - Carl J Ade
- Department of Kinesiology, Kansas State University, Manhattan, Kansas
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Nakajima T, Yasuda T, Koide S, Yamasoba T, Obi S, Toyoda S, Sato Y, Inoue T, Kano Y. Repetitive restriction of muscle blood flow enhances mTOR signaling pathways in a rat model. Heart Vessels 2016; 31:1685-95. [PMID: 26833042 DOI: 10.1007/s00380-016-0801-6] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/20/2015] [Accepted: 01/15/2016] [Indexed: 10/22/2022]
Abstract
Skeletal muscle is a plastic organ that adapts its mass to various stresses by affecting pathways that regulate protein synthesis and degradation. This study investigated the effects of repetitive restriction of muscle blood flow (RRMBF) on microvascular oxygen pressure (PmvO2), mammalian target of rapamycin (mTOR) signaling pathways, and transcripts associated with proteolysis in rat skeletal muscle. Eleven-week-old male Wistar rats under anesthesia underwent six RRMBF consisting of an external compressive force of 100 mmHg for 5 min applied to the proximal portion of the right thigh, each followed by 3 min rest. During RRMBF, PmvO2 was measured by phosphorescence quenching techniques. The total RNA and protein of the tibialis anterior muscle were obtained from control rats, and rats treated with RRMBF 0-6 h after the stimuli. The protein expression and phosphorylation of various signaling proteins were determined by western blotting. The mRNA expression level was measured by real-time RT-PCR analysis. The total muscle weight increased in rats 0 h after RRMBF, but not in rats 1-6 h. During RRMBF, PmvO2 significantly decreased (36.1 ± 5.7 to 5.9 ± 1.7 torr), and recovered at rest period. RRMBF significantly increased phosphorylation of p70 S6-kinase (p70S6k), a downstream target of mTOR, and ribosomal protein S6 1 h after the stimuli. The protein level of REDD1 and phosphorylation of AMPK and MAPKs did not change. The mRNA expression levels of FOXO3a, MuRF-1, and myostatin were not significantly altered. These results suggested that RRMBF significantly decreased PmvO2, and enhanced mTOR signaling pathways in skeletal muscle using a rat model, which may play a role in diminishing muscle atrophy under various conditions in human studies.
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Affiliation(s)
- Toshiaki Nakajima
- Department of Cardiovascular Medicine, Dokkyo Medical University and Heart Center, Dokkyo Medical University Hospital, 880 Kitakobayashi, Mibu, Tochigi, 321-0293, Japan.
| | | | - Seiichiro Koide
- Department of Engineering Science, Bioscience and Technology Program, University of Electro-Communications, Tokyo, Japan
| | | | - Syotaro Obi
- Department of Cardiovascular Medicine and Research Support Center, Dokkyo Medical Univerasity, Tochigi, Japan
| | - Shigeru Toyoda
- Department of Cardiovascular Medicine, Dokkyo Medical University and Heart Center, Dokkyo Medical University Hospital, 880 Kitakobayashi, Mibu, Tochigi, 321-0293, Japan
| | - Yoshiaki Sato
- Department of Basic Sciences in Medicine, Kaatsu International University, Battaramulla, Sri Lanka
| | - Teruo Inoue
- Department of Cardiovascular Medicine, Dokkyo Medical University and Heart Center, Dokkyo Medical University Hospital, 880 Kitakobayashi, Mibu, Tochigi, 321-0293, Japan
| | - Yutaka Kano
- Department of Engineering Science, Bioscience and Technology Program, University of Electro-Communications, Tokyo, Japan
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Ederer AK, Didier KD, Reiter LK, Brown M, Hardy R, Caldwell J, Black CD, Larson RD, Ade CJ. Influence of Adjuvant Therapy in Cancer Survivors on Endothelial Function and Skeletal Muscle Deoxygenation. PLoS One 2016; 11:e0147691. [PMID: 26807572 PMCID: PMC4726690 DOI: 10.1371/journal.pone.0147691] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2015] [Accepted: 01/07/2016] [Indexed: 12/16/2022] Open
Abstract
The cardiotoxic effects of adjuvant cancer treatments (i.e., chemotherapy and radiation treatment) have been well documented, but the effects on peripheral cardiovascular function are still unclear. We hypothesized that cancer survivors i) would have decreased resting endothelial function; and ii) altered muscle deoxygenation response during moderate intensity cycling exercise compared to cancer-free controls. A total of 8 cancer survivors (~70 months post-treatment) and 9 healthy controls completed a brachial artery FMD test, an index of endothelial-dependent dilation, followed by an incremental exercise test up to the ventilatory threshold (VT) on a cycle ergometer during which pulmonary V˙O2 and changes in near-infrared spectroscopy (NIRS)-derived microvascular tissue oxygenation (TOI), total hemoglobin concentration ([Hb]total), and muscle deoxygenation ([HHb] ≈ fractional O2 extraction) were measured. There were no significant differences in age, height, weight, and resting blood pressure between cancer survivors and control participants. Brachial artery FMD was similar between groups (P = 0.98). During exercise at the VT, TOI was similar between groups, but [Hb]total and [HHb] were significantly decreased in cancer survivors compared to controls (P < 0.01) The rate of change for TOI (ΔTOIΔ/V˙O2) and [HHb] (Δ[HHb]/ΔV˙O2) relative to ΔV˙O2 were decreased in cancer survivors compared to controls (P = 0.02 and P = 0.03 respectively). In cancer survivors, a decreased skeletal muscle microvascular function was observed during moderate intensity cycling exercise. These data suggest that adjuvant cancer therapies have an effect on the integrated relationship between O2 extraction, V˙O2 and O2 delivery during exercise.
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Affiliation(s)
- Austin K. Ederer
- Department of Health and Exercise Science, The University of Oklahoma, Norman, OK, United States of America
| | - Kaylin D. Didier
- Department of Health and Exercise Science, The University of Oklahoma, Norman, OK, United States of America
| | - Landon K. Reiter
- Department of Health and Exercise Science, The University of Oklahoma, Norman, OK, United States of America
| | - Michael Brown
- Department of Health and Exercise Science, The University of Oklahoma, Norman, OK, United States of America
| | - Rachel Hardy
- Department of Health and Exercise Science, The University of Oklahoma, Norman, OK, United States of America
| | - Jacob Caldwell
- Department of Health and Exercise Science, The University of Oklahoma, Norman, OK, United States of America
| | - Christopher D. Black
- Department of Health and Exercise Science, The University of Oklahoma, Norman, OK, United States of America
| | - Rebecca D. Larson
- Department of Health and Exercise Science, The University of Oklahoma, Norman, OK, United States of America
| | - Carl J. Ade
- Department of Health and Exercise Science, The University of Oklahoma, Norman, OK, United States of America
- * E-mail:
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Okushima D, Poole DC, Rossiter HB, Barstow TJ, Kondo N, Ohmae E, Koga S. Muscle deoxygenation in the quadriceps during ramp incremental cycling: Deep vs. superficial heterogeneity. J Appl Physiol (1985) 2015; 119:1313-9. [PMID: 26404619 DOI: 10.1152/japplphysiol.00574.2015] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2015] [Accepted: 09/21/2015] [Indexed: 01/31/2023] Open
Abstract
Muscle deoxygenation (i.e., deoxy[Hb + Mb]) during exercise assesses the matching of oxygen delivery (Q̇O2) to oxygen utilization (V̇O2). Until now limitations in near-infrared spectroscopy (NIRS) technology did not permit discrimination of deoxy[Hb + Mb] between superficial and deep muscles. In humans, the deep quadriceps is more highly vascularized and oxidative than the superficial quadriceps. Using high-power time-resolved NIRS, we tested the hypothesis that deoxygenation of the deep quadriceps would be less than in superficial muscle during incremental cycling exercise in eight males. Pulmonary V̇O2 was measured and muscle deoxy[Hb + Mb] was determined in the superficial vastus lateralis (VL), vastus medialis (VM), and rectus femoris (RF-s) and the deep rectus femoris (RF-d). deoxy[Hb + Mb] in RF-d was significantly less than VL at 70% (67.2 ± 7.0 vs. 75.5 ± 10.7 μM) and 80% (71.4 ± 11.0 vs. 79.0 ± 15.4 μM) of peak work rate (WR(peak)), but greater than VL and VM at WR(peak) (87.7 ± 32.5 vs. 76.6 ± 17.5 and 75.1 ± 19.9 μM). RF-s was intermediate at WR(peak) (82.6 ± 18.7 μM). Total hemoglobin and myoglobin concentration and tissue oxygen saturation were significantly greater in RF-d than RF-s throughout exercise. The slope of deoxy[Hb + Mb] increase (proportional to Q̇O2/V̇O2) in VL and VM slowed markedly above 70% WR(peak), whereas it became greater in RF-d. This divergent deoxygenation pattern may be due to a greater population of slow-twitch muscle fibers in the RF-d muscle and the differential recruitment profiles and vascular and metabolic control properties of specific fiber populations within superficial and deeper muscle regions.
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Affiliation(s)
- Dai Okushima
- Applied Physiology Laboratory, Kobe Design University, Kobe, Hyogo, Japan
| | - David C Poole
- Departments of Kinesiology and Anatomy and Physiology, Kansas State University, Manhattan, Kansas
| | - Harry B Rossiter
- Rehabilitation Clinical Trials Center, Division of Respiratory & Critical Care Physiology & Medicine, Los Angeles Biomedical Research Institute at Harbor-University of California Los Angeles Medical Center, Torrance, California
| | - Thomas J Barstow
- Departments of Kinesiology and Anatomy and Physiology, Kansas State University, Manhattan, Kansas
| | | | | | - Shunsaku Koga
- Applied Physiology Laboratory, Kobe Design University, Kobe, Hyogo, Japan;
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Schlup SJ, Ade CJ, Broxterman RM, Barstow TJ. Discrepancy between femoral and capillary blood flow kinetics during knee extension exercise. Respir Physiol Neurobiol 2015; 219:69-77. [PMID: 26304841 DOI: 10.1016/j.resp.2015.08.005] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2015] [Revised: 08/14/2015] [Accepted: 08/17/2015] [Indexed: 11/29/2022]
Abstract
Capillary blood flow (QCAP) kinetics have previously been shown to be significantly slower than femoral artery (QFA) kinetics following the onset of dynamic knee extension exercise. If the increase in QCAP does not follow a similar time course to QFA, then a substantial proportion of the available blood flow is not distributed to the working muscle. One possible explanation for this discrepancy is that blood flow also increases to the nonworking lower leg muscles. Therefore, the present study aimed to determine if a reduction in lower limb blood flow, via arterial occlusion below the knee, alters the kinetics of QFA and QCAP during knee extension exercise, and thus provide insight into the potential mechanisms controlling the rapid increase in QFA. Subjects performed a ramp max test to determine the work rate at which gas exchange threshold (GET) occurred. At least four constant work rate trials with and without below-knee occlusion were conducted at work rates eliciting ∼ 80% GET. Pulmonary gas exchange, near-infrared spectroscopy and QFA measurements were taken continuously during each exercise bout. Muscle oxygen uptake (VO2m) and deoxy[hemoglobin+myoglobin] were used to estimate QCAP. There was no significant difference between the uncuffed and cuffed conditions in any response (P>0.05). The mean response times (MRT) of QFA were 18.7 ± 14.2s (uncuffed) and 24.6 ± 14.9s (cuffed). QCAP MRTs were 51.8 ± 23.4s (uncuffed) and 56.7 ± 23.2s (cuffed), which were not significantly different from the time constants (τ) of VO2m (39.7 ± 23.2s (uncuffed) and 46.3 ± 24.1s (cuffed). However, the MRT of QFA was significantly faster (P<0.05) than the MRT of QCAP and τVO2m. τVO2m and MRT QCAP were significantly correlated and estimated QCAP kinetics tracked VO2m following exercise onset. Cuffing below the knee did not significantly change the kinetics of QFA, QCAP or VO2m, although an effect size of 1.02 suggested that a significant effect on QFA may have been hidden by small subject number.
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Affiliation(s)
- S J Schlup
- Department of Kinesiology, Kansas State University, Manhattan, KS, USA
| | - C J Ade
- Department of Health and Exercise Science, Oklahoma University, Norman, OK, USA
| | - R M Broxterman
- Department of Kinesiology, Kansas State University, Manhattan, KS, USA; Department of Anatomy and Physiology, Kansas State University, Manhattan, KS, USA
| | - T J Barstow
- Department of Kinesiology, Kansas State University, Manhattan, KS, USA.
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Niemeijer VM, Spee RF, Jansen JP, Buskermolen ABC, van Dijk T, Wijn PFF, Kemps HMC. Test-retest reliability of skeletal muscle oxygenation measurements during submaximal cycling exercise in patients with chronic heart failure. Clin Physiol Funct Imaging 2015; 37:68-78. [DOI: 10.1111/cpf.12269] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2015] [Accepted: 04/27/2015] [Indexed: 01/26/2023]
Affiliation(s)
| | - Ruud F. Spee
- Department of Cardiology; Máxima Medical Centre; Veldhoven The Netherlands
| | - Jasper P. Jansen
- Department of Biomedical Engineering; Eindhoven University of Technology; Eindhoven The Netherlands
| | | | - Thomas van Dijk
- Department of Medical Physics; Máxima Medical Centre; Veldhoven The Netherlands
| | - Pieter F. F. Wijn
- Department of Applied Physics; Eindhoven University of Technology; Eindhoven The Netherlands
- Department of Medical Physics; Máxima Medical Centre; Veldhoven The Netherlands
| | - Hareld M. C. Kemps
- Department of Cardiology; Máxima Medical Centre; Veldhoven The Netherlands
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Fukuoka Y, Poole DC, Barstow TJ, Kondo N, Nishiwaki M, Okushima D, Koga S. Reduction of V̇O2 slow component by priming exercise: novel mechanistic insights from time-resolved near-infrared spectroscopy. Physiol Rep 2015; 3:3/6/e12432. [PMID: 26109190 PMCID: PMC4510633 DOI: 10.14814/phy2.12432] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Novel time-resolved near-infrared spectroscopy (TR-NIRS), with adipose tissue thickness correction, was used to test the hypotheses that heavy priming exercise reduces the V̇O2 slow component (V̇O2SC) (1) by elevating microvascular [Hb] volume at multiple sites within the quadriceps femoris (2) rather than reducing the heterogeneity of muscle deoxygenation kinetics. Twelve subjects completed two 6-min bouts of heavy work rate exercise, separated by 6 min of unloaded cycling. Priming exercise induced faster overall V̇O2 kinetics consequent to a substantial reduction in the V̇O2SC (0.27 ± 0.12 vs. 0.11 ± 0.09 L·min−1, P < 0.05) with an unchanged primary V̇O2 time constant. An increased baseline for the primed bout [total (Hb + Mb)] (197.5 ± 21.6 vs. 210.7 ± 22.5 μmol L−1, P < 0.01), reflecting increased microvascular [Hb] volume, correlated significantly with the V̇O2SC reduction. At multiple sites within the quadriceps femoris, priming exercise reduced the baseline and slowed the increase in [deoxy (Hb + Mb)]. Changes in the intersite coefficient of variation in the time delay and time constant of [deoxy (Hb + Mb)] during the second bout were not correlated with the V̇O2SC reduction. These results support a mechanistic link between priming exercise-induced increase in muscle [Hb] volume and the reduced V̇O2SC that serves to speed overall V̇O2 kinetics. However, reduction in the heterogeneity of muscle deoxygenation kinetics does not appear to be an obligatory feature of the priming response.
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Affiliation(s)
- Yoshiyuki Fukuoka
- Environmental Physiology Laboratory, Prefectural University of Kumamoto, Kumamoto, Japan Graduate School of Health and Sports Science, Doshisha University, Kyoto, Japan
| | - David C Poole
- Departments of Anatomy and Physiology and Kinesiology, Kansas State University, Manhattan, Kansas
| | - Thomas J Barstow
- Departments of Anatomy and Physiology and Kinesiology, Kansas State University, Manhattan, Kansas
| | - Narihiko Kondo
- Graduate School of Cultural Studies and Human Science, Kobe University, Kobe, Japan
| | - Masato Nishiwaki
- Faculty of Engineering, Osaka Institute of Technology, Osaka, Japan
| | - Dai Okushima
- Applied Physiology Laboratory, Kobe Design University, Kobe, Japan
| | - Shunsaku Koga
- Applied Physiology Laboratory, Kobe Design University, Kobe, Japan
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39
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Buck AKW, Elder CP, Donahue MJ, Damon BM. Matching of postcontraction perfusion to oxygen consumption across submaximal contraction intensities in exercising humans. J Appl Physiol (1985) 2015; 119:280-9. [PMID: 26066829 DOI: 10.1152/japplphysiol.01027.2014] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2014] [Accepted: 06/08/2015] [Indexed: 12/23/2022] Open
Abstract
Studying the magnitude and kinetics of blood flow, oxygen extraction, and oxygen consumption at exercise onset and during the recovery from exercise can lead to insights into both the normal control of metabolism and blood flow and the disturbances to these processes in metabolic and cardiovascular diseases. The purpose of this study was to examine the on- and off-kinetics for oxygen delivery, extraction, and consumption as functions of submaximal contraction intensity. Eight healthy subjects performed four 1-min isometric dorsiflexion contractions, with two at 20% MVC and two at 40% MVC. During one contraction at each intensity, relative perfusion changes were measured by using arterial spin labeling, and the deoxyhemoglobin percentage (%HHb) was estimated using the spin- and gradient-echo sequence and a previously published empirical calibration. For the whole group, the mean perfusion did not increase during contraction. The %HHb increased from ∼28 to 38% during contractions of each intensity, with kinetics well described by an exponential function and mean response times (MRTs) of 22.7 and 21.6 s for 20 and 40% MVC, respectively. Following contraction, perfusion increased ∼2.5-fold. The %HHb, oxygen consumption, and perfusion returned to precontraction levels with MRTs of 27.5, 46.4, and 50.0 s, respectively (20% MVC), and 29.2, 75.3, and 86.0 s, respectively (40% MVC). These data demonstrate in human subjects the varied recovery rates of perfusion and oxygen consumption, along with the similar rates of %HHb recovery, across these exercise intensities.
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Affiliation(s)
- Amanda K W Buck
- Vanderbilt University Institute of Imaging Science, Vanderbilt University, Nashville, Tennessee; Department of Radiology and Radiological Sciences, Vanderbilt University, Nashville, Tennessee; Department of Biomedical Engineering, Vanderbilt University, Nashville, Tennessee
| | - Christopher P Elder
- Vanderbilt University Institute of Imaging Science, Vanderbilt University, Nashville, Tennessee
| | - Manus J Donahue
- Vanderbilt University Institute of Imaging Science, Vanderbilt University, Nashville, Tennessee; Department of Radiology and Radiological Sciences, Vanderbilt University, Nashville, Tennessee; Department of Psychiatry, Vanderbilt University, Nashville, Tennessee; Department of Neurology, Vanderbilt University, Nashville, Tennessee; Department of Physics and Astronomy, Vanderbilt University, Nashville, Tennessee; and
| | - Bruce M Damon
- Vanderbilt University Institute of Imaging Science, Vanderbilt University, Nashville, Tennessee; Department of Radiology and Radiological Sciences, Vanderbilt University, Nashville, Tennessee; Department of Biomedical Engineering, Vanderbilt University, Nashville, Tennessee; Department of Molecular Physiology and Biophysics Vanderbilt University, Nashville, Tennessee
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Koga S, Barstow TJ, Okushima D, Rossiter HB, Kondo N, Ohmae E, Poole DC. Validation of a high-power, time-resolved, near-infrared spectroscopy system for measurement of superficial and deep muscle deoxygenation during exercise. J Appl Physiol (1985) 2015; 118:1435-42. [PMID: 25840439 DOI: 10.1152/japplphysiol.01003.2014] [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: 11/10/2014] [Accepted: 03/31/2015] [Indexed: 11/22/2022] Open
Abstract
Near-infrared assessment of skeletal muscle is restricted to superficial tissues due to power limitations of spectroscopic systems. We reasoned that understanding of muscle deoxygenation may be improved by simultaneously interrogating deeper tissues. To achieve this, we modified a high-power (∼8 mW), time-resolved, near-infrared spectroscopy system to increase depth penetration. Precision was first validated using a homogenous optical phantom over a range of inter-optode spacings (OS). Coefficients of variation from 10 measurements were minimal (0.5-1.9%) for absorption (μa), reduced scattering, simulated total hemoglobin, and simulated O2 saturation. Second, a dual-layer phantom was constructed to assess depth sensitivity, and the thickness of the superficial layer was varied. With a superficial layer thickness of 1, 2, 3, and 4 cm (μa = 0.149 cm(-1)), the proportional contribution of the deep layer (μa = 0.250 cm(-1)) to total μa was 80.1, 26.9, 3.7, and 0.0%, respectively (at 6-cm OS), validating penetration to ∼3 cm. Implementation of an additional superficial phantom to simulate adipose tissue further reduced depth sensitivity. Finally, superficial and deep muscle spectroscopy was performed in six participants during heavy-intensity cycle exercise. Compared with the superficial rectus femoris, peak deoxygenation of the deep rectus femoris (including the superficial intermedius in some) was not significantly different (deoxyhemoglobin and deoxymyoglobin concentration: 81.3 ± 20.8 vs. 78.3 ± 13.6 μM, P > 0.05), but deoxygenation kinetics were significantly slower (mean response time: 37 ± 10 vs. 65 ± 9 s, P ≤ 0.05). These data validate a high-power, time-resolved, near-infrared spectroscopy system with large OS for measuring the deoxygenation of deep tissues and reveal temporal and spatial disparities in muscle deoxygenation responses to exercise.
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Affiliation(s)
- Shunsaku Koga
- Applied Physiology Laboratory, Kobe Design University, Kobe, Japan;
| | - Thomas J Barstow
- Departments of Anatomy and Physiology and Kinesiology, Kansas State University, Manhattan, Kansas
| | - Dai Okushima
- Applied Physiology Laboratory, Kobe Design University, Kobe, Japan
| | - Harry B Rossiter
- Rehabilitation Clinical Trials Center, Division of Respiratory & Critical Care Physiology & Medicine, Los Angeles Biomedical Research Institute at Harbor-UCLA Medical Center, Torrance, California
| | | | | | - David C Poole
- Departments of Anatomy and Physiology and Kinesiology, Kansas State University, Manhattan, Kansas
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Adami A, Koga S, Kondo N, Cannon DT, Kowalchuk JM, Amano T, Rossiter HB. Changes in whole tissue heme concentration dissociates muscle deoxygenation from muscle oxygen extraction during passive head-up tilt. J Appl Physiol (1985) 2015; 118:1091-9. [PMID: 25678700 DOI: 10.1152/japplphysiol.00918.2014] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2014] [Accepted: 02/06/2015] [Indexed: 11/22/2022] Open
Abstract
Skeletal muscle deoxygenated hemoglobin and myoglobin concentration ([HHb]), assessed by near-infrared spectroscopy (NIRS), is commonly used as a surrogate of regional O2 extraction (reflecting the O2 delivery-to-consumption ratio, Q̇/V̇o2). However, [HHb] change (Δ[HHb]) is also influenced by capillary-venous heme concentration, and/or small blood vessel volume (reflected in total heme; [THb]). We tested the hypotheses that Δ[HHb] is associated with O2 extraction, and insensitive to [THb], over a wide range of Q̇/V̇o2 elicited by passive head-up tilt (HUT; 10-min, 15° increments, between -10° and 75°). Steady-state common femoral artery blood flow (FBF) was measured by echo-Doppler, and time-resolved NIRS measured [HHb] and [THb] of vastus lateralis (VL) and gastrocnemius (GS) in 13 men. EMG confirmed muscles were inactive. During HUT in VL [HHb] increased linearly (57 ± 10 to 101 ± 16 μM; P < 0.05 above 15°) and was associated (r(2) ∼ 0.80) with the reduction in FBF (618 ± 75 ml/min at 0° to 268 ± 52 ml/min at 75°; P < 0.05 above 30°) and the increase in [THb] (228 ± 30 vs. 252 ± 32 μM; P < 0.05 above 15°). GS response was qualitatively similar to VL. However, there was wide variation within and among individuals, such that the overall limits of agreement between Δ[HHb] and ΔFBF ranged from -35 to +19% across both muscles. Neither knowledge of tissue O2 saturation nor vascular compliance could appropriately account for the Δ[HHb]-ΔFBF dissociation. Thus, under passive tilt, [HHb] is influenced by Q̇/V̇o2, as well as microvascular hematocrit and/or tissue blood vessel volume, complicating its use as a noninvasive surrogate for muscle microvascular O2 extraction.
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Affiliation(s)
- Alessandra Adami
- Rehabilitation Clinical Trials Center, Division of Respiratory and Critical Care Physiology and Medicine, Los Angeles Biomedical Research Institute at Harbor-UCLA Medical Center, Torrance, California
| | - Shunsaku Koga
- Applied Physiology Laboratory, Kobe Design University, Kobe, Japan
| | - Narihiko Kondo
- Laboratory for Applied Human Physiology, Graduate School of Human Development and Environment, Kobe University, Kobe, Japan; and
| | - Daniel T Cannon
- Rehabilitation Clinical Trials Center, Division of Respiratory and Critical Care Physiology and Medicine, Los Angeles Biomedical Research Institute at Harbor-UCLA Medical Center, Torrance, California
| | - John M Kowalchuk
- School of Kinesiology and Department of Physiology and Pharmacology, The University of Western Ontario, London, Ontario, Canada
| | - Tatsuro Amano
- Laboratory for Applied Human Physiology, Graduate School of Human Development and Environment, Kobe University, Kobe, Japan; and
| | - Harry B Rossiter
- Rehabilitation Clinical Trials Center, Division of Respiratory and Critical Care Physiology and Medicine, Los Angeles Biomedical Research Institute at Harbor-UCLA Medical Center, Torrance, California;
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SAYNOR ZOELOUISE, BARKER ALANROBERT, OADES PATRICKJOHN, WILLIAMS CRAIGANTHONY. Impaired Aerobic Function in Patients with Cystic Fibrosis during Ramp Exercise. Med Sci Sports Exerc 2014; 46:2271-8. [DOI: 10.1249/mss.0000000000000369] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Koga S, Rossiter HB, Heinonen I, Musch TI, Poole DC. Dynamic heterogeneity of exercising muscle blood flow and O2 utilization. Med Sci Sports Exerc 2014; 46:860-76. [PMID: 24091989 DOI: 10.1249/mss.0000000000000178] [Citation(s) in RCA: 103] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Resolving the bases for different physiological functioning or exercise performance within a population is dependent on our understanding of control mechanisms. For example, when most young healthy individuals run or cycle at moderate intensities, oxygen uptake (VO2) kinetics are rapid and the amplitude of the VO2 response is not constrained by O2 delivery. For this to occur, muscle O2 delivery (i.e., blood flow × arterial O2 concentration) must be coordinated superbly with muscle O2 requirements (VO2), the efficacy of which may differ among muscles and distinct fiber types. When the O2 transport system succumbs to the predations of aging or disease (emphysema, heart failure, and type 2 diabetes), muscle O2 delivery and O2 delivery-VO2 matching and, therefore, muscle contractile function become impaired. This forces greater influence of the upstream O2 transport pathway on muscle aerobic energy production, and the O2 delivery-VO2 relationship(s) assumes increased importance. This review is the first of its kind to bring a broad range of available techniques, mostly state of the art, including computer modeling, radiolabeled microspheres, positron emission tomography, magnetic resonance imaging, near-infrared spectroscopy, and phosphorescence quenching to resolve the O2 delivery-VO2 relationships and inherent heterogeneities at the whole body, interorgan, muscular, intramuscular, and microvascular/myocyte levels. Emphasis is placed on the following: 1) intact humans and animals as these provide the platform essential for framing and interpreting subsequent investigations, 2) contemporary findings using novel technological approaches to elucidate O2 delivery-VO2 heterogeneities in humans, and 3) future directions for investigating how normal physiological responses can be explained by O2 delivery-VO2 heterogeneities and the impact of aging/disease on these processes.
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Affiliation(s)
- Shunsaku Koga
- 1Applied Physiology Laboratory, Kobe Design University, JAPAN; 2Division of Respiratory and Critical Care Physiology and Medicine, Los Angeles Biomedical Research Institute at Harbor-UCLA Medical Center, and School of Biomedical Sciences, University of Leeds, Leeds, UNITED KINGDOM; 3Turku PET Centre and Research Centre of Applied and Preventive Cardiovascular Medicine, University of Turku and Turku University Hospital, Turku, FINLAND; Division of Experimental Cardiology, Thoraxcenter, Erasmus MC, University Medical Center Rotterdam, Rotterdam, THE NETHERLANDS; and 4Departments of Kinesiology and Anatomy and Physiology, Kansas State University, Manhattan, KS
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Effects of increased skin blood flow on muscle oxygenation/deoxygenation: comparison of time-resolved and continuous-wave near-infrared spectroscopy signals. Eur J Appl Physiol 2014; 115:335-43. [DOI: 10.1007/s00421-014-3019-2] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2014] [Accepted: 10/02/2014] [Indexed: 01/23/2023]
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Spencer MD, Amano T, Kondo N, Kowalchuk JM, Koga S. Muscle O2 extraction reserve during intense cycling is site-specific. J Appl Physiol (1985) 2014; 117:1199-206. [PMID: 25257877 DOI: 10.1152/japplphysiol.00060.2014] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The present study compared peak muscle deoxygenation ([HHb]peak) responses at three quadriceps sites during occlusion (OCC), ramp incremental (RI), severe- (SVR) and moderate-intensity (MOD) exercise. Seven healthy men (25 ± 4 yr) each completed a stationary cycling RI (20 W/min) test to determine [HHb]peak [at distal and proximal vastus lateralis (VLD and VLP) and rectus femoris (RF)], peak V̇O2 (V̇O(2peak)), gas exchange threshold (GET), and peak work rate (WR(peak)). Subjects also completed MOD (WR = 80% GET) and SVR exercise (WR corresponding to 120% V̇O(2peak)) with absolute [HHb] (quantified by multichannel, time-resolved near-infrared spectroscopy) and pulmonary VO2 (V̇O(2p)) monitored continuously. Additionally, [HHb] and total hemoglobin ([Hb]tot) were monitored at rest and during subsequent OCC (250 mmHg). Site-specific adipose tissue thickness was assessed (B-mode ultrasound), and its relationship with resting [Hb]tot was used to correct absolute [HHb]. For VLD and RF, [HHb]peak was higher (P < 0.05) during OCC (VLD = 111 ± 38, RF = 114 ± 26 μM) than RI (VLD 64 ± 14, RF = 85 ± 20) and SVR (VLD = 63 ± 13, RF = 81 ± 18). [HHb]peak was similar (P > 0.05) across these conditions at the VLP (OCC = 67 ± 17, RI = 69 ± 17, SVR = 63 ± 17 μM). [HHb] peaked and then decreased prior to exercise cessation during SVR at all three muscle sites. [HHb]peak during MOD was consistently lower than other conditions at all sites. A "[HHb] reserve" exists during intense cycling at the VLD and RF, likely implying either sufficient blood flow to meet oxidative demands or insufficient diffusion time for complete equilibration. In VLP this [HHb] reserve was absent, suggesting that a critical PO2 may be challenged during intense cycling.
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Affiliation(s)
- Matthew D Spencer
- Kobe Design University, Kobe, Hyogo, Japan; The University of Western Ontario, London, Ontario, Canada; and
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Bellotti C, Calabria E, Capelli C, Pogliaghi S. Determination of maximal lactate steady state in healthy adults: can NIRS help? Med Sci Sports Exerc 2014; 45:1208-16. [PMID: 23274611 DOI: 10.1249/mss.0b013e3182828ab2] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
PURPOSE We tested the hypothesis that the maximal lactate steady state (MLSS) can be accurately determined in healthy subjects based on measures of deoxygenated hemoglobin (deoxyHb), an index of oxygen extraction measured noninvasively by near-infrared spectroscopy (NIRS). METHODS Thirty-two healthy men (mean ± SD age = 48 ± 17 yr, range = 23-74 yr) performed an incremental cycling test to exhaustion and square wave tests for MLSS determination. Cardiorespiratory variables were measured bbb and deoxyHb was monitored noninvasively on the right vastus lateralis with a quantitative NIRS device. The individual values of V˙O2 and HR corresponding to the MLSS were calculated and compared to the NIRS-derived MLSS (NIRSMLSS) that was, in turn, determined by double linear function fitting of deoxyHb during the incremental exercise. RESULTS V˙O2 and HR at MLSS were 2.25 ± 0.54 L·min (76% ± 9% V˙O2max) and 133 ± 14 bpm (81% ± 7% HRmax), respectively. Muscle O2 extraction increased as a function of exercise intensity up to a deflection point, NIRSMLSS, at which V˙O2 and HR were 2.23 ± 0.59 L·min (76% ± 9% V˙O2max) and 136 ± 17 bpm (82% ± 8% HRmax), respectively. For both V˙O2 and HR, the difference of NIRSMLSS from MLSS values was not significant and the measures were highly correlated (r = 0.81 and r = 0.76). The Bland-Altman analysis confirmed a nonsignificant bias for V˙O2 and HR (-0.015 L·min and 3 bpm, respectively) and a small imprecision of 0.26 L·min and 8 bpm. CONCLUSIONS A plateau in muscle O2 extraction was demonstrated in coincidence with MLSS during an incremental cycling exercise, confirming the hypothesis that this functional parameter can be accurately estimated with a quantitative NIRS device. The main advantages of NIRSMLSS over lactate-based techniques are the noninvasiveness and the time/cost efficiency.
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Affiliation(s)
- Cecilia Bellotti
- Department of Neurological, Neuropsychological, Morphological and Exercise Sciences, School of Exercise and Sport Sciences, University of Verona, Italy
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Breese BC, McNarry MA, Marwood S, Blackwell JR, Bailey SJ, Jones AM. Beetroot juice supplementation speeds O2 uptake kinetics and improves exercise tolerance during severe-intensity exercise initiated from an elevated metabolic rate. Am J Physiol Regul Integr Comp Physiol 2013; 305:R1441-50. [PMID: 24089377 DOI: 10.1152/ajpregu.00295.2013] [Citation(s) in RCA: 111] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Recent research has suggested that dietary nitrate (NO3(-)) supplementation might alter the physiological responses to exercise via specific effects on type II muscle. Severe-intensity exercise initiated from an elevated metabolic rate would be expected to enhance the proportional activation of higher-order (type II) muscle fibers. The purpose of this study was, therefore, to test the hypothesis that, compared with placebo (PL), NO3(-)-rich beetroot juice (BR) supplementation would speed the phase II VO2 kinetics (τ(p)) and enhance exercise tolerance during severe-intensity exercise initiated from a baseline of moderate-intensity exercise. Nine healthy, physically active subjects were assigned in a randomized, double-blind, crossover design to receive BR (140 ml/day, containing ~8 mmol of NO3(-)) and PL (140 ml/day, containing ~0.003 mmol of NO3(-)) for 6 days. On days 4, 5, and 6 of the supplementation periods, subjects completed a double-step exercise protocol that included transitions from unloaded to moderate-intensity exercise (U→M) followed immediately by moderate to severe-intensity exercise (M→S). Compared with PL, BR elevated resting plasma nitrite concentration (PL: 65 ± 32 vs. BR: 348 ± 170 nM, P < 0.01) and reduced the VO2 τ(p) in M→S (PL: 46 ± 13 vs. BR: 36 ± 10 s, P < 0.05) but not U→M (PL: 25 ± 4 vs. BR: 27 ± 6 s, P > 0.05). During M→S exercise, the faster VO2 kinetics coincided with faster near-infrared spectroscopy-derived muscle [deoxyhemoglobin] kinetics (τ; PL: 20 ± 9 vs. BR: 10 ± 3 s, P < 0.05) and a 22% greater time-to-task failure (PL: 521 ± 158 vs. BR: 635 ± 258 s, P < 0.05). Dietary supplementation with NO3(-)-rich BR juice speeds VO2 kinetics and enhances exercise tolerance during severe-intensity exercise when initiated from an elevated metabolic rate.
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Affiliation(s)
- Brynmor C Breese
- Sport and Exercise Physiology Research Team, Liverpool Hope University, Liverpool, United Kingdom
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Barker AR, Trebilcock E, Breese B, Jones AM, Armstrong N. The effect of priming exercise on O2 uptake kinetics, muscle O2 delivery and utilization, muscle activity, and exercise tolerance in boys. Appl Physiol Nutr Metab 2013; 39:308-17. [PMID: 24552371 DOI: 10.1139/apnm-2013-0174] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
This study used priming exercise in young boys to investigate (i) how muscle oxygen delivery and oxygen utilization, and muscle activity modulate oxygen uptake kinetics during exercise; and (ii) whether the accelerated oxygen uptake kinetics following priming exercise can improve exercise tolerance. Seven boys that were aged 11.3 ± 1.6 years completed either a single bout (bout 1) or repeated bouts with 6 min of recovery (bout 2) of very heavy-intensity cycling exercise. During the tests oxygen uptake, muscle oxygenation, muscle electrical activity and exercise tolerance were measured. Priming exercise most likely shortened the oxygen uptake mean response time (change, ±90% confidence limits; -8.0 s, ±3.0), possibly increased the phase II oxygen uptake amplitude (0.11 L·min(-1), ±0.09) and very likely reduced the oxygen uptake slow component amplitude (-0.08 L·min(-1), ±0.07). Priming resulted in a likely reduction in integrated electromyography (-24% baseline, ±21% and -25% baseline, ±19) and a very likely reduction in Δ deoxyhaemoglobin/Δoxygen uptake (-0.16, ±0.11 and -0.09, ±0.05) over the phase II and slow component portions of the oxygen uptake response, respectively. A correlation was present between the change in tissue oxygenation index during bout 2 and the change in the phase II (r = -0.72, likely negative) and slow component (r = 0.72, likely positive) oxygen uptake amplitudes following priming exercise, but not for muscle activity. Exercise tolerance was likely reduced (change -177 s, ±180) following priming exercise. The altered phase II and slow component oxygen uptake amplitudes in boys following priming exercise are linked to an improved localised matching of muscle oxygen delivery to oxygen uptake and not muscle electrical activity. Despite more rapid oxygen uptake kinetics following priming exercise, exercise tolerance was not enhanced.
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Affiliation(s)
- Alan R Barker
- Children's Health and Exercise Research Centre, Sport and Health Sciences, University of Exeter, Exeter EX1 2LU, UK
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Bowen TS, Rossiter HB, Benson AP, Amano T, Kondo N, Kowalchuk JM, Koga S. Slowed oxygen uptake kinetics in hypoxia correlate with the transient peak and reduced spatial distribution of absolute skeletal muscle deoxygenation. Exp Physiol 2013; 98:1585-96. [DOI: 10.1113/expphysiol.2013.073270] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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50
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Estimated contribution of hemoglobin and myoglobin to near infrared spectroscopy. Respir Physiol Neurobiol 2013; 186:180-7. [DOI: 10.1016/j.resp.2013.01.012] [Citation(s) in RCA: 86] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2012] [Revised: 12/14/2012] [Accepted: 01/21/2013] [Indexed: 11/20/2022]
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