AJP - Regu Information on EB 2010
HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
QUICK SEARCH:   [advanced]


     

Am J Physiol Regul Integr Comp Physiol 284: R291-R303, 2003. First published October 3, 2002; doi:10.1152/ajpregu.00155.2002
0363-6119/03 $5.00
This Article
Right arrow Full Text
Right arrow Full Text (PDF)
Right arrow All Versions of this Article:
284/2/R291    most recent
00155.2002v1
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Right arrow Citation Map
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in Web of Science
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Web of Science (49)
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Calbet, J. A. L.
Right arrow Articles by Saltin, B.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Calbet, J. A. L.
Right arrow Articles by Saltin, B.
Vol. 284, Issue 2, R291-R303, February 2003

Determinants of maximal oxygen uptake in severe acute hypoxia

J. A. L. Calbet1,2, R. Boushel2,3, G. Rådegran2, H. Søndergaard2, P. D. Wagner4, and B. Saltin2

1 Department of Physical Education, University of Las Palmas de Gran Canaria, 35017 Las Palmas de Gran Canaria, Spain; 2 The Copenhagen Muscle Research Centre, Rigshospitalet, 2200 Copenhagen N, Denmark; 3 Department of Exercise Science, Concordia University, Montreal, Quebec, Canada H4B 1R6; and 4 Department of Medicine, Section of Physiology, University of California San Diego, La Jolla, California 92093

To unravel the mechanisms by which maximal oxygen uptake (VO2 max) is reduced with severe acute hypoxia in humans, nine Danish lowlanders performed incremental cycle ergometer exercise to exhaustion, while breathing room air (normoxia) or 10.5% O2 in N2 (hypoxia, ~5,300 m above sea level). With hypoxia, exercise PaO2 dropped to 31-34 mmHg and arterial O2 content (CaO2) was reduced by 35% (P < 0.001). Forty-one percent of the reduction in CaO2 was explained by the lower inspired O2 pressure (PIO2) in hypoxia, whereas the rest was due to the impairment of the pulmonary gas exchange, as reflected by the higher alveolar-arterial O2 difference in hypoxia (P < 0.05). Hypoxia caused a 47% decrease in VO2 max (a greater fall than accountable by reduced CaO2). Peak cardiac output decreased by 17% (P < 0.01), due to equal reductions in both peak heart rate and stroke volume (P < 0.05). Peak leg blood flow was also lower (by 22%, P < 0.01). Consequently, systemic and leg O2 delivery were reduced by 43 and 47%, respectively, with hypoxia (P < 0.001) correlating closely with VO2 max (r = 0.98, P < 0.001). Therefore, three main mechanisms account for the reduction of VO2 max in severe acute hypoxia: 1) reduction of PIO2, 2) impairment of pulmonary gas exchange, and 3) reduction of maximal cardiac output and peak leg blood flow, each explaining about one-third of the loss in VO2 max.

cardiac output; fatigue; performance; cardiovascular physiology


This article has been cited by other articles:


Home page
 J. Appl. Physiol.Home page
D. P. Casey, B. D. Madery, T. L. Pike, J. H. Eisenach, N. M. Dietz, M. J. Joyner, and B. W. Wilkins
Adenosine receptor antagonist and augmented vasodilation during hypoxic exercise
J Appl Physiol, October 1, 2009; 107(4): 1128 - 1137.
[Abstract] [Full Text] [PDF]

Home page
 Am. J. Respir. Crit. Care Med.Home page
M. Fischler, M. Maggiorini, L. Dorschner, J. Debrunner, A. Bernheim, S. Kiencke, H. Mairbaurl, K. E. Bloch, R. Naeije, and H. P. B.-L. Rocca
Dexamethasone But Not Tadalafil Improves Exercise Capacity in Adults Prone to High-Altitude Pulmonary Edema
Am. J. Respir. Crit. Care Med., August 15, 2009; 180(4): 346 - 352.
[Abstract] [Full Text] [PDF]

Home page
 Am. J. Physiol. Regul. Integr. Comp. Physiol.Home page
M. K. Stickland, C. A. Smith, B. J. Soriano, and J. A. Dempsey
Sympathetic restraint of muscle blood flow during hypoxic exercise
Am J Physiol Regulatory Integrative Comp Physiol, May 1, 2009; 296(5): R1538 - R1546.
[Abstract] [Full Text] [PDF]

Home page
 J. Physiol.Home page
J. A. L. Calbet, G. Radegran, R. Boushel, and B. Saltin
On the mechanisms that limit oxygen uptake during exercise in acute and chronic hypoxia: role of muscle mass
J. Physiol., January 15, 2009; 587(2): 477 - 490.
[Abstract] [Full Text] [PDF]

Home page
 J. Appl. Physiol.Home page
R. J. Shephard, C. Foster, A. Lucia, D. R. Bassett, S. M. Marcora, J. Gonzalez-Alonso, S. P. Mortensen, S. S. Cheung, A. D. Flouris, O. J. Kemi, et al.
No support for central governor.
J Appl Physiol, January 1, 2009; 106(1): 343 - 344.
[Full Text] [PDF]

Home page
 J. Physiol.Home page
S. P. Mortensen, R. Damsgaard, E. A. Dawson, N. H. Secher, and J. Gonzalez-Alonso
Restrictions in systemic and locomotor skeletal muscle perfusion, oxygen supply and VO2 during high-intensity whole-body exercise in humans
J. Physiol., May 15, 2008; 586(10): 2621 - 2635.
[Abstract] [Full Text] [PDF]

Home page
 J. Appl. Physiol.Home page
M. Amann and J. A. L. Calbet
Convective oxygen transport and fatigue
J Appl Physiol, March 1, 2008; 104(3): 861 - 870.
[Abstract] [Full Text] [PDF]

Home page
 J. Physiol.Home page
B. W. Wilkins, T. L. Pike, E. A. Martin, T. B. Curry, M. L. Ceridon, and M. J. Joyner
Exercise intensity-dependent contribution of {beta}-adrenergic receptor-mediated vasodilatation in hypoxic humans
J. Physiol., February 15, 2008; 586(4): 1195 - 1205.
[Abstract] [Full Text] [PDF]

Home page
 J. Physiol.Home page
C. Lundby, R. Boushel, P. Robach, K. Moller, B. Saltin, and J. A. L. Calbet
During hypoxic exercise some vasoconstriction is needed to match O2 delivery with O2 demand at the microcirculatory level
J. Physiol., January 1, 2008; 586(1): 123 - 130.
[Abstract] [Full Text] [PDF]

Home page
 Am. J. Physiol. Heart Circ. Physiol.Home page
A. W. Subudhi, M. C. Lorenz, C. S. Fulco, and R. C. Roach
Cerebrovascular responses to incremental exercise during hypobaric hypoxia: effect of oxygenation on maximal performance
Am J Physiol Heart Circ Physiol, January 1, 2008; 294(1): H164 - H171.
[Abstract] [Full Text] [PDF]

Home page
 J. Physiol.Home page
M. Amann, L. M. Romer, and J. A. Dempsey
Reply from Markus Amann, Lee M. Romer and Jerome A. Dempsey
J. Physiol., December 15, 2007; 585(3): 923 - 924.
[Full Text] [PDF]

Home page
 Am. J. Physiol. Regul. Integr. Comp. Physiol.Home page
L. J. Haseler, A. Lin, J. Hoff, and R. S. Richardson
Oxygen availability and PCr recovery rate in untrained human calf muscle: evidence of metabolic limitation in normoxia
Am J Physiol Regulatory Integrative Comp Physiol, November 1, 2007; 293(5): R2046 - R2051.
[Abstract] [Full Text] [PDF]

Home page
 J. Appl. Physiol.Home page
V. Faoro, S. Huez, S. Giltaire, A. Pavelescu, A. van Osta, J.-J. Moraine, H. Guenard, J.-B. Martinot, and R. Naeije
Effects of acetazolamide on aerobic exercise capacity and pulmonary hemodynamics at high altitudes
J Appl Physiol, October 1, 2007; 103(4): 1161 - 1165.
[Abstract] [Full Text] [PDF]

Home page
 J. Appl. Physiol.Home page
T. Ogawa, K. Hayashi, M. Ichinose, and T. Nishiyasu
Relationship between resting ventilatory chemosensitivity and maximal oxygen uptake in moderate hypobaric hypoxia
J Appl Physiol, October 1, 2007; 103(4): 1221 - 1226.
[Abstract] [Full Text] [PDF]

Home page
 J. Appl. Physiol.Home page
A. W. Subudhi, A. C. Dimmen, and R. C. Roach
Effects of acute hypoxia on cerebral and muscle oxygenation during incremental exercise
J Appl Physiol, July 1, 2007; 103(1): 177 - 183.
[Abstract] [Full Text] [PDF]

Home page
 J. Physiol.Home page
M. Amann, L. M. Romer, A. W. Subudhi, D. F. Pegelow, and J. A. Dempsey
Severity of arterial hypoxaemia affects the relative contributions of peripheral muscle fatigue to exercise performance in healthy humans
J. Physiol., May 15, 2007; 581(1): 389 - 403.
[Abstract] [Full Text] [PDF]

Home page
 Am. J. Physiol. Heart Circ. Physiol.Home page
J. Barden, L. Lawrenson, J. G. Poole, J. Kim, D. W. Wray, D. M. Bailey, and R. S. Richardson
Limitations to vasodilatory capacity and VO2 max in trained human skeletal muscle
Am J Physiol Heart Circ Physiol, May 1, 2007; 292(5): H2491 - H2497.
[Abstract] [Full Text] [PDF]

Home page
 J. Physiol.Home page
A. M. Jonk, I. P. van den Berg, I. M. Olfert, D. W. Wray, T. Arai, S. R. Hopkins, and P. D. Wagner
Effect of acetazolamide on pulmonary and muscle gas exchange during normoxic and hypoxic exercise
J. Physiol., March 15, 2007; 579(3): 909 - 921.
[Abstract] [Full Text] [PDF]

Home page
 J. Physiol.Home page
M. Amann, M. W. Eldridge, A. T. Lovering, M. K. Stickland, D. F. Pegelow, and J. A. Dempsey
Arterial oxygenation influences central motor output and exercise performance via effects on peripheral locomotor muscle fatigue in humans
J. Physiol., September 15, 2006; 575(3): 937 - 952.
[Abstract] [Full Text] [PDF]

Home page
 J. Physiol.Home page
J. A. L. Calbet
The rate of fatigue accumulation as a sensed variable
J. Physiol., September 15, 2006; 575(3): 688 - 689.
[Full Text] [PDF]

Home page
 Am. J. Physiol. Regul. Integr. Comp. Physiol.Home page
J. A. L. Calbet, C. Lundby, M. Sander, P. Robach, B. Saltin, and R. Boushel
Effects of ATP-induced leg vasodilation on VO2 peak and leg O2 extraction during maximal exercise in humans
Am J Physiol Regulatory Integrative Comp Physiol, August 1, 2006; 291(2): R447 - R453.
[Abstract] [Full Text] [PDF]

Home page
 Exp PhysiolHome page
M. Burnley, C. L. Roberts, R. Thatcher, J. H. Doust, and A. M. Jones
Influence of blood donation on O2 uptake on-kinetics, peak O2 uptake and time to exhaustion during severe-intensity cycle exercise in humans
Exp Physiol, May 1, 2006; 91(3): 499 - 509.
[Abstract] [Full Text] [PDF]

Home page
 Am. J. Physiol. Regul. Integr. Comp. Physiol.Home page
J. A. L. Calbet, H.-C. Holmberg, H. Rosdahl, G. van Hall, M. Jensen-Urstad, and B. Saltin
Why do arms extract less oxygen than legs during exercise?
Am J Physiol Regulatory Integrative Comp Physiol, November 1, 2005; 289(5): R1448 - R1458.
[Abstract] [Full Text] [PDF]

Home page
 Am. J. Physiol. Regul. Integr. Comp. Physiol.Home page
C. Lundby, J. A. L. Calbet, G. van Hall, B. Saltin, and M. Sander
Pulmonary gas exchange at maximal exercise in Danish lowlanders during 8 wk of acclimatization to 4,100 m and in high-altitude Aymara natives
Am J Physiol Regulatory Integrative Comp Physiol, November 1, 2004; 287(5): R1202 - R1208.
[Abstract] [Full Text] [PDF]

Home page
 Am. J. Physiol. Regul. Integr. Comp. Physiol.Home page
T. D. Noakes, J. A. L. Calbet, R. Boushel, H. Sondergaard, G. Radegran, P. D. Wagner, and B. Saltin
Central regulation of skeletal muscle recruitment explains the reduced maximal cardiac output during exercise in hypoxia
Am J Physiol Regulatory Integrative Comp Physiol, October 1, 2004; 287(4): R996 - R1002.
[Full Text] [PDF]

Home page
 Am. J. Physiol. Heart Circ. Physiol.Home page
J. A. L. Calbet, G. Radegran, R. Boushel, H. Sondergaard, B. Saltin, and P. D. Wagner
Plasma volume expansion does not increase maximal cardiac output or VO2 max in lowlanders acclimatized to altitude
Am J Physiol Heart Circ Physiol, September 1, 2004; 287(3): H1214 - H1224.
[Abstract] [Full Text] [PDF]

Home page
 J. Physiol.Home page
J. A. L. Calbet, M. Jensen-Urstad, G. van Hall, H.-C. Holmberg, H. Rosdahl, and B. Saltin
Maximal muscular vascular conductances during whole body upright exercise in humans
J. Physiol., July 1, 2004; 558(1): 319 - 331.
[Abstract] [Full Text] [PDF]


HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
Visit Other APS Journals Online