| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
|
|
|
|||||||
|
|||||||||
Copenhagen Muscle Research Center, Department of Anesthesia, Rigshospitalet, University of Copenhagen, 2100 Copenhagen Ø, Denmark
The combined effects of hyperventilation and
arterial desaturation on cerebral oxygenation
(ScO2)
were determined using near-infrared spectroscopy. Eleven competitive
oarsmen were evaluated during a 6-min maximal ergometer row. The study
was randomized in a double-blind fashion with an inspired
O2 fraction of 0.21 or 0.30 in a
crossover design. During exercise with an inspired
O2 fraction of 0.21, the arterial
CO2 pressure (35 ± 1 mmHg;
mean ± SE) and O2 pressure (77 ± 2 mmHg) as well as the hemoglobin saturation (91.9 ± 0.7%) were reduced (P < 0.05).
ScO2 was
reduced from 80 ± 2 to 63 ± 2%
(P < 0.05), and the near-infrared
spectroscopy-determined concentration changes in deoxy- (
Hb) and
oxyhemoglobin (HbO2) of the
vastus lateralis muscle increased 22 ± 3 µM and decreased 14 ± 3 µM, respectively (P < 0.05). Increasing the inspired O2
fraction to 0.30 did not affect ventilation (174 ± 4 l/min), but
arterial CO2 pressure (37 ± 2 mmHg), O2 pressure (165 ± 5 mmHg), and hemoglobin O2
saturation (99 ± 0.1%) increased
(P < 0.05).
ScO2 remained close to the resting level during exercise (79 ± 2 vs. 81 ± 2%), and although the muscle Hb (18 ± 2 µM) and
HbO2 (
12 ± 3 µM) were similar to those established without
O2 supplementation, work capacity
increased from 389 ± 11 to 413 ± 10 W
(P < 0.05). These results indicate
that an elevated inspiratory O2
fraction increases exercise performance related to maintained cerebral oxygenation rather than to an effect on the working muscles.
arterial oxygen saturation; arterial oxygen pressure; hyperoxia; lactate; near-infrared spectroscopy; pH
This article has been cited by other articles:
|
|
 |
|
  S. Ogoh and P. N. Ainslie Cerebral blood flow during exercise: mechanisms of regulation J Appl Physiol, November 1, 2009; 107(5): 1370 - 1380. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
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]
|
|
|
|
|
|
N. H. Secher, T. Seifert, and J. J. Van Lieshout Cerebral blood flow and metabolism during exercise: implications for fatigue J Appl Physiol, January 1, 2008; 104(1): 306 - 314. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 S. Volianitis, A. Fabricius-Bjerre, A. Overgaard, M. Stromstad, M. Bjarrum, C. Carlson, N. T. Petersen, P. Rasmussen, N. H. Secher, and H. B. Nielsen The cerebral metabolic ratio is not affected by oxygen availability during maximal exercise in humans J. Physiol., January 1, 2008; 586(1): 107 - 112. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 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]
|
|
|
|
|
|
H. B. Nielsen, M. A. Febbraio, P. Ott, P. Krustrup, and N. H. Secher Hepatic lactate uptake versus leg lactate output during exercise in humans J Appl Physiol, October 1, 2007; 103(4): 1227 - 1233. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
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]
|
|
|
|
|
|
R. S. Mazzeo, N. H. Secher, P. Rasmussen, B. Kayser, P. D. Wagner, M. Samaja, M. Guazzi, B. Grassi, M. Marzorati, B. Kayser, et al. Comments on Point:Counterpoint: "The lactate paradox does/does not occur during exercise at high altitude" J Appl Physiol, June 1, 2007; 102(6): 2403 - 2405. [Full Text] [PDF]
|
|
|
|
|
|
E. Hart, E. Dawson, P. Rasmussen, K. George, N. H. Secher, G. Whyte, and R. Shave {beta}-Adrenergic receptor desensitization in man: insight into post-exercise attenuation of cardiac function J. Physiol., December 1, 2006; 577(2): 717 - 725. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
I. Vogiatzis, O. Georgiadou, I. Giannopoulou, M. Koskolou, S. Zakynthinos, K. Kostikas, E. Kosmas, H. Wagner, E. Peraki, A. Koutsoukou, et al. Effects of exercise-induced arterial hypoxaemia and work rate on diaphragmatic fatigue in highly trained endurance athletes J. Physiol., April 15, 2006; 572(2): 539 - 549. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 L. M. Romer, H. C. Haverkamp, A. T. Lovering, D. F. Pegelow, and J. A. Dempsey Effect of exercise-induced arterial hypoxemia on quadriceps muscle fatigue in healthy humans Am J Physiol Regulatory Integrative Comp Physiol, February 1, 2006; 290(2): R365 - R375. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
C. H. E. Imray, S. D. Myers, K. T. S. Pattinson, A. R. Bradwell, C. W. Chan, S. Harris, P. Collins, A. D. Wright, and the Birmingham Medical Research Expeditionary Soci Effect of exercise on cerebral perfusion in humans at high altitude J Appl Physiol, August 1, 2005; 99(2): 699 - 706. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 G Naulaers, G Morren, S Van Huffel, P Casaer, and H Devlieger Cerebral tissue oxygenation index in very premature infants Arch. Dis. Child. Fetal Neonatal Ed., November 1, 2002; 87(3): F189 - 192. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
H. B. Nielsen, P. P. Bredmose, M. Stromstad, S. Volianitis, B. Quistorff, and N. H. Secher Bicarbonate attenuates arterial desaturation during maximal exercise in humans J Appl Physiol, August 1, 2002; 93(2): 724 - 731. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 G. Jensen, H. B. Nielsen, K. Ide, P. L. Madsen, L. B. Svendsen, U. G. Svendsen, and N. H. Secher Cerebral Oxygenation During Exercise in Patients With Terminal Lung Disease* Chest, August 1, 2002; 122(2): 445 - 450. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
H. B. Nielsen, J. O. Clemmesen, C. Skak, P. Ott, and N. H. Secher Attenuated hepatosplanchnic uptake of lactate during intense exercise in humans J Appl Physiol, April 1, 2002; 92(4): 1677 - 1683. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
J. J. Hamann, K. M. Kelley, and L. B. Gladden Effect of epinephrine on net lactate uptake by contracting skeletal muscle J Appl Physiol, December 1, 2001; 91(6): 2635 - 2641. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
K. Ide, A. Horn, and N. H. Secher Cerebral metabolic response to submaximal exercise J Appl Physiol, November 1, 1999; 87(5): 1604 - 1608. [Abstract] [Full Text] [PDF]
|
|
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| Visit Other APS Journals Online |
