|
|
||||||||
Journal of Applied Physiology, Vol 70, Issue 1 55-62, Copyright © 1991 by American Physiological Society
ARTICLES |
C. McParland, J. Mink and C. G. Gallagher
Department of Medicine, University of Saskatchewan, Saskatoon, Canada.
We examined the effects of dead space (VD) loading on breathing pattern during maximal incremental exercise in eight normal subjects. Addition of external VD was associated with a significant increase in tidal volume (VT) and decrease in respiratory frequency (f) at moderate and high levels of ventilation (VI); at a VI of 120 l/min, VT and f with added VD were 3.31 +/- 0.33 liters and 36.7 +/- 6.7 breaths/min, respectively, compared with 2.90 +/- 0.29 liters and 41.8 +/- 7.3 breaths/min without added VD. Because breathing pattern does not change with CO2 inhalation during heavy exercise (Gallagher et al. J. Appl. Physiol. 63: 238-244, 1987), the breathing pattern response to added VD is probably a consequence of alteration in the PCO2 time profile, possibly sensed by the carotid body and/or airway-pulmonary chemoreceptors. The increase in VT during heavy exercise with VD loading indicates that the tachypneic breathing pattern of heavy exercise is not due to mechanical limitation of maximum ventilatory capacity at high levels of VT.
This article has been cited by other articles:
![]() |
E. F. McKone, S. C. Barry, M. X. FitzGerald, and C. G. Gallagher Role of arterial hypoxemia and pulmonary mechanics in exercise limitation in adults with cystic fibrosis J Appl Physiol, September 1, 2005; 99(3): 1012 - 1018. [Abstract] [Full Text] [PDF] |
||||
![]() |
R. N. Khayat, A. Xie, A. K. Patel, A. Kaminski, and J. B. Skatrud Cardiorespiratory Effects of Added Dead Space in Patients With Heart Failure and Central Sleep Apnea Chest, May 1, 2003; 123(5): 1551 - 1560. [Abstract] [Full Text] [PDF] |
||||
![]() |
A. Chauhan, G. Sridhar, R. Clemens, B. Krishnan, D. D. Marciniuk, and C. G. Gallagher Role of Respiratory Function in Exercise Limitation in Chronic Heart Failure Chest, July 1, 2000; 118(1): 53 - 60. [Abstract] [Full Text] [PDF] |
||||
![]() |
D. E. O'Donnell, H. H. Hong, and K. A. Webb Respiratory sensation during chest wall restriction and dead space loading in exercising men J Appl Physiol, May 1, 2000; 88(5): 1859 - 1869. [Abstract] [Full Text] [PDF] |
||||
![]() |
S. R. McClaran, T. J. Wetter, D. F. Pegelow, and J. A. Dempsey Role of expiratory flow limitation in determining lung volumes and ventilation during exercise J Appl Physiol, April 1, 1999; 86(4): 1357 - 1366. [Abstract] [Full Text] [PDF] |
||||
![]() |
T. G. Babb, K. A. Long, and J. R. Rodarte The Relationship Between Maximal Expiratory Flow and Increases of Maximal Exercise Capacity with Exercise Training Am. J. Respir. Crit. Care Med., July 1, 1997; 156(1): 116 - 121. [Abstract] [Full Text] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| Visit Other APS Journals Online |