HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text Full Text (PDF) All Versions of this Article: 90/3/357    most recent expphysiol.2004.028779v1 Alert me when this article is cited Alert me if a correction is posted Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Bell, H. J. Articles by Duffin, J. Search for Related Content PubMed PubMed Citation Articles by Bell, H. J. Articles by Duffin, J. Related Collections Respiratory

¹ Department of Physiology³ Department of Anaesthesia, Medical Sciences Building, King's College Circle, University of Toronto, Canada² Faculty of Medical Sciences, MWF-complex, A. Deusinglaan 1, University of Groningen, the Netherlands

Increased wakefulness is known to suppress the initial ventilatory response to passive movement and the steady-state ventilatory response to exercise. However, the effect of increased wakefulness upon the integrated ventilatory response at the onset of exercise is not known. We hypothesized that increasing wakefulness via a cognitive task would attenuate the initial ventilatory response to exercise, and so we examined the response to active leg extensions under two conditions: with and without concurrently solving a puzzle. At rest before exercise, subjects demonstrated greater minute ventilation while solving a puzzle (mean ±S.E.M., 12.38 ± 0.55 versus 10.12 ± 0.51 l min^–1, P < 0.001), due to a higher mean breathing frequency (mean ±S.E.M., 17.1 ± 0.93 versus 13.6 ± 0.59 breaths min^–1, P < 0.001). At the start of exercise, subjects did not increase their ventilation significantly while solving the puzzle (P= 0.170), but did by a mean ±S.E.M. of 6.16 ± 1.12 l min^–1 (P < 0.001) when not puzzle solving. The ventilation achieved at the start of exercise in absolute terms was also lower while solving the puzzle (14.6 ± 1.1 versus 16.3 ± 1.3 l min^–1, P= 0.047). Despite differences in the rapid ventilatory response to exercise between conditions, the steady-state responses were not different. We conclude that the performance of a cognitive task decreases the initial phase of exercise hyperpnoea, and suggest that this might occur because of either a competitive interaction between drives to breathe or a behavioural distraction from the ‘task’ of exercise.

(Received 30 July 2004; accepted after revision 19 January 2005; first published online 21 January 2005)
Corresponding author J. Duffin: Department of Physiology, University of Toronto, 1 King's College Circle, Toronto, Ontario, Canada M5S 1A8. Email: j.duffin{at}utoronto.ca

This article has been cited by other articles:

				F. L. Eldridge, D. Morin, J. R. Romaniuk, S. Yamashiro, J. T. Potts, R. M. Ichiyama, H. Bell, E. A. Phillipson, K. J. Killian, N. L. Jones, et al. Comment on Point:Counterpoint "Supraspinal locomotor centers do/do not contribute significantly to the hyperpnea of dynamic exercise in humans" J Appl Physiol, May 1, 2006; 100(5): 1743 - 1747. [Full Text] [PDF]

				N. H. Secher, C.-S. Poon, S. A. Ward, B. J. Whipp, and J. Duffin Comment on Point:Counterpoint "Supraspinal locomotor centers do/do not contribute significantly to the hyperpnea of dynamic exercise in humans" J Appl Physiol, April 1, 2006; 100(4): 1417 - 1417. [Full Text] [PDF]