Journal of Applied Physiology Ad Instruments
HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH
QUICK SEARCH:   [advanced]


     

J Appl Physiol (November 2, 2006). doi:10.1152/japplphysiol.00641.2006
This Article
Right arrow Full Text (PDF) Free
Right arrow All Versions of this Article:
102/2/681    most recent
00641.2006v1
Right arrow Submit a response
Right arrow Alert me when this article is cited
Right arrow Alert me when eLetters are posted
Right arrow Alert me if a correction is posted
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
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 Google Scholar
Google Scholar
Right arrow Articles by Scott, J. M.
Right arrow Articles by Warburton, D. E. R.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Scott, J. M.
Right arrow Articles by Warburton, D. E. R.
Submitted on June 7, 2006
Accepted on October 26, 2006

Gender Differences in Left Ventricular Function and Beta-Receptor Responsiveness Following Prolonged Strenuous Exercise

Jessica M. Scott1, Ben T.A. Esch1, Mark J. Haykowsky2, Saul Isserow3, Michael S. Koehle4, Bevan G. Hughes5, Dominik Zbogar1, Shannon S.D. Bredin1, Don C. McKenzie4, and Darren E. R. Warburton1*

1 Cardiovascular Physiology and Rehabilitation Laboratory, University of British Columbia, Vancouver, Canada
2 Department of Physical Therapy, Faculty of Rehabilitation Medicine, University of Alberta, Edmonton, Alberta, Canada
3 Faculty of Medicine, University of British Columbia, Vancouver, Canada
4 Human Kinetics, University of British Columbia, Vancouver, Canada
5 Vancouver, Canada; Faculty of Medicine, University of British Columbia, Vancouver, Canada

* To whom correspondence should be addressed. E-mail: darrenwb{at}interchange.ubc.ca.

Gender differences in neuroendocrine and metabolic responses to prolonged strenuous exercise (PSE) have been well documented. The aim of this investigation was to examine gender differences in left ventricular function and cardiac {beta}-receptor responsiveness following PSE. Nine male and eight female triathletes were examined during three separate sessions: before, immediately after, and 24 h following a half-ironman triathlon using dobutamine stress echocardiography. Steady-state graded infusions of dobutamine were used to assess {beta}-receptor responsiveness. Slopes calculated from linear regressions between dobutamine doses and changes in heart rate and contractility for each participant were used as an index of {beta}-receptor responsiveness. Despite no change in preload, fractional area change decreased from baseline after the race in both males and females, with a greater decrease in males (males: 54.1 ± 2.1 to 50.7 ± 3.4 % vs. females: 55.4 ± 2.7 to 53.3 ± 2.5 %; p<0.05). The amount of dobutamine necessary to increase HR 25 beats/min (males: 29.6 ± 6.6 to 42.7 ± 12.9 µg/kg/min vs. females: 23.5 ± 4.0 to 30.0 ± 7.8 µg/kg/min; p<0.05) and contractility 10 mmHg/cm2 (males: 20.9 ± 5.1 to 37.0 ± 11.5 µg/kg/min vs. females: 22.6 ± 6.4 to 30.7 ± 7.2 µg/kg/min; p<0.05) was greater in both males and females post-race. However, the amount of dobutamine required to induce these changes was greater in males. These data suggest that following an acute bout of PSE, male triathletes demonstrate a markedly attenuated chronotropic and inotropic response to {beta}-adrenergic stimulation compared with female triathletes.




This article has been cited by other articles:


Home page
 Eur J EchocardiogrHome page
K. George, R. Shave, D. Oxborough, T. Cable, E. Dawson, N. Artis, D. Gaze, T. Hew-Butler, K. Sharwood, and T. Noakes
Left ventricular wall segment motion after ultra-endurance exercise in humans assessed by myocardial speckle tracking
Eur J Echocardiogr, March 1, 2009; 10(2): 238 - 243.
[Abstract] [Full Text] [PDF]

Home page
 J. Appl. Physiol.Home page
B. T. Esch and D. E. R. Warburton
Left ventricular torsion and recoil: implications for exercise performance and cardiovascular disease
J Appl Physiol, February 1, 2009; 106(2): 362 - 369.
[Abstract] [Full Text] [PDF]

Home page
 J. Appl. Physiol.Home page
Rebuttal from Drs. Warburton and Gledhill
J Appl Physiol, January 1, 2008; 104(1): 279 - 280.
[Full Text] [PDF]


HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH
Visit Other APS Journals Online
Copyright © 1948 by the American Physiological Society.