Document Detail

Ventilatory and perceptual responses to cycle exercise in obese women.
MedLine Citation:
PMID:  17234804     Owner:  NLM     Status:  MEDLINE    
The main purpose of this study was to examine the relative contribution of respiratory mechanical factors and the increased metabolic cost of locomotion to exertional breathlessness in obese women. We examined the relationship of intensity of breathlessness to ventilation (VE) when exertional oxygen uptake (VO2) of obesity was minimized by cycle exercise. Eighteen middle-aged (54+/-8 yr, mean+/-SD) obese [body mass index (BMI) 40.2+/-7.8 kg/m2] and 13 age-matched normal-weight (BMI 23.3+/-1.7 kg/m2) women were studied. Breathlessness at higher submaximal cycle work rates was significantly increased (by>or=1 Borg unit) in obese compared with normal-weight women, in association with a 35-45% increase in Ve and a higher metabolic cost of exercise. Obese women demonstrated greater resting expiratory flow limitation, reduced resting end-expiratory lung volume (EELV)(by 20%), and progressive increases in dynamic EELV during exercise: peak inspiratory capacity (IC) decreased by 16% (0.39 liter) of the resting value. VE/VO2 slopes were unchanged in obesity. Breathlessness ratings at any given VE or VO2 were not increased in obesity, suggesting that respiratory mechanical factors were not contributory. Our results indicate that in obese women, recruitment of resting IC and dynamic increases in EELV with exercise served to optimize operating lung volumes and to attenuate expiratory flow limitation so as to accommodate the increased ventilatory demand without increased breathlessness.
Dror Ofir; Pierantonio Laveneziana; Katherine A Webb; Denis E O'Donnell
Related Documents :
6986534 - Effects of acute exercise on insulin binding to monocytes in obesity.
741204 - Exercise energy expenditure in extreme obesity: influence of ergometry type and weight ...
12688454 - Exercise load index and changes in body weight during long-duration confinement in an i...
19910934 - Primary care providers' knowledge, practices, and perceived barriers to the treatment a...
1001314 - Influence of growth and athletic training on heart and lung functions.
3135304 - Fetal breathing adaptation to prolonged hypoxaemia in sheep.
Publication Detail:
Type:  Journal Article; Research Support, Non-U.S. Gov't     Date:  2007-01-18
Journal Detail:
Title:  Journal of applied physiology (Bethesda, Md. : 1985)     Volume:  102     ISSN:  8750-7587     ISO Abbreviation:  J. Appl. Physiol.     Publication Date:  2007 Jun 
Date Detail:
Created Date:  2007-06-06     Completed Date:  2007-11-05     Revised Date:  2013-09-26    
Medline Journal Info:
Nlm Unique ID:  8502536     Medline TA:  J Appl Physiol (1985)     Country:  United States    
Other Details:
Languages:  eng     Pagination:  2217-26     Citation Subset:  IM    
Respiratory Investigation Unit, Department of Medicine, Queen's University, 102 Stuart St., Kingston, Ontario, Canada K7L 2V6.
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Aged, 80 and over
Dyspnea / complications*,  physiopathology*
Exercise Test
Middle Aged
Models, Biological*
Obesity / complications*,  physiopathology*
Oxygen / metabolism
Oxygen Consumption
Physical Exertion*
Respiratory Mechanics*
Reg. No./Substance:
Comment In:
J Appl Physiol (1985). 2007 Jun;102(6):2090-1   [PMID:  17332273 ]

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine

Previous Document:  Physical activity energy expenditure may mediate the relationship between plasma leptin levels and w...
Next Document:  Fat metabolism and acute resistance exercise in trained men.