Document Detail

Expiratory flow limitation during exercise in prepubescent boys and girls: prevalence and implications.
MedLine Citation:
PMID:  20203071     Owner:  NLM     Status:  MEDLINE    
The purpose of this study was to compare the prevalence and implications of expiratory flow limitation (EFL) during exercise in boys and girls. Forty healthy, prepubescent boys (B; n=20) and girls (G; n=20) were tested. Subjects completed pulmonary function tests and an incremental cycle maximal oxygen uptake (VO2max) test. EFL was recorded at the end of each exercise stage using the % tidal volume overlap method. Ventilatory and metabolic data were recorded throughout exercise. Arterial oxygen saturation (SpO2) was determined via pulse oximetry. Body composition was determined using dual-energy X-ray absorptiometry. There were no differences (P>0.05) in height, weight, or body composition between boys and girls. At rest, boys had significantly higher lung volumes (total lung capacity, B=2.6+/-0.5 liters, G=2.1+/-0.5 liters) and peak expiratory flow rates (B=3.6+/-0.6 l/s; G=1.6+/-0.3 l/s). Boys also had significantly higher VO2max (B=46.9+/-5.9 lean body mass(-1).min(-1), G=41.7+/-6.6 lean body mass(-1).min(-1)) and maximal ventilation (B=49.8+/-8.8 l/min, G=41.2+/-8.3 l/min) compared with girls. There were no sex differences (P>0.05) at VO2max in VE /VCO2, end-tidal PCO2, heart rate, respiratory exchange ratio, or SpO2. The prevalence (B=19/20 vs. G=18/20) and severity (B=58+/-7% vs. G=43+/-8% tidal volume) of EFL was not significantly different in boys compared with girls at VO2max. A significant relationship existed between % EFL at VO2max and the change in end-expiratory lung volume from rest to maximal exercise in boys (r=0.77) and girls (r=0.75). In summary, our data suggests that EFL is highly and equally prevalent in prepubescent boys and girls during heavy exercise, which led to an increased end-expiratory lung volume but not to decreases in arterial oxygen saturation.
Katherine E Swain; Sara K Rosenkranz; Bethany Beckman; Craig A Harms
Publication Detail:
Type:  Comparative Study; Journal Article     Date:  2010-03-04
Journal Detail:
Title:  Journal of applied physiology (Bethesda, Md. : 1985)     Volume:  108     ISSN:  1522-1601     ISO Abbreviation:  J. Appl. Physiol.     Publication Date:  2010 May 
Date Detail:
Created Date:  2010-05-05     Completed Date:  2010-08-12     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:  1267-74     Citation Subset:  IM    
Department of Kinesiology, Kansas State University, Manhattan, KS 66506, USA.
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MeSH Terms
Absorptiometry, Photon
Age Factors
Body Composition
Exercise Test
Lung / anatomy & histology,  physiology*
Oxygen / blood
Oxygen Consumption
Pulmonary Ventilation*
Respiratory Function Tests
Sex Factors
Sexual Development*
Tidal Volume
Total Lung Capacity
Reg. No./Substance:

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

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