Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
1981-5-21
pubmed:abstractText
Ventilation (VE) climbs steadily throughout prolonged heavy exercise. While this VE "drift" has implications for the adequacy of gas exchange in long-term exercise, its mechanism remains unknown. We examined the behavior of previously proposed mediators of VE drift during one hour of cycle ergometer exercise at constant work rate requiring 2/3 VO2 max in 10 subjects. VE increased 13% from 12 to 61 min of exercise (P less than 0.05). Although body core temperature rose as VE rose, equal elevation of core temperature by passive means failed to increase exercise VE. Rising VE during the hour of exercise occurred despite unchanged arterial pH, PCO2, and lactate and despite unchanged VCO2. Thus, all of the VE increase was calculated to be due to increased dead space ventilation (VD). Tidal volume (VT) was unchanged, while VD/VT rose from 0.16 to 0.24 from 12 to 61 min of work (P less than 0.05). These results show that increased body core temperature does not mediate VE drift, and that changes in previously proposed mediators (arterial pH, arterial lactate, and VCO2) are not necessary for a slow VE rise to occur in prolonged heavy exercise.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jan
pubmed:issn
0161-7567
pubmed:author
pubmed:issnType
Print
pubmed:volume
50
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
27-31
pubmed:dateRevised
2008-11-21
pubmed:meshHeading
pubmed:year
1981
pubmed:articleTitle
Control of breathing during prolonged exercise.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S.