Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
6
pubmed:dateCreated
1999-8-2
pubmed:abstractText
In skeletal muscle, phosphocreatine (PCr) recovery from submaximal exercise has become a reliable and accepted measure of muscle oxidative capacity. During exercise, O2 availability plays a role in determining maximal oxidative metabolism, but the relationship between O2 availability and oxidative metabolism measured by 31P-magnetic resonance spectroscopy (MRS) during recovery from exercise has never been studied. We used 31P-MRS to study exercising human gastrocnemius muscle under conditions of varied fractions of inspired O2 (FIO2) to test the hypothesis that varied O2 availability modulates PCr recovery from submaximal exercise. Six male subjects performed three bouts of 5-min steady-state submaximal plantar flexion exercise followed by 5 min of recovery in a 1.5-T magnet while breathing three different FIO2 concentrations (0.10, 0. 21, and 1.00). Under each FIO2 treatment, the PCr recovery time constants were significantly different, being longer in hypoxia [33. 5 +/- 4.1 s (SE)] and shorter in hyperoxia (20.0 +/- 1.8 s) than in normoxia (25.0 +/- 2.7 s) (P </= 0.05). End-exercise pH was not significantly different among the three treatments (7.08 +/- 0.01 for 0.10, 7.04 +/- 0.01 for 0.21, and 7.04 +/- 0.02 for 1.00). These results demonstrate that PCr recovery is significantly altered by FIO2 and suggest that, after submaximal exercise, PCr recovery, under normoxic conditions, is limited by O2 availability.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jun
pubmed:issn
8750-7587
pubmed:author
pubmed:issnType
Print
pubmed:volume
86
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
2013-8
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1999
pubmed:articleTitle
Skeletal muscle phosphocreatine recovery in exercise-trained humans is dependent on O2 availability.
pubmed:affiliation
Department of Medicine, University of California, San Diego, La Jolla, California 92093-0623, USA. lhaseler@ucsd.edu
pubmed:publicationType
Journal Article, Clinical Trial, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't