Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
1993-6-4
pubmed:abstractText
Paired frequently sampled intravenous glucose tolerance tests (FSIGT) were performed on five highly trained athletes within 2 hours of completing a 6-day ultramarathon run (E) and after 2 weeks of complete rest (R). Severe exercise increased free fatty acid (FFA) levels (E 1.2 +/- 0.16 v 0.42 +/- 0.07 mmol/L, P < .01) and norepinephrine levels (E 573 +/- 141 v 224 +/- 33 pg/mL, P < .01), with only moderate reductions in glucose tolerance (glucose disappearance [Kg] E 1.06 +/- 0.2 v R 1.7 +/- 0.3 min-1 x 10(2), P < .05). The minimal model analysis of FSIGT data using the method of Bergman et al (Endocr Rev 6:45-86, 1985) showed a reduced second-phase insulin secretion ([phi 2] E 5.2 +/- 1.3 v 13 +/- 2.2 microU/mL.min-2 per mg/dL, P < .05) and glucose disposition index ([SI x phi 2] E 33.8 +/- 10 v 73.9 +/- 11 mg-1.dL.min-3 x 10(4), P < .02). Insulin sensitivity (SI) and glucose-mediated glucose disposal (SG) were unchanged (SI E 6.9 +/- 1.0 v 6.0 +/- 0.6 min-1 per microU/mL x 10(4); SG E 1.8 +/- 0.6 v 1.4 +/- 0.3 min-1 x 10(2)). Reduced glucose tolerance after prolonged extreme physical exercise was accompanied by reduced phi 2 and not by alterations of SI or SG, despite the marked increase of FFA levels. Elevated norepinephrine levels, reflecting activation of the sympathetic noradrenergic system, was also associated with the reduction in Kg. The reduction in phi 2 would promote mobilization of FFA, the predominant metabolic substrate in these endurance events.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Mar
pubmed:issn
0026-0495
pubmed:author
pubmed:issnType
Print
pubmed:volume
42
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
277-82
pubmed:dateRevised
2011-11-17
pubmed:meshHeading
pubmed-meshheading:8487644-Adult, pubmed-meshheading:8487644-Automatic Data Processing, pubmed-meshheading:8487644-Blood Glucose, pubmed-meshheading:8487644-C-Peptide, pubmed-meshheading:8487644-Carbohydrate Metabolism, pubmed-meshheading:8487644-Exercise, pubmed-meshheading:8487644-Fatty Acids, Nonesterified, pubmed-meshheading:8487644-Glucagon, pubmed-meshheading:8487644-Glucose, pubmed-meshheading:8487644-Glucose Tolerance Test, pubmed-meshheading:8487644-Humans, pubmed-meshheading:8487644-Injections, Intravenous, pubmed-meshheading:8487644-Insulin, pubmed-meshheading:8487644-Insulin Resistance, pubmed-meshheading:8487644-Middle Aged, pubmed-meshheading:8487644-Norepinephrine, pubmed-meshheading:8487644-Physical Endurance, pubmed-meshheading:8487644-Radioimmunoassay, pubmed-meshheading:8487644-Rest, pubmed-meshheading:8487644-Running, pubmed-meshheading:8487644-Time Factors
pubmed:year
1993
pubmed:articleTitle
Impaired glucose tolerance after endurance exercise is associated with reduced insulin secretion rather than altered insulin sensitivity.
pubmed:affiliation
Endocrinology Unit, St. Vincent's Hospital, Victoria Parade, Fitzroy, Australia.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't