Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
6
pubmed:dateCreated
1993-2-26
pubmed:abstractText
The reasons for the reduced exercise capacities observed at high altitudes are not completely known. Substrate availability or accumulations of lactate and ammonium could have significant roles. As part of Operation Everest II, peak oxygen uptakes were determined in five normal male volunteers with use of progressively increasing cycling work loads at ambient barometric pressures of 760, 380, and 282 Torr. Decrements from sea level (SL) to 380 and 282 Torr occurred in peak power output (19 and 47%), time to exhaustion (19 and 48%), and oxygen uptake (41 and 61%), respectively. Arterial saturations after exhaustive exercise were decreased to 63% at 380 Torr and 39% at 282 Torr. At 380 and 282 Torr, postexercise plasma concentrations of glucose and free fatty acids were not increased, whereas plasma glycerol concentrations were decreased relative to SL (145 +/- 24 microM at 380 Torr and 77 +/- 10 microM at 282 Torr vs. 213 +/- 24 microM at SL). Preexercise plasma insulin concentrations were elevated at both 380 and 282 Torr (87 +/- 16 pM at 380 Torr and 85 +/- 18 pM at 282 Torr vs. 41 +/- 30 pM at SL). In general, postexercise concentrations of plasma catecholamines were decreased at altitude compared with SL. Preexercise lactate and ammonium concentrations were not different at any simulated altitude. From these data neither substrate availability nor metabolic product accumulation limited exercise capacity at extreme simulated altitude.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Dec
pubmed:issn
8750-7587
pubmed:author
pubmed:issnType
Print
pubmed:volume
73
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
2574-9
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1992
pubmed:articleTitle
Operation Everest II: metabolic and hormonal responses to incremental exercise to exhaustion.
pubmed:affiliation
Altitude Physiology and Medicine Division, United States Army Research Institute of Environmental Medicine, Natick, Massachusetts 01760.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, Non-P.H.S., Research Support, Non-U.S. Gov't