Document Detail

Oxygen transport to exercising leg in chronic hypoxia.
MedLine Citation:
PMID:  3215859     Owner:  NLM     Status:  MEDLINE    
Residence at high altitude could be accompanied by adaptations that alter the mechanisms of O2 delivery to exercising muscle. Seven sea level resident males, aged 22 +/- 1 yr, performed moderate to near-maximal steady-state cycle exercise at sea level in normoxia [inspired PO2 (PIO2) 150 Torr] and acute hypobaric hypoxia (barometric pressure, 445 Torr; PIO2, 83 Torr), and after 18 days' residence on Pikes Peak (4,300 m) while breathing ambient air (PIO2, 86 Torr) and air similar to that at sea level (35% O2, PIO2, 144 Torr). In both hypoxia and normoxia, after acclimatization the femoral arterial-iliac venous O2 content difference, hemoglobin concentration, and arterial O2 content, were higher than before acclimatization, but the venous PO2 (PVO2) was unchanged. Thermodilution leg blood flow was lower but calculated arterial O2 delivery and leg VO2 similar in hypoxia after vs. before acclimatization. Mean arterial pressure (MAP) and total peripheral resistance in hypoxia were greater after, than before, acclimatization. We concluded that acclimatization did not increase O2 delivery but rather maintained delivery via increased arterial oxygenation and decreased leg blood flow. The maintenance of PVO2 and the higher MAP after acclimatization suggested matching of O2 delivery to tissue O2 demands, with vasoconstriction possibly contributing to the decreased flow.
P R Bender; B M Groves; R E McCullough; R G McCullough; S Y Huang; A J Hamilton; P D Wagner; A Cymerman; J T Reeves
Related Documents :
2445179 - Critical oxygen delivery levels during shock following normoxic and hyperoxic haemodilu...
10632449 - Effects of low oxygen concentrations and metabolic inhibitors on proteoglycan and prote...
1757299 - Maximum oxygen uptake and arterial blood oxygenation during hypoxic exercise in rats.
15734689 - Ascent exhalations of antarctic fur seals: a behavioural adaptation for breath-hold div...
24704179 - Assessment of mobile device and sms use for diet and exercise information among rural m...
15665059 - Estimating oxygen consumption rates of arteriolar walls under physiological conditions ...
15581919 - Dynamics of accommodative fatigue in rhesus monkeys and humans.
19387369 - Influence of exercise order on oxygen uptake during strength training in young women.
6840519 - Effect of the photoperiod on the time schedule of egg mass production in lymnaea stagna...
Publication Detail:
Type:  Journal Article; Research Support, U.S. Gov't, P.H.S.    
Journal Detail:
Title:  Journal of applied physiology (Bethesda, Md. : 1985)     Volume:  65     ISSN:  8750-7587     ISO Abbreviation:  J. Appl. Physiol.     Publication Date:  1988 Dec 
Date Detail:
Created Date:  1989-03-09     Completed Date:  1989-03-09     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:  2592-7     Citation Subset:  IM; S    
Cardiovascular Pulmonary Research Laboratory, University of Colorado Health Sciences Center, Denver, 80262.
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Anoxia / blood*
Biological Transport, Active
Blood Flow Velocity
Leg / blood supply
Oxygen / blood*
Oxygen Consumption
Physical Exertion*
Grant Support
Reg. No./Substance:

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

Previous Document:  Effect of hemodilution on ventilatory fluctuations of pulmonary capillary blood volume.
Next Document:  Enzymatic estimation of skeletal muscle damage by analysis of changes in serum creatine kinase.