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Predicate | Object |
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rdf:type | |
lifeskim:mentions | |
pubmed:issue |
2
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pubmed:dateCreated |
1985-1-31
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pubmed:abstractText |
Single breath O2 consumption (PB = 730, FI02 = 0.21) was measured at rest, during 10 min cycloergometric exercise at 125 W, and in the following recovery phase in seven subjects before, and 12 days after 6 weeks at 5,200 m or above. Peak blood lactate after exercise (Lâb) was measured. O2 deficits and debts and half times (t1/2) of the VO2 on- and off-kinetics were calculated. Before acclimatization, the VO2 on- and off-responses were close to a single exponential with t1/2 = 30 s. After return to sea level, the VO2 on-response curves were less steep in the initial phase, becoming closer to sigmoid. The t1/2, independent of the shape of the underlying function, was approximately 10 s longer. The VO2 off-responses during the initial 4 min of recovery were the same before and after acclimatization. Average O2 deficit was approximately 320 ml larger after acclimatization: the fast component of O2 debt was similar. Since steady state VO2 and Lâb were the same, the O2 deficit difference can be attributed to a greater utilization of O2 stores. Of these, about 1/3 is explained in terms of increased mixed venous blood O2 stores, due to increased [Hb] (16.6 vs 14.9 g X dl-1), while the remainder is ascribed essentially to increased Mb-bound O2. O2 stores utilization and replenishment is presumed to occur when muscle metabolism is low; as a consequence, while it is clearly detectable from the shape of the initial phase of the VO2 on-response, during recovery it is spread throughout, thus becoming more difficult to appreciate.
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pubmed:language |
eng
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pubmed:journal | |
pubmed:citationSubset |
IM
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pubmed:chemical | |
pubmed:status |
MEDLINE
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pubmed:issn |
0301-5548
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pubmed:author | |
pubmed:issnType |
Print
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pubmed:volume |
53
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pubmed:owner |
NLM
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pubmed:authorsComplete |
Y
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pubmed:pagination |
87-91
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pubmed:dateRevised |
2008-11-21
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pubmed:meshHeading |
pubmed-meshheading:6542518-Acclimatization,
pubmed-meshheading:6542518-Adult,
pubmed-meshheading:6542518-Altitude Sickness,
pubmed-meshheading:6542518-Anoxia,
pubmed-meshheading:6542518-Humans,
pubmed-meshheading:6542518-Kinetics,
pubmed-meshheading:6542518-Male,
pubmed-meshheading:6542518-Middle Aged,
pubmed-meshheading:6542518-Muscles,
pubmed-meshheading:6542518-Oxygen,
pubmed-meshheading:6542518-Physical Exertion
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pubmed:year |
1984
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pubmed:articleTitle |
After effects of chronic hypoxia on VO2 kinetics and on O2 deficit and debt.
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pubmed:publicationType |
Journal Article,
Research Support, Non-U.S. Gov't
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