Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
6
pubmed:dateCreated
1991-10-8
pubmed:abstractText
We analyzed the changes in water content and electrolyte concentrations in the vascular space during graded exercise of short duration. Six male volunteers exercised on a cycle ergometer at 20 degrees C (relative humidity = 30%) as exercise intensity was increased stepwise until voluntary exhaustion. Blood samples were collected at exercise intensities of 29, 56, 70, and 95% of maximum aerobic power (VO2max). A curvilinear relationship between exercise intensity and Na+ concentration in plasma ([Na+]p) was observed. [Na+]p significantly increased at 70% VO2max and at 95% VO2max was approximately 8 meq/kgH2O higher than control. The change in lactate concentration in plasma ([Lac-]p) was closely correlated with the change in [Na+]p (delta[Na+]p = 0.687 delta[Lac-]p + 1.79, r = 0.99). The change in [Lac-]p was also inversely correlated with the change in HCO3- concentration in plasma (delta[HCO3-]p = -0.761 delta[Lac-]p + 0.22, r = -1.00). At an exercise intensity of 95% VO2max, 60% of the increase in plasma osmolality (Posmol) was accounted for by an increase in [Na+]p. These results suggest that lactic acid released into the vascular space from active skeletal muscles reacts with [HCO3-]p to produce CO2 gas and Lac-. The data raise the intriguing notion that increase in [Na+]p during exercise may be caused by elevated Lac-.
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
70
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
2757-62
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1991
pubmed:articleTitle
Water and electrolyte balance in the vascular space during graded exercise in humans.
pubmed:affiliation
Department of Physiology, Kyoto Prefectural University of Medicine, Japan.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't