| Errors in the estimation of hydration status from changes in body mass. | |
| | |
MedLine Citation:
|
PMID: 17454547 Owner: NLM Status: MEDLINE |
Abstract/OtherAbstract:
|
Hydration status is not easily measured, but acute changes in hydration status are often estimated from body mass change. Changes in body mass are also often used as a proxy measure for sweat losses. There are, however, several sources of error that may give rise to misleading results, and our aim in this paper is to quantify these potential errors. Respiratory water losses can be substantial during hard work in dry environments. Mass loss also results from substrate oxidation, but this generates water of oxidation which is added to the body water pool, thus dissociating changes in body mass and hydration status: fat oxidation actually results in a net gain in body mass as the mass of carbon dioxide generated is less than the mass of oxygen consumed. Water stored with muscle glycogen is presumed to be made available as endogenous carbohydrate stores are oxidized. Fluid ingestion and sweat loss complicate the picture by altering body water distribution. Loss of hypotonic sweat results in increased osmolality of body fluids. Urine and faecal losses can be measured easily, but changes in the water content of the bladder and the gastrointestinal tract cannot. Body mass change is not always a reliable measure of changes in hydration status and substantial loss of mass may occur without an effective net negative fluid balance. |
| | |
Authors:
|
Ronald J Maughan; Susan M Shirreffs; John B Leiper |
Related Documents
:
|
3273627 - A simple method for concentrating erythropoietin activity in plasma and in other body f... 23088587 - Measuring aqueous solubility in the presence of small cosolvent volume fractions by pas... 14728617 - In situ measured elimination of vibrio cholerae from brackish water. 7299997 - The processed map of the body surface potential. 23592007 - Silanization of quartz, silicon and mica surfaces with light-driven molecular motors: c... 20673597 - Comments on "analytical modelling of fringe and core biodegradation in groundwater plum... |
Publication Detail:
|
Type: Journal Article |
Journal Detail:
|
Title: Journal of sports sciences Volume: 25 ISSN: 0264-0414 ISO Abbreviation: J Sports Sci Publication Date: 2007 May |
Date Detail:
|
Created Date: 2007-04-24 Completed Date: 2007-06-26 Revised Date: 2008-12-31 |
Medline Journal Info:
|
Nlm Unique ID: 8405364 Medline TA: J Sports Sci Country: England |
Other Details:
|
Languages: eng Pagination: 797-804 Citation Subset: IM |
Affiliation:
|
School of Sport and Exercise Sciences, Loughborough University, Loughborough, UK. r.maughan@lboro.ac.uk |
Export Citation:
|
APA/MLA Format Download EndNote Download BibTex |
| MeSH Terms | |
Descriptor/Qualifier:
|
Body Mass Index* Dehydration / physiopathology, prevention & control* Drinking* Glycogen Great Britain Health Status Indicators* Humans Reproducibility of Results Water Water Loss, Insensible / physiology |
| Chemical | |
Reg. No./Substance:
|
7732-18-5/Water; 9005-79-2/Glycogen |
| Comments/Corrections | |
Erratum In:
|
J Sports Sci. 2008 Sep;26(11):1245 |
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine
Previous Document: Drinking guidelines for exercise: what evidence is there that athletes should drink "as much as tole...
Next Document: Activity profile of top-class association football referees in relation to performance in selected p...