Measured specific gravity, predicted specific gravity and total body water relationships in normal young men

1970 ◽  
Vol 28 (2) ◽  
pp. 79-85 ◽  
Author(s):  
Ronald G. Early ◽  
B. Robert Carlson ◽  
S. W. Casner
Keyword(s):  
Specific Gravity ◽  
Total Body Water ◽  
Young Men ◽  
Body Water ◽  
Total Body

scholarly journals Adaptation and Validation of the Hydration Status Questionnaire in a Spanish Adolescent-Young Population: A Cross Sectional Study

Nutrients ◽  
2019 ◽  
Vol 11 (3) ◽  
pp. 565 ◽  
Author(s):  
Ana Isabel Laja García ◽  
Maria de Lourdes Samaniego-Vaesken ◽  
Teresa Partearroyo ◽  
Gregorio Varela-Moreiras
Keyword(s):  
Specific Gravity ◽  
Water Intake ◽  
Total Body Water ◽  
Body Water ◽  
Urine Specific Gravity ◽  
Hydration Status ◽  
Young Population ◽  
Dietary Record ◽  
Adequate Hydration ◽  
Total Body

The achievement of adequate hydration status is essential for mental and physical performance and for health in general, especially in children and adolescents. Nevertheless, little is known about hydration status of this population, mainly due to the limited availability of research tools; thus, the objective of the current study was to adapt and validate our hydration status questionnaire in a Spanish adolescent-young population. The questionnaire was validated against important hydration markers: urine colour, urine specific gravity, haemoglobin, haematocrit and total body water and involved 128 subjects aged between 12–17 years. Water intake was also estimated through a three-day dietary record and physical activity was assessed through accelerometers. Participants completed the questionnaire twice. Water balance and water intake were correlated with urine specific gravity and with total body water content. Water intake obtained by the questionnaire was correlated with results from the three-day dietary record. The intraclass correlation coefficient indicated moderate concordance between both recordings and the Cronbach’s alpha revealed high consistency. The Bland and Altman method indicated that the limits of agreement were acceptable to reveal the reliability of the estimated measures. In conclusion, this is the first time that a questionnaire is valid and reliable to estimate hydration status of adolescent-young populations.

HEMATOLOGICAL AND BODY FLUID ADJUSTMENTS DURING ACCLIMATION TO A COLD ENVIRONMENT

1956 ◽  
Vol 34 (5) ◽  
pp. 959-966 ◽  
Author(s):  
C. Deb ◽  
J. S. Hart
Keyword(s):  
Body Weight ◽  
Specific Gravity ◽  
Total Body Water ◽  
Body Fluid ◽  
Extracellular Fluid ◽  
Body Water ◽  
Cold Environment ◽  
Cell Counts ◽  
Total Body ◽  
Absolute Basis

Body fluid volumes and hematological values have been compared in rats exposed to 6 °C. for various periods of time and in rats at 30 °C. for comparable periods. Absolute blood and plasma volumes (T1824 space) decreased with time of exposure to 30 °C, while extracellular fluid volume (sodium space), total body water, and body weight increased. Rats transferred from the warm to the cold environment had larger plasma and blood volumes than those of rats at 30 °C. after the first week of exposure. After five weeks, blood volume was 22% greater on an absolute basis and 30% greater relative to total body water than that of the larger rats at 30 °C. There were no differences in extracellular fluid volumes between warm and cold exposed rats at comparable intervals. Total water and intracellular water tended to be greater in rats at 30 °C. on an absolute basis but they were much greater per unit body weight in rats at 6 °C. No differences were observed in red blood cell counts, in hemoglobin concentration, or in plasma specific gravity between warm and cold exposed rats, but there was an increased hematocrit, increased corpuscular volume, and decreased corpuscular hemoglobin content in rats kept at 6 °C. Hemoglobin, red cells, and plasma specific gravity increased with time in both groups.

HEMATOLOGICAL AND BODY FLUID ADJUSTMENTS DURING ACCLIMATION TO A COLD ENVIRONMENT

1956 ◽  
Vol 34 (1) ◽  
pp. 959-966 ◽  
Author(s):  
C. Deb ◽  
J. S. Hart
Keyword(s):  
Body Weight ◽  
Specific Gravity ◽  
Total Body Water ◽  
Body Fluid ◽  
Extracellular Fluid ◽  
Body Water ◽  
Cold Environment ◽  
Cell Counts ◽  
Total Body ◽  
Absolute Basis

Body fluid volumes and hematological values have been compared in rats exposed to 6 °C. for various periods of time and in rats at 30 °C. for comparable periods. Absolute blood and plasma volumes (T1824 space) decreased with time of exposure to 30 °C, while extracellular fluid volume (sodium space), total body water, and body weight increased. Rats transferred from the warm to the cold environment had larger plasma and blood volumes than those of rats at 30 °C. after the first week of exposure. After five weeks, blood volume was 22% greater on an absolute basis and 30% greater relative to total body water than that of the larger rats at 30 °C. There were no differences in extracellular fluid volumes between warm and cold exposed rats at comparable intervals. Total water and intracellular water tended to be greater in rats at 30 °C. on an absolute basis but they were much greater per unit body weight in rats at 6 °C. No differences were observed in red blood cell counts, in hemoglobin concentration, or in plasma specific gravity between warm and cold exposed rats, but there was an increased hematocrit, increased corpuscular volume, and decreased corpuscular hemoglobin content in rats kept at 6 °C. Hemoglobin, red cells, and plasma specific gravity increased with time in both groups.

Effect of total body water estimates via bioimpedance on bod pod-based three-compartment body fat models

2021 ◽  
Author(s):  
Brett S. Nickerson ◽  
Samantha V. Narvaez ◽  
Mitzy I. Juarez ◽  
Stefan A. Czerwinski
Keyword(s):  
Body Fat ◽  
Total Body Water ◽  
Body Water ◽  
Bod Pod ◽  
Total Body

scholarly journals Effects of a 14-Day Hydration Intervention on Individuals with Habitually Low Fluid Intake

2021 ◽  
Author(s):  
Aaron R. Caldwell ◽  
Megan E. Rosa-Caldwell ◽  
Carson Keeter ◽  
Evan C. Johnson ◽  
François Péronnet ◽  
...  
Keyword(s):  
Body Weight ◽  
Total Body Water ◽  
Fluid Intake ◽  
Urine Volume ◽  
Urine Osmolality ◽  
Body Water ◽  
Control Group ◽  
Intervention Phase ◽  
Total Body ◽  
Experimental Group

<b><i>Background:</i></b> Debate continues over whether or not individuals with low total water intake (TWI) are in a chronic fluid deficit (i.e., low total body water) [<xref ref-type="bibr" rid="ref1">1</xref>]. When women with habitually low TWI (1.6 ± 0.5 L/day) increased their fluid intake (3.5 ± 0.1 L/day) for 4 days 24-h urine osmolality decreased, but there was no change in body weight, a proxy for total body water (TBW) [<xref ref-type="bibr" rid="ref2">2</xref>]. In a small (<i>n</i> = 5) study of adult men, there were no observable changes in TBW, as measured by bioelectrical impedance, after increasing TWI for 4 weeks [<xref ref-type="bibr" rid="ref3">3</xref>]. However, body weight increased and salivary osmolality decreased indicating that the study may have been underpowered to detect changes in TBW. Further, no studies to date have measured changes in blood volume (BV) when TWI is increased. <b><i>Objectives:</i></b> Therefore, the purpose of this study was to identify individuals with habitually low fluid intake and determine if increasing TWI, for 14 days, resulted in changes in TBW or BV. <b><i>Methods:</i></b> In order to identify individuals with low TWI, 889 healthy adults were screened. Participants with a self-reported TWI less than 1.8 L/day (men) or 1.2 L/day (women), and a 24-h urine osmolality greater than 800 mOsm were included in the intervention phase of the study. For the intervention phase, 15 participants were assigned to the experimental group and 8 participants were assigned to the control group. The intervention period lasted for 14 days and consisted of 2 visits to our laboratory: one before the intervention (baseline) and 14 days into the intervention (14-day follow-up). At these visits, BV was measured using a CO-rebreathe procedure and deuterium oxide (D<sub>2</sub>O) was administered to measure TBW. Urine samples were collected immediately prior, and 3–8 h after the D<sub>2</sub>O dose to allow for equilibration. Prior to each visit, participants collected 24-h urine to measure 24-h hydration status. After the baseline visit, the experimental group increased their TWI to 3.7 L for males and 2.7 L for females in order to meet the current Institute of Medicine recommendations for TWI. <b><i>Results:</i></b> Twenty-four-hour urine osmolality decreased (−438.7 ± 362.1 mOsm; <i>p</i> &#x3c; 0.001) and urine volume increased (1,526 ± 869 mL; <i>p</i> &#x3c; 0.001) in the experimental group from baseline, while there were no differences in osmolality (−74.7 ± 572 mOsm; <i>p</i> = 0.45), or urine volume (−32 ± 1,376 mL; <i>p</i> = 0.89) in the control group. However, there were no changes in BV (Fig. <xref ref-type="fig" rid="f01">1</xref>a) or changes in TBW (Fig. <xref ref-type="fig" rid="f01">1</xref>b) in either group. <b><i>Conclusions:</i></b> Increasing fluid intake in individuals with habitually low TWI increases 24-h urine volume and decreases urine osmolality but does not result in changes in TBW or BV. These findings are in agreement with previous work indicating that TWI interventions lasting 3 days [<xref ref-type="bibr" rid="ref2">2</xref>] to 4 weeks [<xref ref-type="bibr" rid="ref3">3</xref>] do not result in changes in TBW. Current evidence would suggest that the benefits of increasing TWI are not related changes in TBW.

Prediction of Total Body Water using Scaled Conjugate Gradient Artificial Neural Network

2020 ◽  
Author(s):  
Marife A. Rosales ◽  
Maria Gemel B. Palconit ◽  
Argel A. Bandala ◽  
Ryan Rhay P. Vicerra ◽  
Elmer P. Dadios ◽  
...  
Keyword(s):  
Neural Network ◽  
Artificial Neural Network ◽  
Conjugate Gradient ◽  
Total Body Water ◽  
Body Water ◽  
Scaled Conjugate Gradient ◽  
Artificial Neural ◽  
Total Body
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