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Dale A. Schoeller - One of the best experts on this subject based on the ideXlab platform.

  • adult energy requirements predicted from Doubly Labeled Water
    International Journal of Obesity, 2018
    Co-Authors: Andrew Plucker, Dale A. Schoeller, Steven B Heymsfield, Diana M Thomas, Nick Broskey, Corby K Martin, Robin P Shook, James A Levine, Leanne Redman
    Abstract:

    Estimating energy requirements forms an integral part of developing diet and activity interventions. Current estimates often rely on a product of physical activity level (PAL) and a resting metabolic rate (RMR) prediction. PAL estimates, however, typically depend on subjective self-reported activity or a clinician’s best guess. Energy-requirement models that do not depend on an input of PAL may provide an attractive alternative. Total daily energy expenditure (TEE) measured by Doubly Labeled Water (DLW) and a metabolic chamber from 119 subjects obtained from a database of pre-intervention measurements measured at Pennington Biomedical Research Center were used to develop a metabolic ward and free-living models that predict energy requirements. Graded models, including different combinations of input variables consisting of age, height, weight, waist circumference, body composition, and the resting metabolic rate were developed. The newly developed models were validated and compared to three independent databases. Sixty-four different linear and nonlinear regression models were developed. The adjusted R2 for models predicting free-living energy requirements ranged from 0.65 with covariates of age, height, and weight to 0.74 in models that included body composition and RMR. Independent validation R2 between actual and predicted TEE varied greatly across studies and between genders with higher coefficients of determination, lower bias, slopes closer to 1, and intercepts closer to zero, associated with inclusion of body composition and RMR covariates. The models were programmed into a user-friendly web-based app available at: http://www.pbrc.edu/research-and-faculty/calculators/energy-requirements/ (Video Demo for Reviewers at: https://www.youtube.com/watch?v=5UKjJeQdODQ ) Energy-requirement equations that do not require knowledge of activity levels and include all available input variables can provide more accurate baseline estimates. The models are clinically accessible through the web-based application.

  • dilution space ratio of 2h and 18o of Doubly Labeled Water method in humans
    Journal of Applied Physiology, 2016
    Co-Authors: Hiroyuki Sagayama, Yosuke Yamada, Natalie Racine, Timothy Shriver, Dale A. Schoeller
    Abstract:

    The Doubly Labeled Water method is a precise method for measuring energy expenditure in free-living individuals. Its accuracy, however, is dependent on the ratio the relative dilution spaces of the...

  • validity of Doubly Labeled Water in obese subjects questioning the validity of any technique requires an indisputable accuracy of the reference method
    American Journal of Physiology-endocrinology and Metabolism, 2013
    Co-Authors: Stéphane Blanc, Yosuke Yamada, Timothy Shriver, Naoyuki Ebine, Yuichiro Nishida, Kazutoshi Nishijima, Dale A. Schoeller
    Abstract:

    to the editor: In a recent article, Guidotti et al. ([5][1]) reported that the nutritional and body adiposity status affects the dilution space ratio (Nd/No) between deuterium (2H) and 18O and validity of CO2 production (rCO2) by the Doubly Labeled Water (DLW) method in mice. Their data disagree

  • Doubly Labeled Water analysis using cavity ring down spectroscopy
    Rapid Communications in Mass Spectrometry, 2011
    Co-Authors: Thomas Thorsen, Timothy Shriver, Natalie Racine, Bruce A Richman, Dale A. Schoeller
    Abstract:

    The Doubly Labeled Water method provides an objective and accurate measure of total energy expenditure in free-living subjects and is considered the gold-standard method for this measurement. Its use, however, is limited by the need to employ isotope ratio mass spectrometry (IRMS) to obtain the high-precision isotopic abundance analyses needed to optimize the dose of expensive 18O-Labeled Water. Recently, cavity-ring down spectroscopy (CRDS) instruments have become commercially available and may serve as a less expensive alternative to IRMS. We compared the precision and accuracy of CRDS with those of IRMS for the measurement of total energy expenditure from urine specimens in 14 human subjects. The relative accuracy and precision (SD) for total body Water was 0.5 ± 1% and for total energy expenditure was 0.5 ± 6%. The CRDS instrument displayed a memory between successive specimens of 5% for 18O and 9% for 2H. The memory necessitated carefully ordering of specimens to reduce isotopic disparity, performance of several injections of each specimen to condition the analyzer, and use of a mathematical memory correction on subsequent injections. These limited the specimen throughput to about one urine specimen per hour. CRDS provided accuracy and precision for isotope abundance measurements of urine that were comparable with those of IRMS. The memory problems were easily recognized by our experienced laboratory staff, but future efforts should be aimed at reducing the memory of the CRDS so that it would be less likely to result in poor reproducibility in laboratories using Doubly Labeled Water for the first time. Copyright © 2010 John Wiley & Sons, Ltd.

  • insights into energy balance from Doubly Labeled Water
    International Journal of Obesity, 2008
    Co-Authors: Dale A. Schoeller
    Abstract:

    Obesity is defined as the excess storage of energy in the form of fat that results from imbalances between energy intake and expenditure. The study of the components of energy balance has undergone a significant advancement with the application of the Doubly Labeled Water (DLW) method to the measurement of human energy expenditure. This manuscript includes a selective review of the studies that have utilized the Doubly Labeled method as it applies to the study of human obesity. Although generally now accepted, one of the major surprises from the early applications of DLW was that obese individuals have higher energy expenditures than lean controls. Moreover, weight gain, even in the already obese, is associated with an increase in energy expenditure as weight is one of the strongest predictors of total energy expenditure. Similarly, studies of weight loss treatment show a decrease in energy expenditure due to weight loss and due to adaptive changes in energetic efficiency, but these changes do not account for the common cessation of weight loss observed after 12–26 weeks of restriction. The accumulating data from the application of the DLW method suggest a need to place greater emphasis on mechanisms that lead to a mismatch between energy intake and expenditure rather than a continuing emphasis on energy intake or energy expenditure alone.

Timothy Shriver - One of the best experts on this subject based on the ideXlab platform.

  • dilution space ratio of 2h and 18o of Doubly Labeled Water method in humans
    Journal of Applied Physiology, 2016
    Co-Authors: Hiroyuki Sagayama, Yosuke Yamada, Natalie Racine, Timothy Shriver, Dale A. Schoeller
    Abstract:

    The Doubly Labeled Water method is a precise method for measuring energy expenditure in free-living individuals. Its accuracy, however, is dependent on the ratio the relative dilution spaces of the...

  • validity of Doubly Labeled Water in obese subjects questioning the validity of any technique requires an indisputable accuracy of the reference method
    American Journal of Physiology-endocrinology and Metabolism, 2013
    Co-Authors: Stéphane Blanc, Yosuke Yamada, Timothy Shriver, Naoyuki Ebine, Yuichiro Nishida, Kazutoshi Nishijima, Dale A. Schoeller
    Abstract:

    to the editor: In a recent article, Guidotti et al. ([5][1]) reported that the nutritional and body adiposity status affects the dilution space ratio (Nd/No) between deuterium (2H) and 18O and validity of CO2 production (rCO2) by the Doubly Labeled Water (DLW) method in mice. Their data disagree

  • Doubly Labeled Water analysis using cavity ring down spectroscopy
    Rapid Communications in Mass Spectrometry, 2011
    Co-Authors: Thomas Thorsen, Timothy Shriver, Natalie Racine, Bruce A Richman, Dale A. Schoeller
    Abstract:

    The Doubly Labeled Water method provides an objective and accurate measure of total energy expenditure in free-living subjects and is considered the gold-standard method for this measurement. Its use, however, is limited by the need to employ isotope ratio mass spectrometry (IRMS) to obtain the high-precision isotopic abundance analyses needed to optimize the dose of expensive 18O-Labeled Water. Recently, cavity-ring down spectroscopy (CRDS) instruments have become commercially available and may serve as a less expensive alternative to IRMS. We compared the precision and accuracy of CRDS with those of IRMS for the measurement of total energy expenditure from urine specimens in 14 human subjects. The relative accuracy and precision (SD) for total body Water was 0.5 ± 1% and for total energy expenditure was 0.5 ± 6%. The CRDS instrument displayed a memory between successive specimens of 5% for 18O and 9% for 2H. The memory necessitated carefully ordering of specimens to reduce isotopic disparity, performance of several injections of each specimen to condition the analyzer, and use of a mathematical memory correction on subsequent injections. These limited the specimen throughput to about one urine specimen per hour. CRDS provided accuracy and precision for isotope abundance measurements of urine that were comparable with those of IRMS. The memory problems were easily recognized by our experienced laboratory staff, but future efforts should be aimed at reducing the memory of the CRDS so that it would be less likely to result in poor reproducibility in laboratories using Doubly Labeled Water for the first time. Copyright © 2010 John Wiley & Sons, Ltd.

  • use of an automated chromium reduction system for hydrogen isotope ratio analysis of physiological fluids applied to Doubly Labeled Water analysis
    Journal of Mass Spectrometry, 2000
    Co-Authors: Dale A. Schoeller, Timothy Shriver, Amanda S Colligan, Hairigh Avak, Cynthia Bartokolson
    Abstract:

    The Doubly Labeled Water method is commonly used to measure total energy expenditure in free-living subjects. The method, however, requires accurate and precise deuterium abundance determinations, which can be laborious. The aim of this study was to evaluate a fully automated, high-throughput, chromium reduction technique for the measurement of deuterium abundances in physiological fluids. The chromium technique was compared with an off-line zinc bomb reduction technique and also subjected to test–retest analysis. Analysis of international Water standards demonstrated that the chromium technique was accurate and had a within-day precision of <1‰. Addition of organic matter to Water samples demonstrated that the technique was sensitive to interference at levels between 2 and 5 g l−1. Physiological samples could be analyzed without this interference, plasma by 10000 Da exclusion filtration, saliva by sedimentation and urine by decolorizing with carbon black.. Chromium reduction of urine specimens from Doubly Labeled Water studies indicated no bias relative to zinc reduction with a mean difference in calculated energy expenditure of −0.2 ± 3.9%. Blinded reanalysis of urine specimens from a second Doubly Labeled Water study demonstrated a test–retest coefficient of variation of 4%. The chromium reduction method was found to be a rapid, accurate and precise method for the analysis of urine specimens from Doubly Labeled Water. Copyright © 2000 John Wiley & Sons, Ltd.

  • Use of an automated chromium reduction system for hydrogen isotope ratio analysis of physiological fluids applied to Doubly Labeled Water analysis
    Journal of Mass Spectrometry, 2000
    Co-Authors: Dale A. Schoeller, Timothy Shriver, Amanda S Colligan, Hairigh Avak, Cynthia Bartok-olson
    Abstract:

    The Doubly Labeled Water method is commonly used to measure total energy expenditure in free-living subjects. The method, however, requires accurate and precise deuterium abundance determinations, which can be laborious. The aim of this study was to evaluate a fully automated, high-throughput, chromium reduction technique for the measurement of deuterium abundances in physiological fluids. The chromium technique was compared with an off-line zinc bomb reduction technique and also subjected to test–retest analysis. Analysis of international Water standards demonstrated that the chromium technique was accurate and had a within-day precision of

Klaas R Westerterp - One of the best experts on this subject based on the ideXlab platform.

  • inaccuracies in food and physical activity diaries of obese subjects complementary evidence from Doubly Labeled Water and co twin assessments
    International Journal of Obesity, 2010
    Co-Authors: Klaas R Westerterp, Kirsi H Pietilainen, Maarit Korkeila, Leonie H Bogl, Hannele Ykijarvinen, Jaakko Kaprio, Aila Rissanen
    Abstract:

    Inaccuracies in food and physical activity diaries of obese subjects: complementary evidence from Doubly Labeled Water and co-twin assessments

  • assessment of the physical activity level with two questions validation with Doubly Labeled Water
    International Journal of Obesity, 2008
    Co-Authors: Gunnar Johansson, Klaas R Westerterp
    Abstract:

    Assessment of the physical activity level with two questions: validation with Doubly Labeled Water

  • physical activity assessment with accelerometers an evaluation against Doubly Labeled Water
    Obesity, 2007
    Co-Authors: Guy Plasqui, Klaas R Westerterp
    Abstract:

    This review focuses on the ability of different accelerometers to assess daily physical activity as compared with the Doubly Labeled Water (DLW) technique, which is considered the gold standard for measuring energy expenditure under free-living conditions. The PubMed Central database (U.S. NIH free digital archive of biomedical and life sciences journal literature) was searched using the following key words: Doubly or double Labeled or Labeled Water in combination with accelerometer, accelerometry, motion sensor, or activity monitor. In total, 41 articles were identified, and screening the articles’ references resulted in one extra article. Of these, 28 contained sufficient and new data. Eight different accelerometers were identified: 3 uniaxial (the Lifecorder, the Caltrac, and the CSA/MTI/Actigraph), one biaxial (the Actiwatch AW16), 2 triaxial (the Tritrac-R3D and the Tracmor), one device based on two position sensors and two motion sensors (ActiReg), and the foot-ground contact pedometer. Many studies showed poor results. Only a few mentioned partial correlations for accelerometer counts or the increase in R2 caused by the accelerometer. The correlation between the two methods was often driven by subject characteristics such as body weight. In addition, standard errors or limits of agreement were often large or not presented. The CSA/MTI/Actigraph and the Tracmor were the two most extensively validated accelerometers. The best results were found for the Tracmor; however, this accelerometer is not yet commercially available. Of those commercially available, only the CSA/MTI/Actigraph has been proven to correlate reasonably with DLW-derived energy expenditure.

  • Physical activity level measured by Doubly Labeled Water and accelerometry in children
    European Journal of Applied Physiology, 2003
    Co-Authors: Marije B. Hoos, Guy Plasqui, Willem-jan M. Gerver, Klaas R Westerterp
    Abstract:

    The present study investigated the use of a tri-axial accelerometer, Tracmor2, for the measurement of physical activity in children. Eleven children [age 6.9 (2.2) years, body mass 19.5 (5.3) kg and height 112.3 (14.4) cm] were studied. Total daily energy expenditure (TDEE) was measured using the Doubly Labeled Water method over a 2-week period. In addition, basal metabolic rate (BMR) was determined by the ventilated hood system. Physical activity level (PAL) was defined as TDEE/BMR. Tracmor2 was worn during the same 2-week period throughout waking hours after which average counts per day were calculated. The average counts per day were shown to be highly correlated to PAL values measured by Doubly Labeled Water: PAL = 1.156×10−5×Tracmor2 average counts day−1 + 0.978 (r=0.79, P

  • physical activity level measured by Doubly Labeled Water and accelerometry in children
    European Journal of Applied Physiology, 2003
    Co-Authors: Marije B. Hoos, Guy Plasqui, Willem-jan M. Gerver, Klaas R Westerterp
    Abstract:

    The present study investigated the use of a tri-axial accelerometer, Tracmor2, for the measurement of physical activity in children. Eleven children [age 6.9 (2.2) years, body mass 19.5 (5.3) kg and height 112.3 (14.4) cm] were studied. Total daily energy expenditure (TDEE) was measured using the Doubly Labeled Water method over a 2-week period. In addition, basal metabolic rate (BMR) was determined by the ventilated hood system. Physical activity level (PAL) was defined as TDEE/BMR. Tracmor2 was worn during the same 2-week period throughout waking hours after which average counts per day were calculated. The average counts per day were shown to be highly correlated to PAL values measured by Doubly Labeled Water: PAL = 1.156×10−5×Tracmor2 average counts day−1 + 0.978 (r=0.79, P<0.01). In conclusion, Tracmor2 is a valid instrument to measure physical activity in children under free-living conditions.

Michael I. Goran - One of the best experts on this subject based on the ideXlab platform.

  • comparison of multiple pass 24 hour recall estimates of energy intake with total energy expenditure determined by the Doubly Labeled Water method in young children
    Journal of The American Dietetic Association, 1996
    Co-Authors: Rachel K. Johnson, Patricia A Driscoll, Michael I. Goran
    Abstract:

    Abstract Objective This study determined the accuracy of the multiple-pass 24-hour recall method for estimating energy intake in young children by comparing it with measurements of total energy expenditure made using the Doubly Labeled Water method. Design Three multiple-pass 24-hour recalls were obtained over a 14-day period to estimate mean energy intake. Total energy expenditure was measured over the same 14-day period under free-living conditions using the Doubly Labeled Water technique. Subjects/setting Twenty-four children between the ages of 4 and 7 years were tested at the General Clinical Research Center/Sims Obesity Nutrition Research Center at the University of Vermont. Statistical analysis t Tests, paired t tests, Pearson product-moment correlation coefficients, pairwise comparison to show relative bias and limits of agreement, and regression analysis were used to test the relationships among study variables. Results No difference was found between 3-day mean energy intake and total energy expenditure for the group ( t =2.07, P =.65). The correlation between individual measures of energy intake and total energy expenditure was not statistically significant ( r =.25, P =.24). Conclusions Data from 3 days of multiple-pass 24-hour recalls were sufficient to make valid group estimates of energy intake. The method was not precise for individual measurements of energy intake. J Am Diet Assoc. 1996; 96:1140-1144.

  • Experimental reliability of the Doubly Labeled Water technique.
    The American journal of physiology, 1994
    Co-Authors: Michael I. Goran, Eric T. Poehlman, Elliot Danforth
    Abstract:

    The experimental reliability of measuring CO2 production rates (rCO2) with the Doubly Labeled Water (DLW) technique was assessed in five young healthy men (23 (DLW) technique was assessed in five young healthy men (23 +/- 4 yr; 66.1 +/- 4.6 kg). To minimize the confounding effects of fluctuations in physical activity and eating patterns on variation in energy expenditure, the subjects lived under sedentary living conditions by confinement to their own room at a Clinical Research Center and were maintained on a fixed and known level of energy intake. rCO2 was determined in duplicate over two identical 9-day study periods after separate loading doses of deuterium and oxygen-18. Turnover rates were determined from multipoint sampling to reduce error from analytical uncertainty. Dilution spaces were determined by both the intercept and plateau methods. The average experimental variation for rCO2 estimates was approximately +/- 8.5% and was not significantly different among three published calculation models that differ in their assumptions regarding the relationship between the dilution spaces of deuterium and oxygen-18. The experimental reliability of +/- 8.5% exceeds theoretical values generated from calculations based on propagation of error from analytical uncertainty. Between subjects, the experimental variation ranged from 1 to 21%, and the half-width of the 95% confidence interval for the precision of rCO2 estimates was high (+/- 12 mol/day) relative to the mean reported value of approximately 16 mol/day.(ABSTRACT TRUNCATED AT 250 WORDS)

  • Experimental reliability of the Doubly Labeled Water technique.
    American Journal of Physiology-endocrinology and Metabolism, 1994
    Co-Authors: Michael I. Goran, Eric T. Poehlman, Elliot Danforth
    Abstract:

    The experimental reliability of measuring CO2 production rates (rCO2) with the Doubly Labeled Water (DLW) technique was assessed in five young healthy men (23 (DLW) technique was assessed in five y...

  • Application of the Doubly Labeled Water Technique for Studying Total Energy Expenditure in Young Children: A Review
    Pediatric Exercise Science, 1994
    Co-Authors: Michael I. Goran
    Abstract:

    The Doubly Labeled Water technique represents an unobtrusive and noninvasive means to measure total daily energy expenditure in free-living human subjects who are unaware that energy expenditure is being measured. When combined with measurement of resting energy expenditure, the Doubly Labeled Water technique can also be used to estimate energy expenditure related to physical activity. The relatively recent availability of the Doubly Labeled Water technique in humans has led to several advances in the fundamental understanding of whole body energy metabolism in several important areas. The purpose of this paper is to review the areas in which the Doubly Labeled Water technique has specifically advanced our understanding of whole-body energy metabolism in young children.

John R. Speakman - One of the best experts on this subject based on the ideXlab platform.

  • validation of the Doubly Labeled Water method using off axis integrated cavity output spectroscopy and isotope ratio mass spectrometry
    American Journal of Physiology-endocrinology and Metabolism, 2018
    Co-Authors: Edward L Melanson, John R. Speakman, Guy Plasqui, Tracy Swibas, Wendy M Kohrt, Vicki A Catenacci, Seth A Creasy, Loek Wouters, Elena S F Berman
    Abstract:

    When the Doubly Labeled Water (DLW) method is used to measure total daily energy expenditure (TDEE), isotope measurements are typically performed using isotope ratio mass spectrometry (IRMS). New t...

  • The history and theory of the Doubly Labeled Water technique.
    The American Journal of Clinical Nutrition, 1998
    Co-Authors: John R. Speakman
    Abstract:

    Scientists have been measuring energy expenditure by using gas exchange for the past 200 y. This technique is based on earlier work in the 1660s. Gas exchange in respirometers provides accurate and repeatable measures of resting metabolic rate. However, it is impossible to duplicate in a respirometry chamber the diversity of human behaviors that influence energy expenditure. The Doubly Labeled Water technique is an isotope-based method that measures the energy expenditure of unencumbered subjects from the divergence in enrichments of 2 isotopic labels in body Water—1 of hydrogen and 1 of oxygen. The method was invented in the 1950s and applied to small animals only until the early 1980s, mostly because of the expense. Since 1982, when the first study in humans was published, its use has expanded enormously. Although there is some debate over the precise calculation protocols that should be used, the differences between alternative calculations result in relatively minor effects on total energy expenditure estimates (

  • the history and theory of the Doubly Labeled Water technique
    The American Journal of Clinical Nutrition, 1998
    Co-Authors: John R. Speakman
    Abstract:

    Scientists have been measuring energy expenditure by using gas exchange for the past 200 y. This technique is based on earlier work in the 1660s. Gas exchange in respirometers provides accurate and repeatable measures of resting metabolic rate. However, it is impossible to duplicate in a respirometry chamber the diversity of human behaviors that influence energy expenditure. The Doubly Labeled Water technique is an isotope-based method that measures the energy expenditure of unencumbered subjects from the divergence in enrichments of 2 isotopic labels in body Water—1 of hydrogen and 1 of oxygen. The method was invented in the 1950s and applied to small animals only until the early 1980s, mostly because of the expense. Since 1982, when the first study in humans was published, its use has expanded enormously. Although there is some debate over the precise calculation protocols that should be used, the differences between alternative calculations result in relatively minor effects on total energy expenditure estimates (<6%). Validation studies show that for groups of subjects the method works well, but that precision is still relatively poor (8-9%) and consequently the method is not yet sufficiently refined to provide estimates of individual energy expenditures. Am J Clin Nutr 1998;

  • revised equations for calculating co2 production from Doubly Labeled Water in humans
    American Journal of Physiology-endocrinology and Metabolism, 1993
    Co-Authors: John R. Speakman, K S Nair, M I Goran
    Abstract:

    The Schoeller model for calculating rate of CO2 production (rCO2) from Doubly Labeled Water (DLW) relies on the assumption that deuterium and oxygen-18 overestimate body Water by 4 and 1%, respectively. However, the deuterium-to-oxygen-18 dilution space ratio (DSR) varies considerably, and it is unknown whether this is due to analytical or biological sources. From 161 published values in adult humans, we derived a mean DSR of 1.0427 +/- 0.0218. Propagation of error suggests that analytical uncertainty accounts for 20-50% of the observed variation in the DSR, whereas reliability testing in vivo and in vitro demonstrate that 70-100% of observed interindividual variation in the DSR can be attributed to analytical uncertainty. The discrepancy between propagated error and experimental reliability suggest that it is unwise to rely on propagation of error when evaluating sources of error in DLW. The new constant of 1.0427 was used to revise existing equations for calculating rCO2 from DLW. Compared with the existing equation, the revised equation improved the accuracy (-0.38 vs. +10.3%) and the precision (9.3 vs 10.7%) of rCO2 calculations in previously published validation studies. We conclude that 1) variation in the oxygen-18-to-deuterium DSR is primarily influenced by analytical noise and warrants use of a fixed ratio, 2) existing equations should be revised because the original DSR may have been underestimated, and 3) the modified equations improve the accuracy and precision of rCO2 calculated from DLW.