A comparative study of different means of assessing long-term energy expenditure in humans. Rosenbaum, Michael, Eric Ravussin, Dwight E. Matthews, Chuck Gilker, Robert Ferraro, Steven B. Heymsfield, Jules Hirsch, and Rudolph L. Leibel. Laboratory of Human Behavior and Metabolism, Rockefeller University, New York, NY (M.R., J.H. and R.L.L.); The New York Hospital/Cornell University Medical Center, New York, NY (D.E.M. and C.G.); Clinical Diabetes and Nutrition Section, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Phoenix, AZ (E.R. and R.F.); Obesity Research Center, Dept. of Medicine, St. Luke's-Roosevelt Hospital Center, New York, NY (S.B.H.).
APStracts 2:0246R, 1995.
We compared 3 independent techniques for measurement of total energy expenditure (TEE) in human subjects: 1. Weight- maintaining energy intake (dietTEE); 2. 24 hour chamber calorimetry (chamberTEE); and 3. Differential elimination rates 2H2O and H218O (isotopeTEE). Twenty three healthy adult in-patients [19 never obese (NO), 2 obese (OB) and 2 formerly-obese (RO); 9 female, 14 male] ingested a liquid formula diet (40% of calories as fat, 45% CHO, 15% protein), the volume of which was adjusted until body weight was stable for at least 14 days. Body composition was then determined by hydrodensitometry, isotope dilution, and dual photon beam absorptiometry (DXA). The thermic effect of feeding (TEF) and resting energy expenditure (REE, measured before arising (dietREE) and after arising (chamberREE)) were determined by indirect calorimetry. Non -resting energy expenditure (NREE) was calculated as NREE = TEE - (REE + TEF). Subjects then gained or lost 10% of their body weight and were restudied as described above.

Received 23 January 1995; accepted in final form 23 August 1995.
APS Manuscript Number R57-5.
Article publication pending Am. J. Physiol. (Regulatory Integrative
Comp. Physiology).
ISSN 1080-4757 Copyright 1995 The American Physiological Society.
Published in APStracts on 23 September 1995.