HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text Full Text (PDF) Purchase Article View Shopping Cart Alert me when this article is cited Alert me if a correction is posted Citation Map Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Evans, E. M Articles by Cureton, K. J Search for Related Content PubMed PubMed Citation Articles by Evans, E. M Articles by Cureton, K. J Agricola Articles by Evans, E. M Articles by Cureton, K. J

Body-composition changes with diet and exercise in obese women: a comparison of estimates from clinical methods and a 4-component model^1,2,3

¹ From the Departments of Exercise Science and Foods and Nutrition, The University of Georgia, Athens.

Background: Most methods available to clinicians for estimating body-composition changes have been validated against estimates from densitometry, based on a 2-component (fat mass and fat-free mass) model.

Objective: Estimates of changes in percentage body fat (%BF) from dual-energy X-ray absorptiometry (DXA), skinfold thicknesses (SFTs), bioelectrical impedance analysis (BIA), and body mass index (BMI; in kg/m²) were compared with estimates from a 4-component (fat, water, mineral, and protein) model (%BF_d,w,m), a more accurate method.

Design: Determinations of body density from hydrostatic weighing, body water from deuterium dilution, bone mineral and %BF from whole-body DXA, resistance from BIA, and anthropometric measures were made in 27 obese women (BMI: 31.1 ± 4.9) assigned to 1 of 3 groups: control (C; n = 9), diet only (DO; n = 9), or diet plus aerobic exercise (DE; n = 9).

Results: After the 16-wk intervention, changes in body mass (BM) averaged 0.5 ± 2.0, -7.2 ± 7.4, and -4.0 ± 3.3 kg and changes in %BF_d,w,m averaged 2.1 ± 1.0%, -1.2 ± 1.4%, and -2.4 ± 1.6% in the C, DO, and DE groups, respectively. Compared with changes in %BF_d,w,m, the errors (SD of bias) for estimates of changes in %BF by DXA, BIA, SFTs, and BMI were similar (range: ±2.0–2.4% of BM). BIA, SFTs, and BMI provided unbiased estimates of decreases in %BF_d,w,m, but DXA overestimated decreases in %BF in the DO and DE groups.

Conclusions: DXA, BIA, SFTs, and BMI are comparably accurate for evaluating body-composition changes induced by diet and exercise interventions; however, small changes in %BF may not be accurately detected by these clinical methods.

Key Words: Bioelectrical impedance analysis • BIA • body mass index • dual-energy X-ray absorptiometry • DXA • multicomponent models • anthropometric measures • skinfold thickness • weight loss • body composition • exercise • humans

This article has been cited by other articles:

				S. K. Das, S. B. Roberts, J. J. Kehayias, J. Wang, L. K. G. Hsu, S. A. Shikora, E. Saltzman, and M. A McCrory Body composition assessment in extreme obesity and after massive weight loss induced by gastric bypass surgery Am J Physiol Endocrinol Metab, June 1, 2003; 284(6): E1080 - E1088. [Abstract] [Full Text] [PDF]

				L. A. Powell, D. C. Nieman, C. Melby, K. Cureton, D. Schmidt, E. T. Howley, J. O. Hill, J. R. Mault, H. Alexander, and D. J. Stewart Assessment of Body Composition Change in a Community-Based Weight Management Program J. Am. Coll. Nutr., February 1, 2001; 20(1): 26 - 31. [Abstract] [Full Text] [PDF]

				P Tothill, W J Hannan, and S Wilkinson Comparisons between a pencil beam and two fan beam dual energy X-ray absorptiometers used for measuring total body bone and soft tissue Br. J. Radiol., February 1, 2001; 74(878): 166 - 176. [Abstract] [Full Text] [PDF]