Validation of the BOD POD with hydrostatic weighing: Influence of body clothingin

Abstract

OBJECTIVE: Whole body air-displacement plethysmography (BOD POD), a new body composition technique, was validated against hydrodensitometry (UWW) in 67 women wearing a one-piece swimsuit (OP) who represent a wide range of body fatness and age. Additionally, the effect of trapped isothermic air in clothing while in the BOD POD was examined by comparing different clothing schemes (a one-piece swimsuit (OP), two-piece swimsuit (TP), a hospital gown (HG), and a hospital gown previously included in a volume calibration (GC)) in a subset of 25 women. DESIGN: Cross-sectional data analysis. SUBJECTS: 67 healthy Caucasian females. MEASUREMENTS: Body density gacm 3 (Db) by BOD POD and UWW. RESULTS: In 67 females UWW Db (1.030 AE 0.020 gacm 3 ) was higher (P`0.01) than BOD POD Db (1.028 AE 0.020 gacm 3 ). This is a difference of 1.0% fat. The R 2 was 0.94, SEE was 0.005 gacm 3 and the regression between Db by UWW and BOD POB did not signi®cantly deviate from the line of identity. In the subset group of 25 subjects, OP Db (1.040 AE 0.014 gacm 3 ) and TP Db (1.040 AE 0.014 gacm 3 ) were signi®cantly lower (P`0.01) than UWW Db (1.044 AE 0.014 gacm 3 ) or a difference of 1.9% fat. The R 2 was 0.86 and the SEE was 0.005 gacm 3 and the regression between Db by UWW and both OP and TP did not signi®cantly deviate from the line of identity. HG Db (1.056 AE 0.016 gacm 3 ) and GC Db (1.037 AE 0.016 gacm 3 ) were signi®cantly different (P`0.01) from UWW Db (1.044 AE 0.014 gacm 3 ). This difference in density translates to a difference of 5.5% and 3.2% fat respectively. The regression between Db by UWW and both HG and GC signi®cantly deviated from the line of identity. CONCLUSION: This study supports the use of the BOD POD as a substitute for UWW. However, caution should be made in using the BOD POD if subjects are clothed in anything other than a tight ®tting swimsuit.

Association Between Adiposity and Lean Mass With Long‐Term Cardiovascular Events in Patients With Coronary Artery Disease: No Paradox

“…Body volume is obtained from chamber gas pressure difference under isothermal conditions, applying Boyle's and Poisson's laws. The principles of densitometry are then applied, where body density is calculated as total body mass in kilograms (kg)/body volume (L) 7, 13, 14, 15. Then, body density is used in the Siri's formula to derive BF mass (BF mass=[4.95/body density−4.50]×100) 16.…”

Changes in thoracic gas volume with air-displacement plethysmography after a weight loss program in overweight and obese women

“…Furthermore, test-retest reliability, between-day variability, within-subject variability and between-instrument variability appear to be good to excellent (Fields et al, 2002;Ball, 2005;Going, 2005). Other studies have also assessed the importance of selected methodological issues associated with ADP such as the effects of clothing, hair and skin surface area to measure body volume (Vb) with adequate accuracy (Fields et al, 2000(Fields et al, , 2002.…”

Body composition techniques and the four-compartment model in children

“…Total body density was also evaluated with the BOD POD body composition system (version 1.69, Life Measurement Instruments, Concord, CA) as previously described (4). Briefly, the testing procedure involves several steps.…”