title: Air displacement plethysmography for estimating body composition changes with weight loss in middle-aged Japanese men.
abstract: OBJECTIVE
  To examine the degree to which air displacement plethysmography (ADP) can track body composition changes in response to weight loss in obese Japanese men.
  
  
  METHODS
  50 men, aged 30-65 years with a mean BMI of 30 kg/m(2), were included in a 3-month weight loss program. Percentage of fat mass (%FM) was determined by dual energy X-ray absorptiometry (DXA) and ADP at baseline and month 3.
  
  
  RESULTS
  With 6.2 ± 4.3 kg of weight loss, %FM, as determined by DXA and ADP, significantly decreased by 3.9 ± 2.9% and 3.9 ± 3.3% respectively. There was no mean difference for change (Δ) in %FM between the two methods. DXA-derived Δ%FM significantly correlated with Δ%FM determined by ADP (R(2) = 0.48, p < 0.01). Furthermore, the Bland-Altman plots demonstrated no systematic bias for Δ%FM (r = -0.20, p = 0.17). However, %FM by ADP (r = 0.42) at baseline and Δ%FM by ADP (r = -0.54) were significantly correlated to the differences between Δ%FM by DXA and ADP.
  
  
  CONCLUSIONS
  These results suggest that ADP is comparably accurate for evaluating Δ%FM when compared with DXA, although there were proportional biases.
authors.affiliation: Graduate School of Comprehensive Human Sciences, University of Tsukuba, Ibaraki, Tokyo, Japan. h-sasai@umin.ac.jp
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Sasai
authors.forename: Yoshio
authors.initials: Y
authors.lastname: Nakata
authors.forename: Miyuki
authors.initials: M
authors.lastname: Nemoto
authors.forename: Kazunori
authors.initials: K
authors.lastname: Ohkawara
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Ohkubo
authors.forename: Tomoaki
authors.initials: T
authors.lastname: Matsuo
authors.forename: Maeng-Kyu
authors.initials: MK
authors.lastname: Kim
authors.forename: Yasutomi
authors.initials: Y
authors.lastname: Katayama
authors.forename: Kiyoji
authors.initials: K
authors.lastname: Tanaka
mesh_terms: D015502:Absorptiometry, Photon; D050154:Adiposity / Q000208:ethnology; D000328:Adult; D000368:Aged; D044466:Asian People; D001823:Body Composition; D015992:Body Mass Index; D006801:Humans; D007564:Japan; D008297:Male; D008875:Middle Aged; D009765:Obesity / Q000208:ethnology / Q000503:physiopathology / Q000628:therapy*; D010991:Plethysmography; D011237:Predictive Value of Tests; D013997:Time Factors; D016896:Treatment Outcome; D015431:Weight Loss / Q000208:ethnology*