title: Body composition in male elite athletes, comparison of bioelectrical impedance spectroscopy with dual energy X-ray absorptiometry.
abstract: BACKGROUND
  The aim of this study was to compare body composition results from bioelectrical spectroscopy (BIS) with results from dual energy X-ray absorptiometry (DXA) in a population of male elite athletes. Body composition was assessed using DXA (Lunar Prodigy, GE Lunar Corp., Madison, USA) and BIS (Hydra 4200, Xitron Technologies Inc, San Diego, California, USA) at the same occasion. Agreement between methods was assessed using paired t-tests and agreement-plots.
  
  
  RESULTS
  Thirty-three male elite athletes (soccer and ice hockey) were included in the study. The results showed that BIS underestimates the proportion of fat mass by 4.6% points in the ice hockey players. In soccer players the BIS resulted in a lower mean fat mass by 1.1% points. Agreement between the methods at the individual level was highly variable.
  
  
  CONCLUSIONS
  Body composition results assessed by BIS in elite athletes should be interpreted with caution, especially in individual subjects. BIS may present values of fat mass that is either higher or lower than fat mass assessed by DXA, independent of true fat content of the individual.
authors.affiliation: Department of Clinical Nutrition, Sahlgrenska Academy, University of Gothenburg, Sweden. ulla.svantesson@fhs.gu.se
authors.forename: Ulla
authors.initials: U
authors.lastname: Svantesson
authors.forename: Martina
authors.initials: M
authors.lastname: Zander
authors.forename: Sofia
authors.initials: S
authors.lastname: Klingberg
authors.forename: Frode
authors.initials: F
authors.lastname: Slinde
mesh_terms: D015502:Absorptiometry, Photon; D000273:Adipose Tissue / Q000033:anatomy & histology; D000328:Adult; D000886:Anthropometry / Q000379:methods; D001823:Body Composition; D015992:Body Mass Index; D001835:Body Weight; D017097:Electric Impedance; D006688:Hockey; D006801:Humans; D008297:Male; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D012916:Soccer