title: Dual-energy X-ray absorptiometry measured regional body composition least significant change: effect of region of interest and gender in athletes.
abstract: Dual-energy X-ray absorptiometry (DXA) is widely used to evaluate body composition in athletes. Knowledge of measurement precision is essential for monitoring body composition changes over time. This study begins characterizing DXA body composition precision in 60 (30 males and 30 females) Division 1 athletes focusing on gender, regional, and tissue type differences. Two total body scans with repositioning between were performed on the same day. Least significant change (LSC) for the root-mean-square deviation (LSCRMSD) and the percent coefficient of variation (LSC%CV) for total, lean, and fat mass was calculated for 6 regions of interest. The effect of gender, region, tissue type, and mass on the standard deviation (SD) and percent coefficient of variation (%CV) between the 2 scans was evaluated using repeated measures regression analysis. Statistically significant effects of gender, region, tissue type, and mass on SD and %CV were noted. To generalize, a nonlinear positive relationship between LSCRMSD and mass and a nonlinear negative relationship between LSC%CV and mass were observed. In conclusion, DXA body composition LSC varies among genders, regions, tissues, and mass. As such, when evaluating serial body composition in athletes, especially if assessing regional change, knowledge of precision in individuals of similar body size and gender to the population of interest is needed.
authors: Osteoporosis Clinical Research Program, University of Wisconsin-Madison, Madison, WI, USA.
authors: Bjoern
authors: B
authors: Buehring
authors: Osteoporosis Clinical Research Program, University of Wisconsin-Madison, Madison, WI, USA.
authors: Diane
authors: D
authors: Krueger
authors: Osteoporosis Clinical Research Program, University of Wisconsin-Madison, Madison, WI, USA.
authors: Jessie
authors: J
authors: Libber
authors: Orthopedics and Rehabilitation, University of Wisconsin-Madison, Madison, WI, USA; Intercollegiate Athletics, University of Wisconsin-Madison, Madison, WI, USA.
authors: Bryan
authors: B
authors: Heiderscheit
authors: Intercollegiate Athletics, University of Wisconsin-Madison, Madison, WI, USA.
authors: Jennifer
authors: J
authors: Sanfilippo
authors: Essentia Institute of Rural Health, Duluth, MN, USA.
authors: Brian
authors: B
authors: Johnson
authors: Essentia Institute of Rural Health, Duluth, MN, USA.
authors: Irina
authors: I
authors: Haller
authors: Osteoporosis Clinical Research Program, University of Wisconsin-Madison, Madison, WI, USA. Electronic address: nbinkley@wisc.edu.
authors: Neil
authors: N
authors: Binkley
mesh_terms: D015502:Absorptiometry, Photon; D000273:Adipose Tissue; D000293:Adolescent; D056352:Athletes; D001823:Body Composition; D015992:Body Mass Index; D049628:Body Size; D005260:Female; D006801:Humans; D008297:Male; D018482:Muscle, Skeletal; D015203:Reproducibility of Results; D012737:Sex Factors; D051598:Whole Body Imaging; D055815:Young Adult
keywords: Body composition; DXA; precision; sports performance