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Sub-Regional Tissue Morphometry in Male Athletes and Controls Using Dual X-Ray Absorptiometry (DXA)

Arthur D. Stewart and James Hannan

Athletes have traditionally been evaluated for body composition by percent fat, percent muscle, and somatotype. Since the late 1980s, dual X-ray absorptiometry (DXA) has offered total and regional body composition of bone mineral content (BMC), lean tissue and fat, but studies involving athletes are rare (11) and have not included regional tissue distribution. In the present study, DXA was used to compare a total of 121 male subjects belonging to 9 different athletic groups and controls. ANOVA showed total tissue percent BMC, lean tissue, and fat were significantly different between the various athletic groups (p < .001). Regional differences in tissue distribution between different athletic groups affect BMC and lean tissue (p < .001), but not fat (p > .05). However, athletes of the leanest groups had different fat distribution to that of nonexercising controls (p < .01). It appears that fat distribution is nonspecific in its response to exercise, while lean and BMC distributions show highly specific adaptations to specific sports.

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Skinfold Prediction Equations Fail to Provide an Accurate Estimate of Body Composition in Elite Rugby Union Athletes of Caucasian and Polynesian Ethnicity

Adam J. Zemski, Elizabeth M. Broad, and Gary J. Slater

body composition are surface anthropometry and dual-energy X-ray absorptiometry (DXA) ( Ackland et al., 2012 ; Zemski et al., 2015 ). Surface anthropometry, which includes the indirect assessment of subcutaneous fat, is an easily accessible, inexpensive, mobile, and robust method of assessment. The

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Development of an Anthropometric Prediction Model for Fat-Free Mass and Muscle Mass in Elite Athletes

Erik Sesbreno, Gary Slater, Margo Mountjoy, and Stuart D.R. Galloway

performance in the field. Dual-energy X-ray absorptiometry (DXA) is increasingly integrated into the monitoring of athletic populations to provide timely information on both absolute and relative whole-body and regional body composition, plus bone health ( Meyer et al., 2013 ). However, without careful

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Validation of a Multielectrode Bioelectrical Impedance Analyzer With a Dual-Energy X-Ray Absorptiometer for the Assessment of Body Composition in Older Adults

Nathan F. Meier, Yang Bai, Chong Wang, and Duck-chul Lee

Body composition is a significant health indicator. A wide range of devices and methods are available for its measurement, such as underwater weighing, skinfold testing, body mass index, dual-energy X-ray absorptiometry (DXA), and bioelectrical impedance analysis (BIA). Changes in body composition

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Reliability and Precision of the Nana Protocol to Assess Body Composition Using Dual Energy X-Ray Absorptiometry

Flinn Shiel, Carl Persson, Vini Simas, James Furness, Mike Climstein, Rod Pope, and Ben Schram

Dual energy X-ray absorptiometry (DXA) uses a machine originally developed to provide information about bone mineral density, with the additional capability to assess and analyze body composition (BC) while imparting only low levels of radiation (less than a thousandth of the maximum recommended

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Longitudinal Changes in Body Composition Assessed Using DXA and Surface Anthropometry Show Good Agreement in Elite Rugby Union Athletes

Adam J. Zemski, Shelley E. Keating, Elizabeth M. Broad, and Gary J. Slater

measures are unable to accurately quantify absolute ( Doran et al., 2014 ; Reilly et al., 2009 ; Zemski et al., 2018 ), or changes in, FFM and FM ( Silva et al., 2009 ). Given this limitation, anthropometric data are increasingly being complemented by other measures. Dual-energy X-ray absorptiometry (DXA

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Exclusion of Trunk Region Reduces Biological Error but Increases Technical Error of DXA Lean Soft Tissue Estimates From Nonfasted Assessments

Grant M. Tinsley and Brett S. Nickerson

of common methods, including dual-energy X-ray absorptiometry (DXA). However, the requirement of an overnight fasting period imposes limitations for when and how many assessments can be conducted. Nonetheless, the importance of an overnight fast prior to DXA assessment has been confirmed by reports

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Errors in Dual Energy X-Ray Absorptiometry Estimation of Body Composition Induced by Hypohydration

Nidia Rodriguez-Sanchez and Stuart D.R. Galloway

Dual energy x-ray absorptiometry (DXA) is a popular tool to determine body composition (BC) in athletes, and is used for analysis of fat-free soft tissue mass (FFST) or fat mass (FM) gain/loss in response to exercise or nutritional interventions. The aim of the current study was to assess the effect of exercise-heat stress induced hypohydration (HYP, >2% of body mass (BM) loss) vs. maintenance of euhydration (EUH) on DXA estimates of BC, sum of skinfolds (SF), and impedance (IMP) measurements in athletes. Competitive athletes (23 males and 15 females) recorded morning nude BM for 7 days before the first main trial. Measurements on the first trial day were conducted in a EUH condition, and again after exercise-heat stress induced HYP. On the second trial day, fluid and electrolyte losses were replaced during exercise using a sports drink. A reduction in total BM (1.6 ± 0.4 kg; 2.3 ± 0.4% HYP) and total FFST (1.3 ± 0.4 kg), mainly from trunk (1.1 ± 0.5 kg), was observed using DXA when participants were HYP, reflecting the sweat loss. Estimated fat percent increased (0.3 ± 0.3%), however, total FM did not change (0.1 ± 0.2 kg). SF and IMP declined with HYP (losses of 1.5 ± 2.9% and 1.6 ± 3% respectively) suggesting FM loss. When EUH was maintained there were no significant changes in BM, DXA estimates, or SF values pre to post exercise, but IMP still declined. We conclude that use of DXA for FFST assessment in athletes must ensure a EUH state, particularly when considering changes associated with nutritional or exercise interventions.

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A 5-Year Analysis of Weight Cycling Practices in a Male World Champion Professional Boxer: Potential Implications for Obesity and Cardiometabolic Disease

James C. Morehen, Carl Langan-Evans, Elliot C.R. Hall, Graeme L. Close, and James P. Morton

using dual-energy X-ray absorptiometry (DXA, QDR Series Discovery A, version 12:4:3; Hologic Inc., Bedford, MA) according to the DXA Best Practice Protocol ( Nana et al., 2015 , 2016 ). The frequency of DXA scans complied with the regulations from the Committee on Medical Aspects of Radiation in the

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Body Composition Asymmetry in University Rugby Players: Influence of Sex, Position, and Injury

Tamara R. Cohen, Brent Rosenstein, Amanda Rizk, Stephane Frenette, and Maryse Fortin

). Thirty-seven rugby players (22 women, 15 men) volunteered to participate in this study. Players were recruited through respective coaching staff. Inclusion criteria included players >18 years of age who were able to undergo a dual-energy X-ray absorptiometry (DXA) assessment. Exclusion criteria included