Kerr Ava, Slater Gary J, Byrne Nuala
1School of Health and Sport Sciences,University of the Sunshine Coast,Sippy Downs,QLD 4556,Australia.
2School of Health Sciences, Faculty of Health,University of Tasmania,Launceston,TAS 7250,Australia.
Br J Nutr. 2017 Feb;117(4):591-601. doi: 10.1017/S0007114517000551.
Two, three and four compartment (2C, 3C and 4C) models of body composition are popular methods to measure fat mass (FM) and fat-free mass (FFM) in athletes. However, the impact of food and fluid intake on measurement error has not been established. The purpose of this study was to evaluate standardised (overnight fasted, rested and hydrated) v. non-standardised (afternoon and non-fasted) presentation on technical and biological error on surface anthropometry (SA), 2C, 3C and 4C models. In thirty-two athletic males, measures of SA, dual-energy X-ray absorptiometry (DXA), bioelectrical impedance spectroscopy (BIS) and air displacement plethysmography (BOD POD) were taken to establish 2C, 3C and 4C models. Tests were conducted after an overnight fast (duplicate), about 7 h later after ad libitum food and fluid intake, and repeated 24 h later before and after ingestion of a specified meal. Magnitudes of changes in the mean and typical errors of measurement were determined. Mean change scores for non-standardised presentation and post meal tests for FM were substantially large in BIS, SA, 3C and 4C models. For FFM, mean change scores for non-standardised conditions produced large changes for BIS, 3C and 4C models, small for DXA, trivial for BOD POD and SA. Models that included a total body water (TBW) value from BIS (3C and 4C) were more sensitive to TBW changes in non-standardised conditions than 2C models. Biological error is minimised in all models with standardised presentation but DXA and BOD POD are acceptable if acute food and fluid intake remains below 500 g.
身体成分的二室、三室和四室（2C、3C和4C）模型是测量运动员体脂量（FM）和去脂体重（FFM）的常用方法。然而，食物和液体摄入对测量误差的影响尚未明确。本研究的目的是评估标准化（过夜禁食、休息且补水）与非标准化（下午且未禁食）状态对体表测量法（SA）、2C、3C和4C模型的技术误差和生物学误差的影响。对32名男性运动员进行SA、双能X线吸收法（DXA）、生物电阻抗光谱法（BIS）和空气置换体积描记法（BOD POD）测量，以建立2C、3C和4C模型。在过夜禁食后（重复测量）、随意进食和饮水约7小时后以及在摄入特定餐食前后24小时进行测试。确定测量的平均误差和典型误差的变化幅度。在BIS、SA、3C和4C模型中，非标准化状态和餐后测试的FM平均变化得分相当大。对于FFM，非标准化条件下BIS、3C和4C模型的平均变化得分变化较大，DXA变化较小，BOD POD和SA变化极小。包含来自BIS的全身水（TBW）值的模型（3C和4C）在非标准化条件下比2C模型对TBW变化更敏感。标准化状态下所有模型的生物学误差最小，但如果急性食物和液体摄入量保持在500克以下，DXA和BOD POD也是可以接受的。
