Mueller William H., Harrist Ronald B., Doyle Suzanne R., Ayars Candace L., Labarthe Darwin R.
University of Texas-Houston Health Science Center Graduate School of Public Health, Houston, Texas 77225.
Am J Hum Biol. 1999;11(1):69-78. doi: 10.1002/(SICI)1520-6300(1999)11:1<69::AID-AJHB7>3.0.CO;2-T.
Project HeartBeat! is a four year mixed-longitudinal study of the development of cardiovascular risk factors in White and African American children who at baseline comprised three age cohorts 8, 11, and 14 years. This paper focuses on the anthropometric variables which were chosen to reflect body fat and fat-free mass. Selected anthropometric dimensions are compared with those of samples from the combined National Health and Nutrition Examination Surveys I and II to explore the similarities of the samples in terms of central tendencies and variances. The measurements were then explored in terms of their ability to estimate the two compartment model of body composition: fat-free mass (FFM) and body fat (BF) from bioelectrical impedance (BIA). Project HeartBeat! children are slightly larger than NHANES children and have variances that are generally comparable to the national surveys. Over seven percent (7.7%) of children were overweight (BMI) and 25% had 'mild obesity' by %BF. Three different factor analytic methods (incomplete principal components, alpha and maximum likelihood) produced two latent variables from 17 anthropometric dimensions which together accounted for 76-83% of the variation: (1) A body mass factor (F1) which was weighted highly on six circumferences, weight and six skinfolds, and (2) a linear growth factor (F2) which was strongly associated with height, arm length, and sitting height. Triceps, subscapular and midaxillary skinfolds were consistently highly loaded on the body mass factor and their sum was highly correlated to %BF and fat mass (0.90-0.99). This suggests that this sum could be used to estimate fatness in children in studies where the BIA or other body composition techniques are unavailable. FFM and %BF were predicted from the anthropometric factors. Both factors contributed to the estimate of FFM (R(2) = 0.81-0.93), although F2 contributed proportionately more. The 'body mass' factor (F1) was the main predictor of %BF (R(2) = 0.86-0.93), though at some ages the linear factor (F2) was significantly and negatively related to %BF. This set of anthropometric dimensions, taken for the purpose of estimating body composition and summarized as two latent vectors by factor analysis, strongly reflects body fat and FFM in children and adolescents. Am. J. Hum. Biol. 11:69-78, 1999. Copyright 1999 Wiley-Liss, Inc.
“心跳计划！”是一项为期四年的混合纵向研究，旨在研究白人和非裔美国儿童心血管危险因素的发展情况。这些儿童在基线时分为三个年龄组，分别为8岁、11岁和14岁。本文重点关注人体测量学变量，这些变量被选来反映身体脂肪和去脂体重。将选定的人体测量维度与来自全国健康和营养检查调查一期和二期合并样本的维度进行比较，以探讨样本在集中趋势和方差方面的相似性。然后，根据这些测量值估计身体成分两室模型的能力进行研究：通过生物电阻抗（BIA）测量去脂体重（FFM）和身体脂肪（BF）。“心跳计划！”的儿童比美国国家健康和营养检查调查（NHANES）的儿童略大，其方差通常与全国性调查相当。超过7%（7.7%）的儿童超重（身体质量指数），25%的儿童体脂百分比处于“轻度肥胖”水平。三种不同的因子分析方法（不完全主成分法、α法和最大似然法）从17个人体测量维度中得出两个潜在变量，它们共同解释了76% - 83%的变异：（1）一个体重因子（F1），在六个周长、体重和六个皮褶厚度上权重较高；（2）一个线性生长因子（F2），与身高、臂长和坐高密切相关。肱三头肌、肩胛下和腋中皮褶厚度在体重因子上的载荷一直很高，它们的总和与体脂百分比和脂肪量高度相关（0.90 - 0.99）。这表明，在无法使用BIA或其他身体成分技术的研究中，这个总和可用于估计儿童的肥胖程度。根据人体测量因子预测FFM和体脂百分比。两个因子都对FFM的估计有贡献（R² = 0.81 - 0.93），尽管F2的贡献相对更大。“体重”因子（F1）是体脂百分比的主要预测因子（R² = 0.86 - 0.93），不过在某些年龄段，线性因子（F2）与体脂百分比呈显著负相关。这组用于估计身体成分并通过因子分析总结为两个潜在向量的人体测量维度，强烈反映了儿童和青少年的身体脂肪和FFM。《美国人类生物学杂志》11:69 - 78，1999年。版权所有1999年威利 - 利斯公司。
