利用生物电阻抗法分析西藏藏族青少年脂肪分布特点

目的 利用生物电阻抗分析法测量西藏藏族青少年身体各部脂肪含量的数值,提出适合西藏藏族青少年的脂肪含量基准值,探讨西藏藏族青少年的脂肪分布特点与规律。方法 在知情同意的前提下,随机抽取1427例(男为710例,女为717例)父母均为藏族的西藏藏族健康青少年作为研究对象,应用体成分分析仪对所有受试者进行检测,得出脂肪总量、左上肢（左下肢、右上肢、右下肢、躯干）脂肪量等与脂肪相关的数值,进而推算出体脂肪率、左上肢（左下肢、右上肢、右下肢、躯干）脂肪率。所有结果输入SPSS 19.0统计学软件,进行独立样本t检验和方差分析统计学处理。结果 西藏藏族青少年各年龄段的脂肪总量、四肢脂肪量、躯干脂肪量,男性均低于女性（P <0.05）。总体西藏藏族青少年的脂肪含量随年龄增长而增加,女性的增加趋势更加显著。结论 西藏藏族青少年的脂肪含量随年龄变化特点与体内激素分泌水平有关,体现了不同发育时期的生理特点。     

利用生物电阻抗法对进藏工作汉族男性成年人群与西藏藏族男性成年人群脂肪含量进行比较分析

目的 运用生物电阻抗分析法,通过测量得出进藏工作汉族男性成年人群与西藏藏族男性成年人群脂肪含量的数值,并对两者进行对比分析,进而探讨进藏工作汉族男性成年人群与西藏藏族男性成年人群脂肪含量及分布的不同。 方法 在知情同意的情况下,整体随机抽取进藏工作汉族男性与西藏藏族男性健康成人作为研究对象,共选取337人(汉族男性为164例,藏族男性为173例),应用体成分分析仪,对所有受试者进行检测,得出脂肪总量、左上肢（左下肢、右上肢、右下肢、躯干）脂肪量,进而推算出体脂肪率、左上肢（左下肢、右上肢、右下肢、躯干）脂肪率。所有结果输入SPSS19.0统计软件包,进行独立样本t检验和方差分析统计学处理。 结果 进藏工作汉族男性成年人群的各项脂肪含量数值均小于西藏藏族男性成年人群,而且差异具有显著性（P＜0.01或P＜0.05）。进藏工作汉族男性成年人群与西藏藏族男性成年人群的脂肪含量随年龄变化的趋势基本一致,各部位的脂肪含量和脂肪率均随年龄增加而增大。脂肪量的增加均在30岁年龄组到40岁年龄组增加明显,此后体脂含量增加减慢,甚至50岁年龄组的汉族人群的下肢脂肪含量出现了轻度下降。结论 整体上,进藏工作汉族男性成年人群的各项脂肪含量数值均小于西藏藏族男性成年人群。进藏工作汉族男性成年人群和西藏藏族男性成年人群脂肪含量随年龄的增长发生变化,总体呈上升趋势,但不同部位的脂肪变化趋势略有不同。     

利用生物电阻抗法分析辽宁汉族成人脂肪分布特点

目的 运用生物电阻抗分析法,测量辽宁汉族成人身体各部份脂肪含量,提出适合于辽宁汉族群体的脂肪含量基准值,进而探讨辽宁汉族成人的脂肪分布特点与规律。 方法 在知情同意的前提下,随机抽取父母均为汉族的辽宁汉族健康成人作为研究对象,共选取1034人(男性379例,女性655例)。应用体成分分析仪,对所有受试者进行检测,得出脂肪总量、去脂体重、内脏脂肪等级、左上肢（左下肢、右上肢、右下肢、躯干）脂肪量等与脂肪相关的各项数值,进而推算出体脂肪率、左上肢（左下肢、右上肢、右下肢、躯干）脂肪率。结果采用SPSS统计学软件,进行独立样本t检验和方差分析处理。 结果 多数年龄段,男性的脂肪总量、四肢脂肪量、躯干脂肪量均低于女性（ EM>P /EM><0.01）,     

利用生物电阻抗法研究进藏工作的汉族人群骨骼肌含量

目的 探讨进藏工作汉族成年人群和辽宁汉族成年人群骨骼肌含量分布的特点及差异.方法 随机抽取进藏工作的辽宁本地汉族、辽宁汉族健康成人作为研究对象,共选取进藏辽宁本地汉族成人223名(男95,女128);辽宁汉族成人302名(男126,女176),应用体成分分析仪对受试者的体重、全身肌肉量、躯干肌肉量、左上肢肌肉量、右上肢...     

甘肃及西藏藏族成人体成分分析

目的收集我国藏族居民体成分数据并比较甘肃、西藏藏族成人体成分各指标差异,揭示藏族成人体成分分布的特点。方法采用整群抽样法抽取西藏藏族自治区日喀则市,甘肃省甘南藏族自治州、天祝藏族自治县藏族成年居民共814名,采用生物电阻抗法检测受试者体成分各项指标,比较两省区藏族成年人体成分数据的差异。结果藏族成年男性身体质量指数(BMI)、去脂体重、体脂肪率、内脏脂肪量、皮下脂肪量、肌肉量、身体水分及蛋白质量、腰臀比(WHR)均在40~50岁达到峰值,基础代谢在40~50岁后随着年龄的增长下降,细胞内外液比值(E/I)随年龄的增长而升高;女性去脂体重、肌肉量、基础代谢在30~40岁达到高峰,身体水分量在40~50岁达到最大值;BMI、体脂肪率、内脏脂肪量、皮下脂肪量、WHR及E/I均随年龄的增高而升高,而蛋白质量随年龄增高而下降。甘肃藏族BMI、去脂体重、肌肉量、皮下脂肪量、内脏脂肪量、身体水分、基础代谢、超重肥胖比率均高于西藏藏族,西藏藏族成人WHR过高的比率高于甘肃藏族,差异有统计学意义(P0.05)。结论我国藏族成人男性及女性体成分中脂肪相关指标随年龄增长分别呈正弦曲线及单向增高变化;不同地域藏族成人体成分也存在差异,甘肃藏族成人体成分多项指标尤其是大部分体脂肪相关指标高于西藏藏族成人,可能会导致甘肃藏族成人慢性病发病率较高。     

宁夏汉族青少年脂肪分布特点的分析

目的:分析宁夏汉族不同年龄段、不同性别青少年脂肪的分布特点。方法:采用生物电阻抗分析法,分析1831例宁夏汉族不同年龄段青少年(男性911例,女性920例)脂肪的分布规律,比较各指标均值在性别间的差异性。结果:宁夏汉族青少年脂肪总量、总体脂率及身体各部分(左上肢、左下肢、右上肢、右下肢、躯干)脂肪量和体脂率总体呈现随年龄变化而上升的特点;不同性别宁夏汉族青少年脂肪总量及总体脂率,身体各部分脂肪量及体脂率均值女性均高于男性,脂肪总量(9～19岁)、总体脂率(7～19岁),左上肢、躯干(12～19岁)、左下肢、右下肢(9～19岁)、右上肢(11～19岁)脂肪量及左上肢、左下肢(9～19岁)、右上肢、右下肢(7～19岁)、躯干(11～19岁)体脂率差异有统计学意义。结论:宁夏汉族青少年脂肪的分布具有性别差异,脂肪分布随年龄变化的特点可能与体内激素分泌水平有关。     

西藏藏族成人体成分与骨量异常的相关性

目的探讨西藏藏族成人骨强度指数的变化特点,并分析骨量异常与体成分的相关性。方法抽取西藏藏族自治区日喀则市藏族成人560例,采用生物电阻抗分析仪及超声骨密度仪分别测量被研究者体成分各指标及右足跟骨骨强度指数、T值等,采用非条件Logistic回归法分析骨量异常与体成分间的关系。结果西藏藏族男女性成人骨强度指数均在18~30岁达到峰值,之后随年龄增长而下降;50岁以上男女性骨质疏松症检出率分别为7.6%及11.7%;Binary Logistic回归分析显示,年龄(B=0.046,OR=1.047,P0.01)、内脏脂肪量(B=0.452,OR=1.572,P0.05)是西藏藏族成人发生骨量异常的危险因素,而皮下脂肪含量(B=-0.181,OR=0.835,P0.01)及肌肉量(B=-0.055,OR=0.947,P0.05)是骨量异常的保护性因素,腰臀比与骨量异常无相关性。结论西藏藏族50岁以上人群骨质疏松症发病率相对国内其他报道的民族同龄人群较低;内脏脂肪量越高、皮下脂肪量及肌肉量越低者,发生骨量下降及骨质疏松症的危险性越高。     

基于生物电阻抗法的人体成分测量系统的研究与评价

目的：本文探讨了生物电阻抗测量系统对人体成分的测量效果与适用性。从而为测量人体成分时选择合适的测量系统提供了技术支持与理论依据。方法：对生物电阻抗测量系统进行了深人的研究与评价,剖析总结了生物电阻抗法测量系统存在的问题,并对生物电阻抗法测量人体成分的影响因素进行了归纳与总结,最后对生物电阻抗法测量人体成分的未来发展进行了展望。结果：生物电阻抗法测量系统经历了从单频率全身测量系统到多频率人体分段电阻抗测量系统的发展过程,测量系统本身所具有的特性及外界因素都会对整个测量系统有一定干扰,所以针对不同的测量需要选择合适的测量系统与测量方案可以最大限度的减少干扰。结论：生物电阻抗法是测量人体成分的理想方法,生物电阻抗法测量系统的选择是人体成分测量的关键。随着研究推进,将会出现适用于人体局部的电阻抗测量系统。     

甘肃裕固族成人脂肪分布及变化特点分析

目的探讨甘肃裕固族成人脂肪分布及变化特点,为该民族人群健康指导及相关疾病的研究提供参考。方法采用分层整群随机抽样方法,应用生物电阻抗体成分分析仪测量1086例甘肃裕固族成人,其中男性336例,女性720例的脂肪相关体成分指标。结果甘肃省裕固族成年女性的总脂肪量、皮下脂肪含量、躯干及四肢脂肪量均高于男性(P0.01);内脏脂肪含量无显著性差异(P0.05)。不同年龄段身体各脂肪含量男、女性比较,女性的总脂肪量、躯干脂肪量、四肢脂肪量、皮下脂肪量均高于男性(P0.01),内脏脂肪含量比较差异无显著性(P0.05);裕固族成人体脂含量随年龄的增长均呈上升趋势,20~29岁年龄段到40~49岁年龄段前期为快速增长期,在60~69岁年龄段达到峰值后呈缓慢下降,双下肢脂肪含量在40~49岁年龄段达峰值,女性脂肪含量上升趋势和下降趋势较男性均更为显著。结论甘肃省裕固族成人内脏脂肪含量无性别差异,其余各部位脂肪量女性均高于男性;甘肃裕固族成年人总脂肪量和身体各部位脂肪含量随着年龄增长总体呈上升趋势,之后在60~69岁年龄段后期开始下降。     

甘肃裕固族成人骨强度和体成分变化特点及相关性分析

目的分析甘肃裕固族成人骨强度和体成分随年龄变化特征并探讨骨强度与体成分的相关性。方法2015年7月至2016年8月选取甘肃省肃南裕固族自治县成人725例(男性354例,女性371例),年龄20~86岁,采用超声骨密度仪和生物电阻抗分析仪,分别测量跟骨骨强度及体成分指标。结果甘肃裕固族成年男性骨强度在20~29岁低于女性(P0.05),50岁后高于女性(P0.01);男性各年龄段的肌肉量均高于女性(P0.01);各年龄段的总脂肪量、皮下脂肪含量均低于女性(P0.01);内脏脂肪含量仅在20~29岁及70岁后低于女性(P0.01)。男女骨强度分别在30~39岁和20~29岁达峰值、50~59岁和40~49岁开始较前出现差异(P0.05),男性在70岁后和女性在50岁后骨强度低于之前各年龄组(P0.01)。男性躯干及四肢肌肉量均在40~49岁及60~69岁呈现双峰,女性躯干及四肢肌肉量均在40~49岁达峰值。甘肃裕固族成年身体各部位的脂肪含量变化同步,男女性分别在60~69岁和50~59岁达峰值。多元线性逐步回归分析显示,骨强度与四肢肌肉量和皮下脂肪量正相关(P0.01),与内脏脂肪量负相关(P0.01)。结论随年龄增长,甘肃裕固族成人身体各部位的同种体成分呈同步变化,女性骨强度较男性下降时间早且速度快。裕固族成人骨强度由肌肉和脂肪共同决定且与其分布部位有关。裕固族70岁以上男性及50岁以上女性是骨质疏松性防治的重点人群;男女性应分别从50岁后和40岁后应加强肢体锻炼、增加四肢肌肉量、控制内脏脂肪,预防骨质疏松。     

Estimation of maximal oxygen uptake by bioelectrical impedance analysis

Previous non-exercise models for the prediction of maximal oxygen uptake VO(2max) have failed to accurately discriminate cardiorespiratory fitness within large cohorts. The aim of the present study was to evaluate the feasibility of a completely indirect method for predicting VO(2max) that was based on bioelectrical impedance analysis (BIA) in 66 young, healthy fit men and women. Multiple, stepwise regression analysis was used to determine the usefulness of BIA and additional covariates to estimate VO(2max) (ml min(-1)). BIA was highly correlated to VO(2max) (r = 0.914; P < 0.001) and entered the regression equation first. The inclusion of gender and a physical activity rating further improved the model which accounted for 88% of the variance in VO(2max) and resulted in a relative standard error of the estimate (SEE) of 7.2%. Substantial agreement between the methods was confirmed by the fact that nearly all the differences were within +/-2 SD. Furthermore, in contrast to previously published non-exercise models, no trend of a reduction in prediction accuracy with increasing VO(2max) values was apparent. It was concluded that a non-exercise model based on BIA might be a rapid and useful technique to estimate VO(2max), when a direct test does not seem feasible. However, though the present results are useful to determine the viability of the method, further refinement of the BIA approach and its validation in a large, diverse population is needed before it can be applied to the clinical and epidemiological settings.     

Estimation of extracellular space and blood volume using bioelectrical impedance measurements

Summary The bromide-82 dilution space (extracellular space, ECS) and blood volume (BV) were measured in 21 patients with esophageal and gastric cancer and in 27 patients 18–96 months after total gastrectomy. Resistance (R) and reactance (X_c) from bioelectrical impedance measurements were used to obtain multiple regression equations for ECS and BV. The variables weight, gender, and height ²/X_c were independent predictors of ECS (r = 0.767; P < 0.0001). Height 2/R and gender were predictors of blood volume (r = 0.856; P < 0.0001). The mean difference between the Br space and the ECS predicted from impedance measurements was 0 ± 1.54 (mean ± SD). The limits of agreement (± 2 SD) were therefore ±3.081 or 19.6% of the mean Br space of 15.71. The limits of agreement for BV were ±789 ml or ±19.7% of the average BV of 4008 ml. It is concluded that bioelectrical impedance plethysmography using a single frequency can be used for the estimation of ECS and BV The wide limits of agreement, however, may limit its used in clinical practice.Abbreviations ECS extracellular space - BV blood volume - R resistance - X_c reactance - SD standard deviation - LBM lean body mass - TBW total body water - RCM red blood cell mass - cAMA corrected arm muscle area - Z impedance - ANOVA analysis of variance - NS not significant - Na_e/K_c exchangeable sodium to exchangeable potassium ratio - p specific resistivity - PV plasma volume     

Validity of bioelectrical impedance and ultrasonographic methods for estimating the muscle volume of the upper arm

The present study aimed to investigate the validity of bioelectrical impedance and ultrasonographic methods for predicting the muscle volume of the upper arm. Bioelectrical impedance of the right upper arm and the thickness of elbow flexor and extensor muscles were measured from 26 healthy young adult men using a specially designed bioelectrical impedance data acquisition system and brightness-mode ultrasound apparatus, respectively. As reference data, the muscle volume (MV_MRI) of the right upper arm was determined using a magnetic resonance imaging method. The impedance index was calculated as L ²/Z, where L is the upper arm length and Z is the impedance of the shoulder to the elbow. The muscle volume (MV_ULT) was calculated as π·(d/2)²·L, where d is muscle thickness. L ²/Z and MV_ULT were significantly correlated with MV_MRI with correlation coefficients of 0.971 and 0.962, respectively. In these relationships, the standard errors of estimation were 44.2 cm³ (6.3%) for L ²/Z and 50.7 cm³ (7.2%) for MV_ULT. There was no significant difference between the absolute errors of muscle volumes estimated by L ²/Z and MV_ULT: 36.2 (4.8, SEM) cm³ for L ²/Z versus 40.3 (5.8) cm³ for MV_ULT. The present results suggest that both bioelectrical impedance and ultrasonographic methods may be useful for predicting the muscle volume of the upper arm. Accepted: 7 March 2000     

Critical factors and their impact on bioelectrical impedance analysis in children: a review

Several guidelines for bioelectrical impedance analysis (BIA) have been prepared for adults, but not for children. For that reason, there is a pressing need to develop a consensus set of guidelines to facilitate standardisation of BIA in this important group. This review provides an introduction to BIA, highlights critical factors that may impact on BIA and identifies areas where there is a need for further research in order to increase the quality of impedance measurements and prediction of body composition in children. Although the results of this review highlights a lack of studies in children to provide definitive BIA guidelines, the technique has, however, still proven valuable for body composition assessment in ill and healthy children. To fill the gaps in our knowledge, future studies should focus on methodological issues, particularly with regard to hydration, voiding, clothing, skin preparation and body position. The review may advantageously be used as a checklist in the planning of future studies. Finally, this review forms the basis for the development of guidelines for BIA assessment in this particular group; a task appropriately to be undertaken by scientific societies within the field.     

Comparison of three segmental multifrequency bioelectrical impedance techniques in healthy adults

Background: The analysis of segmental or limb bioimpedance has gained importance in human population biology. However, standardized measurement techniques are needed.

Aim: This study compared three techniques for segmental analysis (T1, conventional electrode measurement; T2, use of a novel additional switching unit; T3, equipotentials instead of switching unit) which are often used in population biology.

Subjects and methods: The techniques were compared in 124 healthy adults (19–83 years) using a tetrapolar bioimpedance analyser (Nutriguard-M) at multiple frequencies (5, 50, 100 kHz) to gain whole-body and segmental resistances, reactances and phase angles.

Results: Repeated measures ANOVA yielded a significant technique effect for most variables (26/27), a significant interaction technique × sex for half (13/27), and a significant interaction technique × age for a quarter (7/27) of variables.

Conclusions: Differences exist between the three techniques which are primarily caused by inconsistent current pathways. A comparison with literature data showed that, in addition, subject's posture during measurement, electrode contact and electrode site may lead to inconsistent resistance and reactance values. This makes comparisons between different populations difficult. Therefore, this study recommends generally using the T2 technique which is standardized, easy to use and, thereby, well suited for field studies in large population groups.