Müller M J, Grund A, Krause H, Siewers M, Bosy-Westphal A, Rieckert H
Institut für Humanernährung und Lebensmittelkunde, (Abteilung Ernährung des Menschen) der Christian-Albrechts Universität zu Kiel, Germany.
Br J Nutr. 2002 Nov;88(5):545-54. doi: 10.1079/BJN2002698.
The aim of the present study was to compare variables of metabolism, physical activity and fitness to body composition in normal and overweight children in a cross-sectional study design. Body composition was assessed by anthropometric measurements and bioelectrical impedance analysis in forty-eight prepubertal children (age 5-11 years, thirteen normal-weight, thirty-five overweight). Total energy expenditure (EE) was measured by combination of indirect calorimetry (for measurement of resting EE) and individually calibrated 24 h heart-rate (HR) monitoring. Activity-related EE and physical activity level (PAL) were calculated. Time spent with min-by-min HR>FLEX HR was also used as a marker of moderate habitual and vigorous activities. Aerobic fitness (O2 pulse (O2 consumption:HR at submaximal steady-state heart rate), submaximal O2 consumption (VO2submaximal), RER at a HR of 170 beats per min) was determined by bicycle ergometry. Muscle strength of the legs (maximal isometric strength of musculus quadriceps and of musculus ischiocruralis (Fa max and Fb max respectively)) was measured by computer tensiometry. When compared with normal children, overweight children had higher skinfold thicknesses (sum of skinfold thicknesses at four sites +160 %), fat mass (+142 %), waist (+24 %) and hip circumferences (+14 %), resting EE (+13 %) and RER (+5 %). No significant group differences were found for fat-free mass, muscle mass, total EE, activity-related EE, PAL, HR>FLEX HR, VO2submaximal, O2 pulse, Fa max and Fb max as well as the fat-free mass- or muscle mass-adjusted values for resting EE, aerobic fitness and muscle strength. When compared with normal children, overweight children had a lower measured v. estimated resting EE (Delta resting EE) and spent more time watching television. There were positive relationships between fat-free mass(x) and resting EE(x), total EE(y), aerobic fitness(y) and muscle strength(y), but only Delta resting EE(x) and HR>FLEX HR(x) correlated with fat mass(y). In a stepwise multivariate regression analysis resting EE adjusted for fat-free mass and Delta resting EE were significant determinants of % fat mass and explained 29.7 % of its variance. Thus, in the present cross-sectional study, resting EE was the most important determinant of fat mass.
本研究的目的是在一项横断面研究设计中，比较正常和超重儿童的代谢、身体活动及体能变量与身体成分之间的关系。通过人体测量和生物电阻抗分析，对48名青春期前儿童（年龄5 - 11岁，13名正常体重，35名超重）的身体成分进行了评估。总能量消耗（EE）通过间接测热法（用于测量静息EE）和个体校准的24小时心率（HR）监测相结合的方法进行测量。计算了与活动相关的EE和身体活动水平（PAL）。每分钟HR > FLEX HR的时间也被用作中度习惯性和剧烈活动的指标。通过自行车测力计测定有氧适能（O2脉搏（次最大稳态心率时的耗氧量：HR）、次最大耗氧量（VO2submaximal）、每分钟170次心率时的呼吸交换率（RER））。通过计算机张力测定法测量腿部肌肉力量（股四头肌和坐骨神经肌肉的最大等长力量（分别为Fa max和Fb max））。与正常儿童相比，超重儿童的皮褶厚度更高（四个部位皮褶厚度之和 +160%）、脂肪量更高（+142%）、腰围更高（+24%）和臀围更高（+14%）、静息EE更高（+13%）和RER更高（+5%）。在去脂体重、肌肉量、总EE、与活动相关的EE、PAL、HR > FLEX HR、VO2submaximal、O2脉搏、Fa max和Fb max以及静息EE、有氧适能和肌肉力量的去脂体重或肌肉量调整值方面，未发现显著的组间差异。与正常儿童相比，超重儿童的实测与估计静息EE差值（Delta静息EE）更低，且看电视时间更长。去脂体重（x）与静息EE（x）、总EE（y）、有氧适能（y）和肌肉力量（y）之间存在正相关关系，但只有Delta静息EE（x）和HR > FLEX HR（x）与脂肪量（y）相关。在逐步多元回归分析中，经去脂体重调整的静息EE和Delta静息EE是脂肪量百分比的重要决定因素，解释了其29.7%的方差。因此，在本横断面研究中，静息EE是脂肪量的最重要决定因素。
