Forman J N, Miller W C, Szymanski L M, Fernhall B
Exercise Science Programs, The George Washington University Medical Center, Washington, DC 20052, USA.
Int J Obes Relat Metab Disord. 1998 Mar;22(3):215-21. doi: 10.1038/sj.ijo.0800569.
To compare resting metabolic rates (RMR) of African-American (n = 25) and Caucasian (n = 22) premenopausal (35+/-1 y, Mean +/- s.e.m.) women who are obese (95.2+/-2.9 kg, body mass index (BMI) = 34.7+/-0.9, % body fat = 45.2+/-0.9), inactive and free from metabolic disorders or medications that would affect heart rate or RMR.
RMR and respiratory exchange ratio (RER) by indirect calorimetry, body composition by plethysmography, maximal aerobic capacity (VO2max) and girth measurements.
Group mean comparisons were made with a Student's t-test or an ANCOVA, which controlled for individual differences in body weight and lean body mass (LBM). Significance was set at P < 0.05. Groups were not significantly different in age, height, weight, BMI, % body fat, fat mass, RER, VO2max, resting heart rate, maximal heart rate; or chest, waist, hip, arm, thigh or calf circumferences. After adjusting for body weight, RMR (I O2/min) for African-Americans (0.254+/-0.007) was significantly lower (9%) than for Caucasians (0.277+/-0.008). After RMR (I O2/min) was adjusted for LBM, an even larger difference (-12%) persisted for African-Americans (0.250+/-0.008) compared to Caucasians (0.281+/-0.008). Predicted RMR (kJ/d) for the African-Americans was the same as measured RMR, whereas Caucasian women expended about 13% more energy than predicted. When controlling for LBM, the partial correlation between VO2max and RMR was r=0.51 when VO2max was expressed as I/min, and r=0.56 when VO2max was expressed as ml O2/kg/min, both highly significant (P < 0.000).
The lower prevalence of obesity in Caucasian women may be due in part to a higher RMR as well as an under estimation of RMR in weight control therapy. Fitness level (VO2max) as well as LBM are significant predictors of RMR for both races.
比较非裔美国绝经前女性（n = 25）和白人绝经前女性（n = 22）的静息代谢率（RMR）。这些女性年龄为35±1岁（均值±标准误），均处于肥胖状态（体重95.2±2.9 kg，体重指数（BMI）= 34.7±0.9，体脂百分比 = 45.2±0.9），缺乏运动，且无会影响心率或RMR的代谢紊乱或药物治疗情况。
通过间接测热法测量RMR和呼吸交换率（RER），通过体积描记法测量身体成分，测量最大有氧能力（VO₂max）和围度。
采用学生t检验或协方差分析（ANCOVA）进行组间均值比较，协方差分析用于控制体重和去脂体重（LBM）的个体差异。显著性水平设定为P < 0.05。两组在年龄、身高、体重、BMI、体脂百分比、脂肪量、RER、VO₂max、静息心率、最大心率；或胸围、腰围、臀围、上臂围、大腿围或小腿围方面均无显著差异。在对体重进行调整后，非裔美国人的RMR（升氧/分钟）（0.254±0.007）显著低于白人（0.277±0.008）（低9%）。在对RMR（升氧/分钟）进行LBM调整后，非裔美国人（0.250±0.008）与白人（0.281±0.008）相比，差异甚至更大（-12%）。非裔美国人的预测RMR（千焦/天）与实测RMR相同，而白人女性消耗的能量比预测值多约13%。在控制LBM时，当VO₂max以升/分钟表示时，VO₂max与RMR之间的偏相关系数r = 0.51，当VO₂max以毫升氧/千克/分钟表示时，r = 0.56，两者均高度显著（P < 0.000）。
白人女性肥胖患病率较低可能部分归因于较高的RMR以及在体重控制治疗中对RMR的低估。身体适应能力水平（VO₂max）以及LBM是两个种族RMR的重要预测指标。
