Frisard Madlyn I, Greenway Frank L, Delany James P
Pennington Biomedical Research Center, Baton Rouge, LA 70810, USA.
Obes Res. 2005 May;13(5):845-54. doi: 10.1038/oby.2005.97.
To assess the accuracy of body composition measurements by air displacement plethysmography and bioelectrical impedance analysis (BIA) compared with DXA during weight loss.
Fifty-six healthy but overweight participants, 34 women and 22 men (age, 52 +/- 8.6 years; weight, 92.2 +/- 11.6 kg; BMI, 33.3 +/- 2.9 kg/m(2)) were studied in an outpatient setting before and after 6 months of weight loss (weight loss, 5.6 +/- 5.5 kg). Subjects were excluded if they had initiated a new drug therapy within 30 days of randomization, were in a weight loss program, or took a weight loss drug within 90 days of randomization. Subjects were randomly assigned either to a self-help program, consisting of two 20-minute sessions with a nutritionist and provision of printed materials and other self-help resources, or to attendance at meetings of a commercial program (Weight Watchers). Body composition was examined by each of the methods before and after weight loss.
BIA (42.4 +/- 5.8%) underestimated percentage fat, whereas the BodPod (Siri = 51.7 +/- 6.9%; Brozek = 48.5 +/- 6.5%) overestimated percentage fat compared with DXA (46.1 +/- 7.9%) before weight loss. Correlation coefficients for detecting changes in body composition between DXA and the other methods were relatively high, with Brozek Deltafat mass (FM; r(2) = 0.63), Siri FM (r(2) = 0.65), tetrapolar BIA percentage fat (r(2) = 0.57), and Tanita FM (r(2) = 0.61) being the highest.
In conclusion, all of the methods were relatively accurate for assessing body composition compared with DXA, although there were biases. Furthermore, each of the methods was sensitive enough to detect changes with weight loss.
评估在体重减轻期间，与双能X线吸收法（DXA）相比，空气置换体积描记法和生物电阻抗分析（BIA）测量身体成分的准确性。
56名健康但超重的参与者，34名女性和22名男性（年龄，52±8.6岁；体重，92.2±11.6千克；体重指数，33.3±2.9千克/平方米）在门诊环境中接受了6个月体重减轻前后的研究（体重减轻，5.6±5.5千克）。如果受试者在随机分组后30天内开始新的药物治疗、参加了减肥计划或在随机分组后90天内服用了减肥药物，则将其排除。受试者被随机分配到一个自助计划组，该计划包括与营养师进行两次20分钟的会面，并提供印刷材料和其他自助资源，或者参加一个商业计划（慧俪轻体）的会议。在体重减轻前后，通过每种方法检查身体成分。
与减肥前的DXA（46.1±7.9%）相比BIA（42.4±5.8%）低估了脂肪百分比，而体成分测量仪（Siri法=51.7±6.9%；Brozek法=48.5±6.5%）高估了脂肪百分比。DXA与其他方法之间检测身体成分变化的相关系数相对较高，其中Brozek法的去脂体重（FM；r²=0.63）、Siri法的FM（r²=0.65）、四极BIA脂肪百分比（r²=0.57）和百利达FM（r²=0.61）最高。
总之，与DXA相比，所有方法在评估身体成分方面都相对准确，尽管存在偏差。此外，每种方法都足够灵敏，能够检测出体重减轻带来的变化。
