RESUMO
There is a lack of information about the performance and clinical use of body fat measurements in children and adolescents, particularly in obese people. Objective: the purpose of this study was to compare percentage body fat (%BF) among 3 different methodologies, including hydrostatic weighing (HW), dual energy x-ray absorptiometry (DXA) and air displacement plethysmography (ADP), in obese adolescents. Subjects: A total of 36 obese adolescents were evaluated, which 15 males (16.00 + 0.9 yrs, 105.0 + 10.9 kg, 179.9 + 7.2 cm, 34.9 + 4.4 kg/m2) and 21 females (16.5 + 1.5 yrs, 91.1 + 10.5 kg, 163.6 + 4.2 cm, 34.1 + 3.7 kg/m2). All of them performed HW, total body DXA and ADP. Results: For males, the means of %BF regarding HW, DXA and ADP were 45.7 + 9.0, 42.3 + 5.2 and 35.6 + 7.9, respectively. For females, the means of %BF were 47.7 + 6.8, 50.7 + 4 and 42.4 + 5.3, respectively. No significant difference was found between HW and DXA. In general, the %BF values provided by ADP measurements were lower than other two methods. Conclusion: There was a good agreement between DXA and HW methods, but ADP measurements can underestimate the %BF in obese adolescents.