This study's goals were to investigate the use of bioelectrical impedance in obesity and to validate its application in determining human body composition. Eighty-seven adults with a variety of body fat percentages (8.8–59.0%) conducted underwater weighing and bioelectrical impedance measurements (density). According to previously reported regression equations, fat-free mass (FFM) derived from bioelectric impedance and fat-free mass (FFMd) determined from density were compared. All body fat levels had high correlation values (0.94-0.99), however in participants with body fat levels greater than 42%, impedance equations overestimated FFM relative to FFMd. The electrical characteristics of tissues have been documented. Additional descriptions of these characteristics were provided for a wider range of frequencies and a wider variety of tissues, including those that had been damaged or were undergoing a transformation after death. Thomasset carried out the initial research utilizing two subcutaneously implanted needles to detect electrical impedance as an indicator of Total Body Water (TBW).
