Bio-Electrical Properties of Body Tissues in Obese Women after a Program Composed by Physical Exercises and Nutrition Education

Aims: To identify changes in bioelectrical properties of body tissues in obese women, after a program composed by physical activity and nutrition education. Methods: We studied 24 women, 30 to 50 years old, BMI ≥ 30 kg/m² (obese). The participants were submitted to a 16 weeks program composed by nutrition education (lectures and practical activities, 13 meetings) and physical exercise (walking and resistance exercises, 60 minutes per day, three days per week). Variables investigated: Fat- free mass (FFM) by DEXA; bioelec- trical properties of the tissues by bioimpedance vectorial analysis (BIVA); total body water (TBW) by deuterium dilution (only at the end of the program), serum albumin (by colorimetric meth- od). Main results: On average, FFM was reduced, however, the values presented a great individual variability; some of the participants reduced, others maintained or increased FFM; - TBW was considered within normality; - from BIVA analysis, most of the individuals who reduced the fat-free mass showed a poor hydration status. Putting the albumin, TBW and BIVA analysis together, we can indirectly suppose changes in the ratio of extracellular water/total body water in some of the participants. Conclusions: The combination of different analysis of water balance (BIVA, TBW and serum albumin) gave us an indirect inference that our program was not able to prevent imbalances. These imbalances can give an explanation to the fat-free mass losses.