Rapid Weight Loss Tanks Metabolism? The TBL Study
Thanks to Yoni Freedhoff of Weighty Matters blog for providing me with the full text of this one. Check out his take on the results. Update 11/11/13: Full text now available free HERE . Context: An important goal during weight loss is to maximize fat loss while preserving metabolically active fat-free mass (FFM). Massive weight loss typically results in substantial loss of FFM potentially slowing metabolic rate. Objective: Our objective was to determine whether a weight loss program consisting of diet restriction and vigorous exercise helped to preserve FFM and maintain resting metabolic rate (RMR). Participants and Intervention: We measured body composition by dual-energy x-ray absorptiometry, RMR by indirect calorimetry, and total energy expenditure by doubly labeled water at baseline (n = 16), wk 6 (n = 11), and wk 30 (n = 16). Results: At baseline, participants were severely obese (×± sd; body mass index 49.4 ± 9.4 kg/m 2 ) with 49 ± 5% body fat. At wk 30,