Indexed on: 19 Oct '16Published on: 19 Oct '16Published in: The Journal of clinical endocrinology and metabolism
A common concern when using low-calorie diets as a treatment for obesity is the reduction in fat-free mass, mostly muscular mass that occurs together with the fat mass loss, and the best methodologies to evaluate body composition changes.To evaluate the very low-calorie-ketogenic (VLCK) diet-induced changes in body composition of obese patients and to compare three different methodologies employed to evaluate that changes.Twenty obese patients followed a VLCK diet for 4 months. Body composition was performed by dual-energy X-ray absorptiometry (DXA), multifrequency bioelectrical impedance (MF-BIA) and air displacement plethysmography (ADP) techniques. Muscular strength was also assessed. Measurements were performed at four points matched with the ketotic phases (basal, maximum ketosis, ketosis declining and out of ketosis).After 4-months the VLCK diet induced a -20.2±4.5 kg weight loss, at expenses of reductions in fat mass (FM) of -16.5 ± 5.1 kg (DXA), -18.2 ± 5.8 kg (MF-BIA), and -17.7 ± 9.9 kg (ADP). A significant decrease was also observed in the visceral FM. The mild but significant reduction in fat-free mass occurred at maximum ketosis mainly due to changes in the total body water and was recovered thereafter. No changes in muscle strength were observed. A strong correlation was evidenced between the three methods of body composition.The VLCK diet-induced weight loss was mainly at the expense of FM and visceral mass, preserving muscle mass and strength. From the three employed body composition techniques, the multifrequency bioelectrical impedance seems more convenient in the clinical setting.
Indexed on: 22 Jun '18
Published on: 22 Jun '18 in Journal of strength and conditioning research / National Strength & Conditioning Association