Cardiometabolic and Fitness Improvements in Obese Girls Who Either Gained or Lost Weight during Treatment.

OBJECTIVE To evaluate the quality of weight change (change in fat mass vs fat-free mass [FFM]), changes in cardiorespiratory fitness (CRF), and frequencies of metabolic risk factors in adolescent females with obesity who either lost or gained weight following lifestyle treatment. STUDY DESIGN Fifty-eight girls (mean age = 13.0 ± 1.6 years; 77% black; mean body mass index = 36.5 ± 4.5 kg/m(2)) completed a 6-month lifestyle intervention combining dietary and behavioral counseling with aerobic and resistance exercise training. We examined baseline to 6-month differences in weight (kg), body composition, CRF, and frequencies of metabolic risk factors between weight loss and weight gain groups. RESULTS In the weight loss group, body weight (-4.50 ± 3.53 kg, P < .001), fat mass (-4.50 ± 2.20 kg, P < .001), and body fat percentage (-2.97% ± 1.45%, P < .001) decreased, and FFM was unchanged at 6 months. In the weight gain group, body weight (4.50 ± 2.20 kg, P < .001), fat mass (1.52 ± 3.16 kg, P < .024), and FFM (2.99 ± 2.45 kg, P < .001) increased, and body fat percentage was unchanged. Both groups improved CRF (P < .05). Frequencies of metabolic risk factors were reduced across all participants after the 6-month treatment. CONCLUSIONS Participation in a weight management program might elicit health improvements in obese adolescent females who increase weight and fat mass, provided that FFM gains are sufficient to negate increases in body fat percentage. TRIAL REGISTRATION ClinicalTrials.gov: NCT00167830.