Effects of diet and physical activity interventions on weight loss and cardiometabolic risk factors in severely obese adults: a randomized trial - Goodpaster, B H; Delany, J P; Otto, A D; Kuller, L; Vockley, J; South-Paul, J E; Thomas, S B; Brown, J; McTigue, K; Hames, K C; Lang, W; Jakicic, J M (JAMA, 2010)