The effects of diet- and diet plus exercise-induced weight loss on basal metabolic rate and acylated ghrelin in grade 1 obese subjects

André L Lopes,¹ Ana Paula T Fayh,^2,3 Luisa G de Souza Campos,⁴ Bruno C Teixeira,¹ Randhall B Kreismann Carteri,¹ Jerri L Ribeiro,⁴ Rogério Friedman,² Álvaro Reischak-Oliveira<sup>1

1</sup>Exercise Research Laboratory, School of Physical Education, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil; ²Endocrine Unit, Hospital de Clínicas de Porto Alegre, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil; ³Health Sciences College of Trairi, Universidade Federal do Rio Grande do Norte, Santa Cruz, RN, Brazil; ⁴Centro Universitário Metodista – IPA, Porto Alegre, RS, Brazil

Background: Diet and exercise are often prescribed as primary intervention regarding obesity-related disorders. Additionally, recent studies have shown beneficial effects of weight loss through diet and exercise in ghrelin concentrations in obese subjects. The aim of this study was to evaluate the effects of a 5% weight loss on lipid profile, resting metabolic rate (RMR), and acylated ghrelin (AG) using two different methods of intervention (diet or diet plus exercise).
Materials and methods: Eighteen subjects (twelve women and six men) aged 20–40 years with a body mass index of 30–34.9 kg/m² (grade 1 obesity) were randomized into two intervention groups: diet (n=9) or diet plus exercise (n=9). Both groups underwent treatment until 5% of the initial body weight was lost. At baseline and upon completion, RMR and AG were analyzed.
Results: Both groups showed a significant decrease in body fat percentage and fat mass. The diet-plus-exercise group showed a decrease in AG (pre: 54.4±25.3 pg/mL and post: 33.2±19.1 pg/mL) and an increase in RMR (pre: 1,363±379 kcal/day, post: 1,633±223 kcal/day).
Conclusion: These data suggest that diet plus exercise induced weight loss and had beneficial effects on AG concentration and RMR, essential factors to ensure the benefits of a weight-loss program.

Keywords: exercise therapy, diet, energy regulation, obesity, hormones