Before (baseline) and after the intervention (6 months) total and abdominal adiposity, lean tissue mass and bone mass density (dual-X-ray-absorptiometry), abdominal visceral and hepatic adiposity (magnetic resonance imaging), and blood insulin, glucose, C-reactive protein, alanine aminotransferase, aspartate aminotransferase, gamma-glutamil transpeptidase and lipid profile will be measured. Furthermore, cardiorespiratory fitness (treadmill test) and blood pressure will be measured before and after the intervention. Changes (6 months - baseline) in dietary habits will be estimated by using two repeated 24h recalls and food frequency questionnaires and changes (6 months - baseline) in physical activity by accelerometry.