 The aim is to evaluate the effectiveness of an intervention based on a program of physical activity and diet coordinated between primary care teams PCT and Mental Health Centres MHC to modify the weekly physical activity PA amount, body mass index BMI and waist circumference in patients with severe mental disorder diagnoses. To assess changes in cardiovascular risk, quality of life and lifestyles, secondarily. Methods: A randomized clinical trial with a control group, of one year of follow-up, carried out in four MHC Barcelona and Santa Coloma, and PCT of reference. The investigators studied patients aged 18 - 65 years old, diagnosed with schizophrenia, schizoaffective or bipolar disorder, with antipsychotic medication and a low level of PA. 240 patients will be selected in each group difference to be detected in the BMI: 1.89 kgm2; common SD: 6.2, 30 loss. Intervention: group educational PA program basically walking of 24 sessions over 12 weeks, and diet 8 sessions in the first 8 weeks by nurses and specialists in PA. Key measurements: level of PA IPAQ questionnaire, physical examinations: BMI, waist circumference, blood pressure, cardiovascular risk, quality of life SF-36, smoking habits, dietary habits PREDIMED questionnaire, analytical parameters: cholesterol , triglycerides, blood glucose. Evaluations will be masked and conducted at 0, 3, 6 and 12 months. Analysis of variance for repeated measures to adjust for differences attributable to the effect of the intervention for potential confounders: pharmacological treatment, care level of intervention and mental state. 