Efficacy and Safety of the Physical Activity Program in Women With Post-menopausal Osteoporosis

Inclusion Criteria: * signed informed consent * post menopausal women aged \>40 years (with or without history of fractures, with or without pharmacological therapy for OP) * lumbar spine or femur T-score ≤-2,5 * functional motor capacity normal or moderately reduced (Short Physical Performance Battery) * sedentary life style (having exercised less than 30 minutes per week in the last 6 months). Exclusion Criteria are: * secondary OP49, impairment of communicative and/or sensorial functions so severe to make impossible understanding or executing trainer's instructions (dementia, aphasia, blindness, deafness); * heart failure (NYHA class \>2); * unstable angina, pulmonary disease requiring oxygen therapy; * symptomatic peripheral arteriopathy; * myocardial infarction or hospital admission in the previous 6 months, * symptomatic orthostatic hypotension; * hypertension in poor pharmacologic control (diastolic \>95 mmHg, systolic \>160 mmHg), * previous implant of prosthesis at upper or lower limbs, * relevant neurological condition impairing motor or cognitive function, any other condition that the medical doctor (MD) considers to contraindicate the participation in an exercise program of moderate intensity.