Inclusion Criteria:  Subjects admitted to ICU Adults ≥15 years IMV requirement >48 hours  Exclusion Criteria:  Neuromuscular disease Psychiatric history (attempted autolysis, schizophrenia, senile dementia or others, who due to their condition are unable to follow simple orders, which could bias the assessment and functional treatment) Limb amputation Pregnancy Cardiorespiratory arrest with severe hypoxic-ischemic brain damage Total dependence prior to hospitalization, according to Barthel index (<20 points); Subject without consenting to participate in the study.