Inclusion Criteria:  PTNB with GA ≤37 weeks In ventilation invasive mechanics With absence of congenital malformations With absence a diagnosis of intracranial hemorrhage That the guardians after being informed, authorized to participate in the research  Exclusion Criteria:  PTNB without a legal companion Who are affected by some unfavorable clinical condition that makes it impossible to change position Children with neuromuscular diseases Tracheostomized