The inspiratory muscle training (IMT) is a feasible and safe strategy for patients and athletes, your goal is to recondition the respiratory muscles, providing optimization of lung capacity, either for high performance sport as to support metabolic wear caused by illness. It is generally agreed the positive impact of the application of a TMI Protocol on maximal inspiratory pressure (MIP), this benefit encourages individuals sick since weaning from mechanical ventilation (MV), to the optimization of physical performance in cardiac and / or pulmonary rehabilitation. The TMI is based on the principles: the burden imposed on the muscle; the specificity of training; the reversibility of the gain and muscle atrophy.

This prospective double-blind (patient and evaluator) randomised controlled trial compared the efficacy of inspiratory muscle training and inspiratory muscle training. The study protocol for this trial was described elsewhere. This study was conducted in accordance with Consolidated Standards of Reporting Trials recommendations. The trial was performed at the Roberto Santos General Hospital in Salvador, Bahia, Brazil. This study was approved by the institutional hospital ethics committee (approval reference number 03/2014). Before enrolment, written informed consent was obtained from participants or their legal guardians.

Inclusion Criteria:

• Admission to the hospital ward;
• At least two of the following risk factors for prolonged hospitalization: two or more comorbidities; sepsis; liver, lung, or kidney diseases; neoplasia; mechanical ventilation; and use of vasopressor or dialysis therapy.

Exclusion Criteria:

• Patients with a cognitive disability that made them unable to perform the respiratory training;
• Uncontrolled cardiac arrhythmias;
• Circulatory shock;
• Acute ischemic heart disease;
• acute respiratory failure (characterised by a partial pressure of arterial oxygen < 60 mmHg or a partial pressure of arterial carbon dioxide > 50 mmHg);
• neuromuscular disease or myopathies;
• diaphragmatic paresis or paralysis were excluded from the protocol.