Heart surgery procedures are still widely used worldwide for the treatment of patients with heart problems, and rates of complications in the postoperative period related to them remain high. In these patients, physical conditioning programs result in improved functional capacity, and reducing the heart rate and systolic blood pressure. The inspiratory muscle training is also emerging as a valuable strategy in the treatment of cardiac patients. The study of the interaction between cardiac rehabilitation and high intensity IMT about these changes is not yet understood in this population. The aim of this study is to assess the effects of inspiratory muscle training high intensity associated with cardiac rehabilitation exercise performance of patients in the postoperative period of CABG surgery.

It is a controlled, randomized clinical trial in which patients were randomly assigned randomly after referral to cardiac rehabilitation: Group 1 IMT-HI, group 2 - IMT-HI control. The evaluator of outcomes is blinded as to groups. The study protocol lasts 36 sessions for both groups. The group 1 patients performs cardiac rehabilitation protocol for 40 minutes with cardio and stretching and also inspiratory muscle training protocol of high intensity with 50% load increase in maximal inspiratory pressure during the first two weeks, 60% of MIP in third and fourth week, 70% of MIP in the fifth and sixth week and 80% MIP in the seventh and eighth week. The group 2 patients only perform the cardiac rehabilitation protocol for 40 minutes with aerobic exercise and stretching.

Inclusion Criteria:

• Patients in the postoperative period of elective CABG
• Between the fourteenth and the thirtieth day after surgery
• Between 30 and 70 years old

Exclusion Criteria:

• Decompensated heart failure
• Unstable angina
• Moderate respiratory disease severe
• Active infectious disease or fever
• Disabling peripheral vascular disease
• Unstable ventricular arrhythmias
• Use of cardiac pacemaker.