Diaphragm paralysis is a possible complication of cardiac surgery. The spontaneous recovery of the diaphragm mobility is slow and partial or absent in most cases. We hypothesize that a program of diaphragm muscle training by means of the Threshold variable resistance device could improve the rate of complete diaphragm mobility recovery in a shorter time period. Patient with post-cardiosurgical diaphragm paralysis will be random assigned to the specific training protocol or to a generic non-training physical activity.

Inclusion criteria: All consecutive patients aged from 18 to 80 years old with RX-defined diaphragm paralysis post a major cardiosurgery intervention such as coronary bypass, valve substitution or both.

Exclusion criteria: Acute cardiac failure, COPD, chronic respiratory failure with indication to home oxygen therapy, neuromuscular diseases.

Outcome measures: MIP, MEP, diaphragm function recovery assessed by chest X-ray, lung function tests.

Inclusion Criteria:

• post-cardiosurgical diaphragmatic paralysis recent cardiosurgical intervention for by-pass and/or valve replacement

Exclusion Criteria:

• heart failure
• COPD
• neuromuscular disease