Daily inspiratory muscle strength and endurance training (IMT) was performed in a 44-year-old patient with idiopathic bilateral diaphragmatic paralysis (BDP) in addition to nocturnal non-invasive ventilation (NIV). After 4 months of training inspiratory muscle function improved satisfactorily whereas phrenic nerve latency remained pathological. Due to the improvement of inspiratory muscle capacity nocturnal NIV could be stopped without inducing nocturnal respiratory insufficiency.