Improving Functional Capacity in Fontan Patients Through Inspiratory Muscle Training

Subjects will be provided with noseclips and a threshold impedance device set to 40% of their measured maximal inspiratory pressure and will be trained on using the device. Specifically, subjects will be instructed to breathe through the inspiratory muscle training device while wearing noseclips at a rate of 12 to 16 breaths per minute for 30 minutes a day, 5 days a week for 12 consecutive weeks. Each subject will be provided a customized schedule for increasing resistance by 2 cm H2O every 2 weeks to a maximum resistance of 41 cm H2O.