HIIT in Youth With Congenital Heart Disease (MedBIKE)

This study tests a home-based high-intensity interval training (HIIT) bike program called MedBIKE for children and teenagers with repaired congenital heart disease. The goal is to see if structured, supervised exercise at home can safely improve fitness and quality of life for young people with heart conditions. **You may be eligible if...** - Your child is 10–18 years old - Your child has had surgery to repair a moderate-to-complex congenital heart defect - Your home can fit the MedBIKE equipment - Your child's heart doctor has not restricted exercise **You may NOT be eligible if...** - Your child does not speak English (needed for communication during sessions) - Your child's heart doctor has advised against exercise - Your child has had concerning results on a prior exercise stress test (arrhythmias, abnormal blood pressure, chest pain, or fainting) - Your child has an oxygen level at rest below 85% or needs supplemental oxygen - Your child has moderate-to-severe ventricular dysfunction - Your child has had a heart rhythm problem in the last year - Your child has an unrepaired heart defect Talk to your doctor to see if this trial is right for you.