Congenital heart disease (CHD), the most common birth defect, is present in nearly 1% of the population. CHD patients are associated with intense resource utilization and premature death in adulthood. The risk of premature death is linked with reduced exercise capacity, a finding consistently noted in youth with CHD. Reduced exercise capacity in this population has also been associated with reduce physical activity and health-related quality of life. Cardiac rehabilitation (CR) in adults with acquired heart disease is an established secondary prevention strategy that improves exercise capacity. The investigators propose a prospective clinical trial of a home-based high intensity interval training (HIIT) program using a novel telemedicine-equipped video game-linked cycle ergometer (MedBIKE™) for 10 to 18 year olds with repaired moderate-complex CHD. The pilot study with the MedBIKE has shown promising results. The investigators now seek to study the efficacy of this program in a broader CHD population.