Participants will participate in a remote, app-enabled exercise program consisting of strength and aerobic exercises for four to twelve weeks. They will perform the exercises 3-5 times a week at home guided by exercise videos in the app. The exercise sessions will increase in frequency throughout the training regimen. The videos will include athletes demonstrating how to perform each exercise safely, and provide tips for optimal form and breathing. Participants will wear wearable fitness trackers and monitor their heart rates during exercise sessions.

The participant will either begin at the easiest variation of each strength exercise (level A), or will be placed at a specific level for each strength exercise based on their assessment with physical therapy. Participants can progress to the next level of difficulty of a specific strength exercise based on their rating of perceived exertion (RPE) with the opportunity to move to the next level if they have RPE score of 6 or less and if their heart rates are at goal. Each participant will be provided with heart rate ranges based on the heart rate reserve (HRR) method using their baseline resting and peak heart rates obtained during their cardiopulmonary exercise testing (CPET) or percent predicted heart rate based on age if CPET is not available. HRR goals will be set individually for patients and adjusted per protocol to guide effort.

The Pediatric Cardiac Quality of Life Inventory generates 3 scores (total, disease impact subscale, and psychosocial impact subscale). Each subscale has a maximum of 50 points and their sums yields the total score. Higher scores indicate better perceived health-related quality of life.