Exercise Training Strategies for Children With Repaired Tetralogy of Fallot

The investigators will explore the feasibility and safety of two exercise interventions delivered both in the hospital and in participants' homes. Preteens and adolescents who have had repaired Tetralogy of Fallot (TOF), will be grouped by age and randomly assigned to either an aerobic or strength training exercise program supervised for 12 weeks. An exploratory aim of this study will be to examine changes in fitness level, muscle strength, muscle oxygen extraction and quality of life after the intervention, and compare these measures between groups. At the end of the study, participants and parents will be interviewed to assess their satisfaction and ideas for improvements in the program.

While adult cardiac rehabilitation (CR) is an established clinical practice, the conceptualization, design and utility of pediatric CR programs have been poorly studied. Particular challenges for children with heart disease include uncertainties regarding physical activity restrictions imposed by clinicians and overprotection by caregivers. These challenges may lead to poor lifestyle and deconditioning, resulting in increased health risks associated with inactivity, such as adiposity, and reduced perceived general health and quality of life. Preliminary studies have shown therapeutic benefits of physical exercise as an add-on therapy in an effort to improve patients' functional outcome after cardiac surgery 1; however, delivery of these programs has been variable, and it is not clear whether a combined program of facility and home-based exercise would yield higher patient adherence for children. The investigators hypothesize that a supervised exercise training program delivered both in the hospital and in participants' homes will be acceptable and feasible for children with repaired Tetralogy of Fallot (TOF). The investigators will conduct a pilot trial over 1 year in which the investigators will randomize 20 participants to either aerobic exercise only or a combined aerobic and strength training program for 12 weeks. The investigators will conduct qualitative interviews to understand intervention acceptability. Results will support a larger definitive study aimed at determining efficacy.

Eligibility Criteria:
Inclusion Criteria:

* Boys and girls ages 10 to 17 years with repaired Tetralogy of Fallot, currently followed at The Hospital for Sick Children, Toronto, Ontario
* Participant fluent in English

Exclusion Criteria:

* Moderate-to-severe ventricular dysfunction at the latest echocardiogram (defined as the qualitative grade given on the echocardiogram done closest to the intervention)
* Previous history of or documented frequent premature atrial or ventricular contractions or runs or associated tachycardia at the latest exercise test
* Reside outside 50km radius from SickKids or \>1hour travel distance to SickKids
* Lack of internet and computer/laptop access
* Skeletal muscle or orthopedic pathologies
* Neurodevelopmental delay that would preclude participation in an exercise program
* History of syncope with exercise
* Planned surgery requiring admission to intensive care unit during the study intervention