Many patients with congenital heart disease do not meet current public health guidelines to participate in moderate-to-vigorous physical activity for ≥60 minutes per day. They are less fit than their healthy peers. We hypothesized that exercise training would increase cardiopulmonary fitness and daily physical activity in these patients. We therefore assessed effects of an exercise training program on cardiopulmonary fitness and daily physical activity in patients with corrected tetralogy of Fallot (ToF) or Fontan circulation.

In a multicenter prospective controlled trial, patients with ToF or Fontan circulation (age 10-25 years) were randomized, 56 patients to the exercise group and 37 to the control group. The exercise group participated in a 12-week standardized aerobic exercise training program. The control group continued lifestyle as usual. Cardiopulmonary exercise testing and activity measurements were performed before and after 12 weeks.

Peak oxygen uptake increased in the exercise group by 5.0% (1.7 ± 4.2 mL/kg per minute; P = .011) but not in the control group (0.9 ± 5.2 mL/kg per minute; P = not significant). Workload increased significantly in the exercise group compared with the control group (6.9 ± 11.8 vs 0.8 ± 13.9 W; P = .047). Subgroup analysis showed a significant increase in pre-to-post peak oxygen uptake in the exercise group of ToF patients but not in the exercise group of Fontan patients.

Percentage of measured time spent in moderate-to-vigorous activity at baseline was 13.6% ± 8.6%, which did not significantly change after training.

Aerobic exercise training improved cardiopulmonary fitness in patients with ToF but not in patients with Fontan circulation. Exercise training did not change daily physical activity.