For a study, researchers sought to determine whether fitness training was beneficial for children and adolescents born with congenital cardiac disease. Researchers conducted an exhaustive search using the following information resources: PubMed, CINAHL, EMBASE, Web of Science, and SportDiscus. They looked at children and adolescents with congenital cardiac disease and participated in randomized controlled trials that compared an exercise intervention with a control group that did not exercise. The goal was to determine whether or not the exercise intervention was safe and effective. A descriptive analysis of all of the included trials was carried out. There were 9 articles from 6 studies, with 642 individuals, all of whom had different diseases and differing degrees of disease severity. There were no adverse events reported that were connected to the exercise programs. Several favorable changes to clinically important fitness measures were reported in the papers. In 3 of the 4 trials in which it was measured, exercise capacity increased due to exercise training. In 3 out of 4 trials, there was an increase in participants’ cardiorespiratory fitness. In 1 out of the 2 studies, neuromuscular fitness improved. In 2 out of 2 studies, physiological and metabolic parameters were shown to have improved. At the same time, adverse changes to numerous clinically significant measurements (such as muscular oxygenation and cardiac measures) were not found to have occurred. In 1 out of the 3 studies, there was an increase in physical activity. There was not a single publication that discussed any changes in body composition measurements. The outcomes were highly variable, and there was little agreement on the metrics or assessment methodologies used. If a kid or adolescent with congenital heart disease had been properly screened by their medical team, exercise training looked safe and effective for improving the patient’s physical fitness. On the other hand, the evidence supporting these findings had a low to moderate level of assurance.