The benefits of maintaining a physically active lifestyle in children and adolescents go beyond physical health, extending to improvements in social, mental, and emotional well-being. Focus is shifting from exercise restriction to exercise advocacy not only in the general population but also in patients with congenital and other types of heart disease. Pediatricians must be knowledgeable about the latest recommendations and debates regarding the preparticipation physical evaluation and exercise recommendations for a diverse population. This article provides a brief summary of exercise physiology and a review of worrisome symptoms with exercise. We then discuss preparticipation screening evaluations and review activity recommendations in children with heart disease with the goal of keeping as many young patients as active as possible for long-term cardiovascular health.