The meaning of physical activity for maintenance of a healthy life, normal growth and development of children and adolescents is well known. A regular sport training causes favourable functional changes including improvement in cardiopulmonary or metabolic status. Despite these benefits, vigorous physical exertion may trigger mechanisms leading to sudden death in athletes with unrecognized cardiac disorders. That’s why the regular cardiovascular screening in all young competitive athletes in needed. Complete medical examination of young athletes (including a medical personal and family history and physical examination) should give information about functional status of cardiovascular system. Physical examination should include auscultation in supine, seated and upright position, palpation of peripheral pulses, accurate measurement of blood pressure and looking for findings of Marfan syndrome. Physical examination may reveal signs of cardiovascular effects of adaptation to long‑term sport activity, i.e., enlargement of the heart (increase of dimensions, wall thickness and mass of left ventricle) and a slow pulse rate at rest as a result of vagal tone increase.Another target of cardiovascular examination of young athletes is to identify underlying heart disease (especially in aspect of prevention of sudden cardiac death) requiring the extension of diagnostic workup. The main aim of this paper is to give for paediatricians and family doctors some practical information helpful in proper interpretation of physiological, adaptive circulatory changes in relation to long‑term physical activity and identification of cardiac pathologies threatening of sudden death in association with sporting activity.