CARDIOVASCULAR

Full list of author information is available at the end of the articleBackground There is an increasing participation in long-distance running events; there is clear evidence that regular phys-ical activity reduces cardiovascular risk [1-3]. Still, it is unknown if the intensity of physical activity and the beneficial effects correlate linearly and whether Mara-thon running is dangerous for the cardiovascular system [4]. However, some studies on Marathon running raised concerns of acute and sustained myocardial injury of the left and the right ventricle assessed by cardiac biomarkers and echocardiography [5,6]. Other studies could not confirm exercise-induced myocardial damage [7,8]. Several studies have been published with the aim of evaluation of left and right ventricular function in ath-letes with different forms of training including endur-ance recently. These studies were focused only on young and elite athletes [9,10]. Up to date, there are rare data about the cardiac mechanics at resting condition of well endurance-trained amateur athletes with a broad range of age. Two-dimensional strain is a new Doppler independent approach for calculation of strain, strain rate, tissue vel-ocity, and displacement. It is based on speckle trackin