Tehran University of Medical Sciences Acta Medica Iranica 0044-6025 50 8 2012 08 15 560 564 EN Behzad Farahani Department of Cardiology, Firoozgar Hospital, Tehran University of Medical Science, Tehran, Iran. Mehrshad Poursaeid Esfahani Department of Sport Medicine, Shahid Beheshti Medical University, Tehran, Iran. Mohammad Amin Abbasi Department of Internal Medicine, Shahid Beheshti Medical University, Tehran, Iran. Farhad Moradi Department of Cardiology, Firoozgar Hospital, Tehran University of Medical Science, Tehran, Iran. Ata Abbasi Department of Pathology, Tehran University of Medical Sciences, Tehran, Iran. 2015 09 28 To explore the abnormalities in Iranian athletes' electrocardiogram and find any relation with body fat. 239 international athletes were involved in this cross sectional study. Body-fat percentage and resting 12-lead ECGs were recorded from all participants. Of 239 participant athletes, 212 were male and 27 female. 60% of participants had sinus bradycardia. A total of 84% of the athletes demonstrated at least 1 abnormal ECG finding. Average values for the PR, QRS and QT intervals, P-wave duration and QRS axis were in normal range. Frequencies of various ECG abnormal findings in all athletes were as follows: right axis deviation 4.2%, left ventricular hypertrophy 6.2%, sinus arrhythmia 5.8%, right bundle branch block (RBBB) 24.2% (incomplete RBBB 16.8%, complete RBBB 7.4%), ST elevation 72.5%, prolonged QT interval 1.7%, T inversion 3.1% and Mobitz type I 1.2%. The athletes' ECG response to treadmill stress test was normal with no ischemia or arrhythmia. The means of BMI and body-fat percentage were 24.04 ± 3.5 kg/m² and 9.15 ± 2.12%, respectively. Pearson correlation coefficient between body-fat percentage and ST changes was 0.65 (P=0.008) in anterior leads and 0.198 (P=0.017) in lateral leads. Also, the correlation coefficient between the body fat percentage and right bundle branch block was 0.36 (P=0.013). The results of current study support the inclusion of ECG in athletes' cardiac screening before they engage in vigorous exercises in order to detect the potentially fatal arrhythmias. https://acta.tums.ac.ir/index.php/acta/article/view/3949 https://acta.tums.ac.ir/index.php/acta/article/download/3949/3924