title: Effect of endurance training on Q-T interval and cardiac electrical stability in boys aged 10 to 14. Ventricular arrhythmias in trained boys.
abstract: In 30 highly trained boys aged 10-14 the prevalence of ventricular ectopic beats and Q-T interval duration were studied. In trained boys ECG Holter monitoring showed a higher even though not significantly different prevalence of ventricular arrhythmias than in 30 age-matched untrained controls. Ventricular ectopy was on the contrary lower than in a group of 30 adult athletes. Q-T corrected (Q-Tc) interval in the trained boys was longer than in the sedentary controls (p less than 0.001), while it was as long as in the adult athletes. No correlation was found between the degree of severity of ventricular ectopic beats and Q-Tc interval duration, heart rate or echocardiographic dimensional and functional findings. The clinical and prognostic importance of complex ventricular arrhythmias detected in healthy athletes remains to be elucidated.
mesh_terms: D000293:Adolescent; D000328:Adult; D001145:Arrhythmias, Cardiac / Q000209:etiology*; D001642:Bicycling; D002648:Child; D004562:Electrocardiography; D006801:Humans; D008133:Long QT Syndrome / Q000209:etiology*; D008297:Male; D008991:Monitoring, Physiologic; D010806:Physical Education and Training; D010807:Physical Endurance; D012420:Running