AMBULATORY ELECTROCARDIOGRAPHIC FINDINGS IN TOP ATHLETES, ATHLETIC STUDENTS AND CONTROL SUBJECTS

Aim of the present study was to evaluate 24 h electrocardiographic rec ording in 30 top athletes, 30 athletic students and 30 sedentary contr ol subjects. Each group consisted of 15 males and 15 females and were matched for age (about 24 years). Training was not allowed during the recording. Top athletes had the lowest diurnal and nocturnal heart rat e, but the difference between top athletes and athletic students was f ar less pronounced than between athletic students and controls. This m ay indicate that bradycardia reaches a lower limit with moderate degre es of training. Atrioventricular (AV) block II was found in 3 top athl etes and 4 athletic students and in none of the subjects, the longest pause being 2.4 s in both athletic groups. Most episodes occurred duri ng night and nearly all were Mobitz type I, In all cases of AV block I I the QRS complexes were narrow and AV block III did not occur. SA blo ck was found in 3 top athletes, 1 athletic student and 1 control subje ct, the longest pause being 3.1, 2.9 and 1.9 s, respectively. Ventricu lar premature beats were rare in all groups and complex ventricular ar rhythmias were not found. Half of the subjects were in Lown class O, t he other half in Lown class 1. Supraventricular premature beats were a lso scarce and most frequent in top athletes, followed by athletic stu dents and sedentary controls (2.0, 1.0, 0.7 beats/h, respectively).