Prevalence and nature of cardiac arrhythmias in apparently normal well-trained runners.
Sixty well-conditioned runners were evaluated for arrhythmias by Holter monitor during both a distance run and a maximal treadmill test. Twenty-seven percent of subjects had ventricular arrhythmias during treadmill testing, only 3% having grades higher than just an occasional isolated premature ventricular complex (PVC), compared with 60% during the monitored run, of which ventricular bigeminy occurred in 10%, ventricular couplets in 10%, and multiform PVCs in 5%. Treadmill testing significantly underestimated the frequency and grade of both atrial and ventricular arrhythmias: 57% of subjects who had ventricular arrhythmias while running had none on the treadmill, and 11 of 16 who had ventricular arrhythmias on the treadmill had up to 3 grades higher on the run. The discovery of frequent high-grade atrial and ventricular arrhythmias in subjects considered to be completely fit and healthy suggests that such variations in heart rhythm are a normal phenomenon and no more specific for heart disease or risk than ventricular arrhythmias during maximal treadmill exercise testing.
D000293:Adolescent; D000328:Adult; D000368:Aged; D001145:Arrhythmias, Cardiac / Q000175:diagnosis / Q000453:epidemiology*; D005080:Exercise Test; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D012420:Running