[The effect of extreme endurance loading on the chronometry of cardiac systole]

1. Extreme long-term endurance loads of great intensity lead during the recovery period to significant changes of the preejection period and Weissler's index. The cause of this change is most probably the reversibly impaired contractility of the heart muscle after fatigue of the left ventricle as a result of a certain degree of overburdening. 2. Systolic time intervals are suitable means for the dynamic follow-up of the performance of the left ventricle in subjects after sports performances.