Wenckebach Phenomenon with Nodal and Ventricular Escape in Marathon Runner

A 27-year-old gendarme non-mmmlasioned officer, 170 cm in height, ran 5 to 10 kilometers a day regularly during 196&1963, and has been running 30 to 60 kilometers per day since for Olympic and Marathon racing training. He has no complaints. His routine check-up revealed, however, certain interesting indications which have given occasion to this report. His family and past history were unremarkable. He has been in good general health. Before running, while resting, all clinical examinations gave normal results, with the exception of alterations in intensity of first heart sound, dysrythmia and bradycardia, all of which disappeared after running and administration of atropine. Physical examination and laboratory findings ( 1 ) before running, (2) after running 40 kilometers within a period of three hours in humid conditions and no sunshine at an altitude of 860 meters above sea level, are as follows: