Fifty Men, 3510 Marathons, Cardiac Risk Factors, and Coronary Artery Calcium Scores An American group has examined vascular seals in the coronious vessels of male marathon runners as it often occurs that such athlete have vascular conciliations although they are physically very active. Only runners were included in the study, which has run at least one marathon every year for 25 years. 51 men were included with an average age of around 60 years ago the total 3'510 marathons have run.It showed that the runners with more calcifications were older, later started in life with the run, older than they ran the first marathon and the runners with more calcifications were sooner and rather showed an increased cholesterol. The bottom line is the vascular conciliation rather on cardiovascular risk factors and not to many marathons or a lot of running training.
Thus, extensive endurance training with competitions is not associated with increased cardiovascular risk. The interesting evaluation can be found under https://pubmed.ncbi.nlm.nih.gov/28719492/