A new study conducted by Dr. Eric Larose, a cardiologist at the University Institute of Cardiology in Quebec, finds the stress of running a marathon causes heart damage, though temporarily. A runner himself, Dr. Larose determined to study whether damage occurs during a long distance run such as a marathon, and whether that damage weighs on future heart health. The study followed 20 marathoners from different levels including training for a first marathon to a few who had run as many as 30. Runners were tested six-to-eight weeks before the marathon, immediately after they crossed the finish line, and three months after the race. Tests included imaging studies of the heart to pinpoint how it reacted to the strain of the marathon; it also measured inflammation and blood flow. After all three stages, the study found levels of an enzyme called troponin were higher immediately after the marathon. Pre-marathon imaging showed the heart functioning at below normal capacity, and not pumping blood as efficiently and struggling to battle inflammation. These factors caused damage to the heart muscle, and more pronounced in those who were less fit.
A three-month follow up showed damage had dissipated, and the heart was functioning properly. Sports, especially in competition, often push athletes to the limits. So it doesn’t come as a surprise that the heart, as well as other body organs and systems, are strained during a 24-to-26 mile run. Of course it’s alarming, but also reassuring that the cardiovascular system recovers and gets ready for the next race.