How many run the Boston Marathon? Is it 800? Thousands run in the Chicago Marathon.
How many of the, let us say, 800 are on the verge of heart damage or into that region? Virtually all of them. A few go into the region so far that they suffer a heart attack and die.
Virtually all of the 800 hearts in the marathon suffer damage ranging from mild to worse. This is fully documented by the study of heart muscle enzymes and other markers. Here is an article from Men’s Health that covers some of the damage from the huge surge of inflammation that occurs when you run a marathon. Even training, which most marathoners fail to do, offers incomplete protection.
Might I add that the mortality statistics are way off. Calculating the death rate over the thousands of participants understates the risk by perhaps a factor of 4 to 8. That is because most marathoners do multiple events each year. So, they are not different people running in these events. Many of them are the same person.
If a “typical” marathoner runs 8 events a year, then the death rate is about 8 times the rate that is calculated as though they are different individuals. And then there are those who die in training, or injure their hearts and drop out. They are damaged, but do not show up in the death statistics.
Alberto Salazar, one of the best marathoners, did not die but he is damaged beyond repair. Fortunately, for less serious marathoners, the damage can be repaired but it takes months following the marathon. How do we count the post marathon deaths if a heart not yet fully repaired quits under some other stress?
When you realize that all of the hundreds or thousands running past will suffer some heart damage, you see a marathon in a different way. It presents a new vision to see the marathon as a kind of massive participation in a willing form of heart damage, a few of which will end in death.
The Boston Globe published an article, dated April 17, 2006, that reported on tests made on runners completing the Boston Marathon. The bottom line of the article was that runners who run at least 45 miles per week for several months before the marathon don't have problems. Runners who run less than that may have heart problems.