Countless marathons take place worldwide every year. Iam_Chihang/CC FLICKR

At 28 years old, Ryan Shay was an elite long-distance runner. He was among the many competitors fighting for a spot to represent the American team in the marathon event at the 2008 Beijing Olympics. Little did he know that qualifying run was going to be his last. Five and a half miles into the race, the athlete collapsed in Central Park. He was rushed to Lennox Hill Hospital, but, having suffered from heart failure, his life could not be saved. It’s stories like these that raise the question: are marathons doing more harm than good?

The good




Running has a long history of benefits to human health and physiology. One of its most well-known effects is on the cardiovascular system. Marathon running has been shown to lower one’s risk of fatal coronary disease.

Direct correlations have also been found between running and life expectancy. Several studies have shown that runners experience an increase in life expectancy compared to non-runners.

According to Professor Jack Goodman from the U of T Faculty of Kinesiology and Physical Education, there are many benefits, both physiological and psychological, to running. “There’s clear health benefits from mental health [like] lower rates of depression [and] greater indices of quality of life,” he told The Varsity.

“Cardiovascular health improves. The risk for chronic diseases like hypertension and heart disease and certain types of cancers… are lower, for both men and women. There are physiological improvements in vessel function, heart function, [and] your muscles adapt and become more efficient,” he said.

The bad

Despite the innumerable health benefits to running, recent studies have released some conflicting results. A study published in Heart showed that excessive exercise for long periods of time can undo its health benefits.

According to CBS News, “exercise… lasting longer than one to two hours can overload the heart.” Over many years, this could lead to thickening of the heart tissue, which in turn raises the risk of developing an irregular heartbeat and sudden cardiac death.

Marathon running can also have negative effects on the blood vessels. “There’s a recent study that has shown that the vessels that supply their heart — the coronary vessels — they may actually have a little bit more calcium in them than average, [and] calcium in a blood vessel isn’t a great thing because it’s involved in the process that helps clog the arteries up,” Goodman said.

Recent evidence may also indicate a correlation between long distance running and cardiac scarring. Goodman and his colleagues are currently studying this correlation in middle-aged long-distance runners and triathletes.

“Out of about 85 — close to 100 — people that we’ve done, a small percentage do in fact show scarring on the heart muscle and fibrosis,” he said. While direct evidence has not clearly linked fibrosis, or scarring, with exercise, there is evidence indicating its presence in runners.

The cause

At first glance, it may seem like endurance activity is the cause of death in many athletes. But according to Goodman, exercise is merely a trigger of an underlying heart condition.

“In younger individuals, typically less than 40, a common cause of sudden death is a problem with their heart muscle that’s undetected and is likely hereditarily driven… Their heart muscle, even though it’s healthy on first appearance… they’re not really growing and maturing properly, and they’re very vulnerable to lethal arrhythmias,” he explained.

“In other words, people with healthy heart[s] don’t die of a marathon,” Goodman said. He pointed to the well-known example of Ryan Shay. “It turns out that his heart wasn’t really healthy. It had a problem in the way [his] cells reproduce and he was vulnerable to a really bad arrhythmia.”

The verdict

While there is evidence of the benefits to physical exercise, proof of the dangers of marathon running have yet to be found. Although stories of athletes dying during marathons can come as a shock, scientifically, there is no cause for concern.

Goodman noted that more lives are saved by having marathons. “We save more lives from motor vehicle accidents by closing roads off to run marathons than [we have] people dying of marathons… that’s how rare it is.”

Long-distance running promotes good health and, with proper training, it brings little to no adverse effects. From what we know, marathon running can increase your life expectancy, and it sure won’t cut it short.

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