Running in Marathons Could Lead to Short-Term Kidney Injury

A new study led by Yale University revealed that the physical stress of running in a marathon could cause a short-term kidney damage that typically lasts for two days.

The study, published in the American Journal of Kidney Diseases, showed that marathon runners could suffer from Stage 1 Acute Kidney Injury (AKI), a condition in which the kidneys fail to filter waste from the blood, soon after their race.

"The kidney responds to the physical stress of marathon running as if it's injured, in a way that's similar to what happens in hospitalized patients when the kidney is affected by medical and surgical complications," said Chirag Parikh, M.D, a professor of medicine and lead investigator of the study, in a press release.

For the study, the researchers collected blood and urine samples from a small group of participants in the 2015 Hartford Marathon. The samples were collected before and after the 26.2 mile event. The researchers used this sample to search for variety of markers of kidney injury, including serum creatinine levels, kidney cells on microscopy and proteins in urine.

The researchers found that about 82 percent of the participants developed Stage 1 Acute Kidney Injury soon after the race. However, the condition of the participants' kidneys improved within two days after the race. The researchers noted that there are several possible causes of marathon-related kidney damage. The rise in core body temperature, dehydration and decreased blood flow to the kidneys that occur during the marathon could all cause kidney damage,

This is not the first time that strenuous physical activity is linked with acute kidney damage. Past studies have shown that vigorous activities, such as mine work, harvesting sugarcane and military training in warm climates can damage the kidneys.

With their findings, the researchers noted that more research is necessary to further understand how different organs inside the body respond to marathon-related stress, especially now that marathons are becoming more popular.