Last updated: 12-Jul-17
Many of us use ibuprofen during or after races to help with swelling and pain – I like to call it chemical stretching – but a new study by the Stanford University School of Medicine has found that those who take the painkiller while running very long distances double their risk of acute kidney injury.
Acute kidney injury sounds terrifying but is actually quite common in ultra runners because dehydration causes reduced blood flow and a breakdown of muscle tissue. This process releases muscle fibre pieces into the blood. They have a negative effect on the kidneys, but the body adjusts and any damage is usually short-term and resolves itself. However, some extreme athletes have suffered more serious damage and, in the worst case, died. A couple of years ago, a 40-year-old man who took part in the Boulder Ironman died three days later due to kidney failure.
This new study shows that adding ibuprofen into this mix can increase the dangers. What makes the study so unusual is that it was very specifically targeted at ultra runners and was carried out by doctors with direct ultra running experience.
It was led by Grant Lipman, MD, clinical associate professor of emergency medicine at Stanford, director of Stanford Wilderness Medicine, and medical director of RacingThePlanet and Brian Krabak, MD, a sports and rehabilitation medicine specialist at the University of Washington-Seattle.
For the purposes of the study, Lipman and his colleagues conducted a randomised, placebo-controlled, double-blinded test on the use of ibuprofen in ultra marathoners.
There were 89 participants who were then randomly chosen to take either 400 milligrams of ibuprofen or a placebo during a 50-mile section of one of four different seven-day, 155-mile ultramarathons. They couldn’t take ibuprofen for at least 12 hours prior to the 50-mile section of the race.
At the end of the races, the participants went straight to the research area where they were weighed and their electrolyte levels and kidney functioning were looked at.
Rates of kidney injury
Results from the test were startling in that they showed that about 39 of the 89 participants had acute kidney injury at the end of the 50-mile section of the race. Forty-seven percent of the participants took ibuprofen, and 53 percent took the placebo. There was an 18 percent higher rate of kidney injury among those who took the drug, which Lipman said was a higher percentage than he had expected.
So, what does this mean? Should ultra runners stop taking ibuprofen? Lipman didn’t go that far but he did advise caution. “I would generalize to say, yes, caution should be warranted taking ibuprofen during long distance runs or other endurance sports events. But I would not push that caution to the general lay population. This study’s conclusions are for endurance athletes.
Studies show that for most people, this acute kidney injury is usually resolved within a day or two after the race. However, numbers of runners have ended up being hospitalized from renal failure.”
Lipman said that he was taken aback by the results as he had gone into the test assuming that ibuprofen would be safe.
“I felt surprised and a little shocked that it really is as bad for you as we found,” he said. “I feel it’s ironic to preach moderation in extreme sports, but moderation is probably a safe approach. If something hurts, these athletes might want to consider taking acetaminophen instead.”
On an interesting note, he himself has now switched to using an acetaminophen, such as paracetamol/Tylenol, for pain relief and is taking ice baths after racing.
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