Can you get rhabdo from running?

The short answer is yes, but it’s unlikely, if you train, fuel and hydrate correctly. Rhabdo (short for rhabdomyolysis), a condition that is more often associated with CrossFit athletes and bodybuilders, can sometimes affect ultrarunners also. Here’s what you need to know to protect yourself.

https://www.instagram.com/p/B4CpK3UgJE3/

Rhabdo causes the skeletal muscles to break down and release a toxic substance into the bloodstream, and that can lead to kidney damage. Natalie Shanahan, who represented Canada at the 24-hour World Championships in France in October 2019, had a mild case after completing her first 24-hour race.

Shanahan was racing at Across the Years in 2016-2017. Despite having dealt with an injury in the six weeks leading up to the race, she had a good showing and was pleased with her performance (she ran just over 184 kilometres). It wasn’t until after the race that she noticed the symptoms.

RELATED: A Good Fit: Exploring the Benefits of CrossFit for Runners

https://www.instagram.com/p/BXMXEeVgN-a/

“Immediately after the race I was very swollen throughout my lower body,” Shanahan says. She developed a horrible headache, worse than any she’d ever had. She assumed it was due to dehydration, so she made sure to drink lots of water to recover. Hydrating didn’t help, though, and she decided to take a trip to the hospital.

“I went to emergency and they did blood work,” she says. They told her she had a mild case of rhabdomyolysis. Shanahan is a physical therapist who works with artificial and mechanical heart recipients, and the diagnosis made sense to her. She received three litres of IV fluids and painkillers for her headache. Her creatine kinase (CK) levels were tested, and they were more elevated than they should have been.

https://www.instagram.com/p/B1VB6CBABT_/

“The higher the [CK] number, the more it signifies the muscles have broken down,” she says. “As it gets higher, the kidneys can’t process it. The risk is that the kidneys may shut down.” This is often seen in medical patients who have suffered from heart attacks or other types of organ failure. Their muscles break down and their CK levels elevate drastically.

Shanahan says that it’s natural for muscles to break down while undergoing extreme exertion. “Every runner probably has some element [of muscle breakdown] after long endurance [runs]. Needing treatment is the rarity.”

Dennene Huntley Pangle, winner of the 72-hour event at the most recent Across the Years in Phoenix, also has experience with the condition, which briefly put her in the hospital after returning from the Javelina 100 in 2018. There were no lingering effects–her next race, the 72-hour event at Across the Years 2018-2019, went great. She finished second overall, running a total of 235 miles (379 kilometres).

Shanahan didn’t let her experience scare her away from ultras or running in general (she’s even chasing running world records). She says that, as long as you’re used to the exertion, hydrating and eating properly, and letting yourself recover well, you should be fine. “When I had it, it was a new impact on my body,” she says. “In my subsequent 24 hour races I haven’t had it.”

So don’t worry too much about rhabdo. Yes, you can get it by running, but if you go about your training properly and work up to each new distance, it’s unlikely you’ll ever have to deal with it.