Let’s talk about Rhabdo, folks. Rhabdo is CrossFit’s “Dirty Little Secret;” something you hear about happening to someone at another gym. Everyone seems to know a friend of a friend of a friend that “got Rhabdo from CrossFit.” Google “CrossFit and Rhabdo” together and you’ll see about 31,900  results and thousands of blogs about CrossFitters’ experiences with this condition . In fact, CrossFit has an unofficial Rhabdo Mascot, Uncle Rhabdo. Rhabdo jokes are frequent at the gym and on CrossFit shirts, but it won’t be funny if it happens to you.


According to the National Center for Biotechnolgy Information at the U.S. National Library of Medicine,  Rhabdomyolysis (“Rhabdo”) is the breakdown of muscle fibers that leads to the release of muscle fiber contents (myoglobin) into the bloodstream. Myoglobin is harmful to the kidney and can cause kidney damage. Rhabdo may be caused by any condition that damages skeletal muscle, especially injury.

There are several risk factors for contracting Rhabdo and they include the following: Alcoholism, Crush injuries, Drugs: especially cocaine, amphetamines, statins, heroin or PCP, Genetic muscle diseases, Heatstroke, Ischemia or necrosis of the muscles, Low phosphate levels, Seizures, Severe exertion (such as marathon running or calisthenics), Shaking chills, and Trauma. Symptoms of Rhabdo include Abnormal urine color (dar, red or cola colored), Decreased urine production, General weakness, Muscle stiffness or aching, Muscle tenderness, and Weakness of the affected muscles.

Your pee should not look like this:

Your Pee Should Not Look Like This!

Symptoms of Rhabdomyolysis are non-specific and may not be present, so clinical testing is the best way to diagnose the condition. The two most important factors are creatine kinase (aka CK, a muscle enzyme) and myoglobin (a muscle protein). Extremely elevated concentrations of CK in the blood confirms the diagnosis; however, it is the presence of myoglobin in the urine that generally alerts the athlete that something is really wrong. (When myoglobin appears in the urine, the unrine color changes to dark brown.)


In CrossFit we worry about Exertional Rhabdomyolisis, which is the degeneration of skeletal muscle caused by excessive, unaccustomed exercise. This rare, but serious complication of too much exercise can affect people of any race, age or fitness level. It has happened to military recruits, “weekend workout warriors,” marathon runners, and even experienced CrossFitters. This muscle damage that arises from overexertion of the muscles can happen to anyone, but usually occurs in the untrained or when high-heat/high-humidity conditions are present and an individual is severely dehydrated and fatigued.

CrossFitters will experience sore muscles. Often. That’s just part of CrossFitting. Sometimes CrossFitters will even experience some slight swelling and pain in muscles and joints. Again, that’s part of CrossFitting and hard training. These sore muscles and minor swelling/joint pain from overexertion do not indicate Rhabdo, but they could be accompanied by slightly elevated CK levels in the blood. This is normal and recovery is fairly rapid.

Rhabdo is much more than run-of-the-mill muscle soreness that lasts for a couple days. When the soreness and pain are accompanied by extreme swelling of the affected muscles, a physician should be consulted to make sure the condition hasn’t develped into Rhabdo. If the muscle soreness and swelling are accompanied by dark urine, get yourself to the ER. Stat! You do not want to go into renal failure. Recovering from a bout of documented acute exertional Rhabdomyolsis could take weeks or months, depending on the severity of the condtition.


The good news is that a) Rhabdo is very rare and b) Rhabdo is completely preventable. One way to help reduce the chance of Rhabdo is to maintain proper hydration before, during and after working out. Another way to avoid Rhabdo is to maintain a regular fitness routine. We want you to work hard, but be smart. If your CrossFit Trainer tells you to back off the weight or the intensity of the workout, listen! If you’re dehydrated, fatigued or just not feeling right that day, make sure you back off the intensity on your own. This is not the time to do two or three workouts in one day. If you’re taking a statin or any other drug – or if you have a serious medical condition – make sure your trainers knows this as well.

CrossFit training is hard, but it isn’t intended to put you in the hospital. Work hard, play harder and train smart!

Showing 4 comments
  • Someone at Another Gym

    It’s great that you’re educating your athletes about rhabdo, Incendia. I was lucky enough that my gym had done the same so I knew I needed medical attention when my urine turned brown.

    In addition to the ways to prevent rhabdo that you’ve identified I would add “beware of negatives.” Burpees put me in the hospital for 5 days with rhabdo after a break from CrossFit. Because we can lower ourselves to the ground using a fatiguing muscle group longer than we can push ourselves back up, negatives – like those in burpees – can increase the risk inducing rhabdo.

  • Michael Crosby

    Here is my untrained thought on negatives: As SOMEONE AT ANOTHER GYM says, we can use fatigued muscles in negatives longer than in positives. To me this does not mean all negatives are bad, but that, especially if your new, negatives should be incorporated in the beginning of a work out. If positives are focused on at the end your body will tell you it can’t do something by, well, um, not doing it. In the case of burpee’s, if your muscles are spent, and then you go into a burpee move, your brain will not let you do a face plant, so your arms will assist you in the lowering even well into major damage to the muscle.

    Mike Crosby

  • David Ballard

    This is great, as all the things we experience or see others toil through, it is our job to let those who choose to embark on a similar journey be educated by those who have blazed the path. If we as brother and sister athletes don’t look out for each other then those who intend harm will have the crevis of which to plant their distraction and ultimate discouragement. As stated, all things have a season, a blending of general fitness, hydration and rest. Then you”ll be consistently able to raise the bar of excellence. Cch D Powerhouse SJ ca.

  • Barb

    I think your post grossly understates some of the problems of rhabdo. Your muscle cells are essentially exploding, and the damage may be permanent. Rhabdo can lead to kidney damage and even death.

    Per a Huffington post article:

    “What does CrossFit’s founder, Greg Glassman think of this?
    “It can kill you,” he said. “I’ve always been completely honest about that.”

    I don’t think drinking more water and dropping a little bit of weight off your bars is sufficient enough prevention. Anyone reading this post or considering cross fit (or any work out routine) should do their own research and consult a doctor. It isn’t something to jump in to uneducated.

    http://www.huffingtonpost.com/eric-robertson/crossfit-rhabdomyolysis_b_3977598.html )