The Dark Side of Extreme Exercise: Rhabdomyolysis
It’s no surprise that professional sports players are expected to endure brutal workouts in order to prepare for real play time. You’ve likely also heard of the teen and college sports players’ strenuous workouts in extreme weather conditions (heat). These types of workouts can certainly prepare the players for the challenge of game time. The problem is that they can also result in serious health outcomes. These dangers also occur among regular exercisers who engage in prolonged extreme workouts. One type of life-threatening event that can occur is called rhabdomyolysis or** rhabdo**.
A recent news report in the Chicago Tribune covered the recent events that brought three Oregon college football players to the hospital. The athletes had just finished a very taxing off-season workout and began to experience aches and pains and noted that they were passing very dark colored urine. The dark color of the urine is one sign that there has been dramatic breakdown and destruction of skeletal muscles and the production of a protein by-product called myoglobin. If enough myoglobin is produced and enters the bloodstream, it can plug up the kidney’s filtering tubes and cause direct injury to the kidney.
Rhabdomyolsis can also result in an electrolyte shift, because the muscle injury results in the release of high levels of potassium into the bloodstream (hyperkalemia) as well as high levels of phosphorous (hyperphosphatemia). Very high levels of these electrolytes can affect the heart, resulting in damage to the heart muscle.
Another serious outcome of rhabdo is called compartment syndrome. In this situation the injury to the muscles leads to extreme swelling in an area of the body where there is limited space. This can ultimately compromise circulation which can endanger the health of local tissue. This can occur in the lower legs (calves), arms (biceps) and even the muscles of the abdominal wall. It can require emergency surgery in order to alleviate the pressure and save the tissue.
In the case of rhabdo among the three college athletes, the clear cause was an extreme and unrelenting workout. Other causes of rhabdo include:
- A sudden muscle trauma (or crush injury)
- Severe burns
- Prolonged cocaine use accompanied by hyperthermia
- A familial version of the disease (familial paroxysmal rhabdomyolysis)
- A viral or bacterial infection
- Muscle inflammatory diseases like myositis
- Certain medications including statins, colchicine, and some Parkinson’s drugs
- Sudden depletion of electrolytes
Rhabdo has also been reported among exercisers who participate in one of the more recent trends in fitness, CrossFit. First reported in 2005, there is a clear risk of rhabdo in certain individuals who engage in an intense and prolonged CrossFit exercise session. The CrossFit workout is certainly vigorous, often prolonged, and because of its motivational format, can inspire exercisers to push too hard for too long a duration of time. Newcomers to this challenging workout discipline can be especially vulnerable to the condition, though it’s obvious that it can happen to anyone who persists in an extended and brutal workout. You might also be at higher risk if you have one of the above mentioned risk factors.
Prevention is obviously the best way to limit the serious outcomes of this condition. Hydrating well, before, during and after the workout is one way to lower your risk. Pacing yourself during a vigorous workout and being mindful of your body’s response to a vigorous workout is also important. If you start to cramp up or feel serious muscle pains, then it’s time to stop and take a break. Not allowing a trainer or group instructor (or fellow exercisers) to push you beyond reasonable efforts is also important. If you are a beginner, ease into the workout intensity by taking several weeks to acclimate. If you notice dark “Coca Cola” colored urine after an intense workout, get checked out by a healthcare provider immediately.
If you experience true rhabdomyolysis, you may need to be hospitalized. If the cause is other than an intense workout, the doctor will try to eliminate that situation or agent. You will likely receive intravenous fluids and there will be an effort to normalize your electrolytes. Efforts will also be made to prevent kidney damage. Doctors will monitor certain muscle enzyme levels (CPK, SGOT, SGPT, LDH). Prompt diagnosis and treatment is critical, but most cases of rhabdo are reversible. If there is kidney damage, dialysis may be required.
Studies like The Effects of 10 Days of Extreme Endurance on Performance, Buffering Capacity During Exercise and Post Exercise Muscle Damage, Oxidative Stress and Inflammation, conducted at the University of Louisiana at Lafayette, suggest that certain sports nutrition products may also help to prevent rhabdo by helping to limit muscle trauma. More studies on the efficacy and safety profile of nutrition products like this are needed. Since oxidative stress is one of the components of rhabdo, it’s also interesting to note that a 2015 study suggested that eating a diet rich in antioxidants and phytochemicals (both found in fruits and vegetables) can help to mitigate exercise-induced oxidative stress. That is one dietary habit that is delicious and effective.
What is clear is that the National Collegiate Athletic Association (NCAA), high school level sports departments, and professional sports teams need to balance the need for intense training protocols with the many dangers of over-exercising, including rhabdomyolysis.
See More Helpful Articles:
Amy Hendel, also known as The HealthGal, is a Physician Assistant, nutritionist and fitness expert. As a health media personality, she's been reporting and blogging on lifestyle issues and health news for over 20 years. Author of The 4 Habits of Healthy Families, her website offers daily health reports, links to her blogs, and a library of lifestyle video segments.