Is Rhabdomyolysis Affecting You?
I first heard about rhabdomyolysis a few years ago on a forum. I briefly read up on it and concluded that it happened in extreme cases with underdeveloped athletes being pushed too hard by unqualified coaches.
This week I was shocked to hear about a case here in Canada. I had a chance to speak with my friend Jenny Chu, a 3rd-year medical student who worked on the case.
A fit, mid-30s female, and experienced CrossFitter, well-conditioned to do regular HIIT fell ill to rhabdomyolysis. She was not doing an official WOD, but her own programming doing an AMRAP pull-ups.
The athlete was used to doing eccentric arm movements but did a new workout focusing heavily on concentric exercises. She noticed increased arm pain and weakness the day after her workout and went to hospital complaining of arm weakness and severe pain in the affected limbs.
What is rhabdomyolysis?
Rhabdomyolysis (From Greek origins roughly: Rhabdo – rod, myo – muscle, lysis – breakdown = breakdown of striped muscle) is the cluster of signs and symptoms caused by the release of muscle cell components into the bloodstream after muscle cell death. This is toxic to the kidneys and can result in coloured, red/brown urine.
Why do we care?
Potential complications if not treated and monitored appropriately:
1) One of the components released may cause the kidneys to stop working, causing “acute renal failure.”
2) The levels of certain salts in the bloodstream can change. These salts are necessary for many bodily functions, including maintaining a regular heart beat.
3) Some people may develop an increase in pressure within the surrounding limb that may reduce the blood flow and damage the nerves in the area.
4) You can die.
What are the Symptoms?
1) Muscle pains much more severe than they should be for the type of workout done.
2) Weakness – Some people describe barely being able to move the affected limb.
3) Dark urine (red to brown) – Seen in 50-60% of cases – Not having dark urine does not mean you do not have rhabdomyolysis.
4) Some people may additionally experience general malaise, fever, increased heart rate (over 100 beats per minute), nausea and vomiting, abdominal pain. Depending on the underlying cause of the rhabdo, changes in mental status may also be noticed.
Not all people will experience the same degree of muscle pains, urine colour changes. If you have the above symptoms, you should seek medical assessment for blood and urine tests.
Things Observed in Hospital:
1) Elevated Creatine Kinase levels (an enzyme released from the muscles).
2) Elevated myoglobin.
What causes it?
Here’s where it gets confusing. I have personally done, as I’m sure many readers have, workouts of such high intensity and difficulty, they have resulted in extreme reactions.
Squats until vomiting. Rugby games where I could barely get off the field. I even climbed a mountain and couldn’t walk for a solid week. So why would a challenging workout of pull ups, cause a near death reaction?
The exact cause of rhabdomyolysis is unknown. Many people can do the same exercise or activities yet only rarely will anyone develop rhabdomyolysis.
There are many causes that may contribute to the development of rhabdomyolysis, and some people may have more than one contributing cause, including:
1) Muscle injury, either traumatic or after surgery, is also seen in individuals struggling against restraints.
2) Very intense exercise, when energy supply to the muscle is not enough to meet demands in trained and untrained individuals.
3) Underlying deficiencies of certain salts within the bloodstream, notably a lack of potassium.
4) Diabetes and thyroid disease.
5) Severe Asthma.
7) Extended bedrest without movement.
8) Some infections.
9) Toxins – carbon monoxide, snake or insect bites.
Some drugs (Alcohol, recreational drugs, cholesterol-lowering drugs.
10) Some genetic causes.
Why some people and not others?
Due to the number of causes that can contribute to the development of rhabdomyolysis, it is hard to predict who will become affected.
Some people are at increased risk due to their genetics but often will not find out until they have a case of rhabdomyolysis.
There is no magic number of reps or maximum weight that creates the threshold for developing rhabdomyolysis. There is no evidence to prove that rhabdomyolysis can be prevented by gradually increasing the strain on each muscle group, but anecdotally it seems that people most often run into troubles with high-intensity use of muscle groups not previously conditioned.
The key to dealing with rhabdomyolysis might not be in the prevention of it, but rather in the recognition and subsequent actions of the syndrome to prevent the long term poor outcomes.
By Kaevon Khoozani & Jenny Chu
1. Clinical manifestations and diagnosis of rhabdomyolysis
Author Section Editors
Marc L Miller, MD
2. Causes of rhabdomyolysis
Author Section Editors
Marc L Miller, MD