My patient just attended her first spin class with her colleagues. Prior to this, she's been running and wakeboarding for exercise.
The doors to the studio were shut, while the air conditioning was turned off. Other than that, she didn't find pedaling fast on the stationary bike to rhythms of popular music while an instructor shouted motivation too difficult. Neither did she feel she pushed herself too hard. Her legs at the end of the hour long class weren't too sore or wobbly afterwards.
Over the next two days, her legs started throbbing and she came into the clinic to see me. I noticed bruises on her thighs and asked if she knocked them against the stationary bike. She said she didn't recall that happening.
The next day she noticed blood in her urine and checked herself into a hospital where she was warded and after blood and urine tests and was told her she had rhabdomyolysis.
Rhabdomyolysis is rare but can be a life threatening condition often caused by extreme exercise. It occurs when muscles that have been overworked dies and leak their contents into the bloodstream. This strains the kidneys and can cause severe pain.
My patient ended up staying in hospital for a few days before being discharged and has since recovered.
Subsequently I saw an article that documented three unusual cases of rhabdomyolysis, each occurring after a first spin class all treated by the same doctors (Brogan et al, 2017).
The article also described 46 other cases of people developing rhabdomyolysis after a spin class (42 of them in people taking their first spin class). The authors wrote that the condition was rare and not a reason to avoid high intensity exercise.
Another published study found 29 cases admitted to the emergency department between 2010-2014 for exercise induced rhabdomyolysis. Weight lifting, running, cross fit were some of the causes, but the most common cause was spinning classes!
The patients were not unfit, they were in fact being pushed too hard. Since they were not used to the new exercise, they ended up getting really bad muscle trauma.
Remember this next time you try a new exercise. Rhabdomyolysis occurs when you do not give your muscles time to adjust to a new aggressive exercise. When you stress your muscles too much, they tend to break down, releasing contents like myoglobin into your bloodstream which causes brown or tea colored urine, a classic symptom of rhabdomyolysis.
While any intense activity can cause rhabdomyolysis, it almost always strikes the person doing something new. So when you try a new exercise, start moderately first.
Know your limits, don't be pressured by the instructor. You can stop the exercise if you're struggling. Exercise can be dangerous when your body is not prepared for really intense levels.
References
Brogan M, Ledesma R et al (2017). Freebie Rhabdomyolysis: A Public Health Concern, Spin Class-Induced Rhabdomyolysis. AJM. 130(4): 484-487. DOI: 10.106/j.amjmed.2016.11.004.
Cutler TS, DeFilippis EM et al (2016). Increasing Incidence And Unique Clinical Characteristics Of Spinning-induced Rhabdomyolysis. Clin J Sp Med. 26(5): 429-431. DOI: 10.1097/JSM.0000000000000281.
Here's a picture of a spin class.
Picture from Soulcycle.com |