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Rhabdomyolysis is a pathologic condition in which intracellular muscle constituents leak into the blood circulation. It is usually caused by muscle trauma. “Spinning” is an indoor form of cycling where participants use a special stationary exercise bicycle with a weighted flywheel and undergo high-intensity cycling classes focusing on endurance. There have been several case reports in the literature of exertional rhabdomyolysis following spin class.
Our nephrology practices have diagnosed a number of cases of symptomatic patients presenting to our emergency departments following their first spin classes, with histories and creatinine phosphokinase levels diagnostic of exertional rhabdomyolysis.
We present 3 unusual cases of exertional rhabdomyolysis, each occurring after a first spin class. In the first case, rhabdomyolysis developed following 15 minutes of spin class. In the second case, it occurred in a young individual who exercises regularly. In the third case, the patient developed biopsy-proved acute kidney injury secondary to exertional rhabdomyolysis and required hemodialysis.
The high-intensity exercise associated with “spin class” comes with significant risks to newcomers.
This syndrome occurs when muscle injury leads to leakage of muscle cell contents, including electrolytes, myoglobin, and other sarcoplasmic proteins (eg, creatinine phosphokinase [CPK], aldolase, lactate dehydrogenase, alanine aminotransferase, and aspartate aminotransferase) into the circulation and extracellular fluid.
Spinning is a cardiovascular workout for all levels of fitness using stationary cycles. Participants adopt different positions and vary the resistance on the cycle, thus simulating climbing hills, cycling on flat roads, and sprint cycle.
This involves repetitive use of the large muscle groups, mainly the gluteus maximus and quadriceps muscles.
Risk factors for the development of rhabdomyolysis are related to the intensity of the exercise, the conditioning of the participant, hydration, and body temperature, in addition to other potential contributing factors. Physiology studies have demonstrated that significant numbers of calories are burned,
Two objective measures used to evaluate the exercise “intensity” experienced by “spinners” include Ventilatory Threshold and Percentage Heart Rate Reserve. Ventilatory Threshold is a measure of cardiovascular fitness, which refers to the point at which lactate begins to accumulate in the blood. Percentage Heart Rate Reserve represents the percent difference between the predicted maximal heart rate and exercise heart rate. Studies have demonstrated that healthy, physically active females spent 52% of a 45-minute class at intensities greater than Ventilatory Threshold.
The Percentage Heart Rate rating in healthy individuals ages 18-38 years who were already going to the gym and had at least 4 spin classes prior to testing were classified as “hard” intensity according to the American College of Sports Medicine. Based on these measures, “spinning” is considered an intense exercise mode.
The risk of rhabdomyolysis has been related to the adequacy of physical conditioning of subjects and to the duration of the intensity of the exercise.
Exertional rhabdomyolysis after a spin class has been reported in 46 cases; 42 of these cases occurred following a first spin class. Patients who developed exertional rhabdomyolysis were described as “deconditioned” in some of these trials.
and a risk for rhabdomyolysis in the untrained individual. We present 3 unusual cases of rhabdomyolysis following a first spin class.
A 33-year-old woman presented with bilateral thigh pain and weakness 4 days after 15 minutes of spinning. She dismounted the bike for symptoms of lightheadedness and vomiting. On presentation, she had thigh weakness, tenderness, and swelling. Labs showed creatinine 0.5 mg/dL, aspartate aminotransferase (AST) 1092 U/L, and alanine aminotransferase (ALT) 282 U/L. Urinalysis showed 1+ proteinuria, 3+ blood, and 0-3 red cells/hpf. She was aggressively hydrated. Her peak CPK was 60,000 U/L.
A 20-year-old man with a history of Gilbert syndrome presented with bilateral thigh pain 3 days after spinning. He was unable to lift his lower extremities against gravity. There was thigh tenderness and swelling. Initial blood work showed creatinine 0.8 mg/dL, AST 1140 U/L, ALT 270 U/L, and CPK 14,493 U/L.
Urinalysis showed 2+ proteinuria, 3+ blood, and 3-5 red cells/hpf. His peak CPK was 132,832 U/L.
A 33-year-old woman presented with thigh pain, decreased urine output, nausea, and vomiting 2 days after spinning. She had thigh tenderness and swelling. Serum creatinine peaked at 6.8 mg/dL, ALT 2583 U/L, AST 742 U/L, lactate dehydrogenase 10,167 U/L, and CPK peaked at >80,000 U/L. Despite aggressive hydration with normal saline, she required hemodialysis for oliguria. Due to the severity of her renal failure and history of nonsteroidal anti-inflammatory drug use, a kidney biopsy was performed, which confirmed rhabdomyolysis (see Figure 1, Figure 2, Figure 3). Her creatinine improved to 0.7 mg/dL 5 1/2 weeks later, with normalization of her CPK.
Exertional rhabdomyolysis causes overproduction of heat, which leads to an increase in intracellular calcium, activation of proteases, and production of reactive oxygen species. Necrosis of skeletal muscle cells releases intracellular contents, causing pain, swelling, and potential end-organ damage in the athlete.
There is a wide interindividual variability in the phenotypic expression of muscle damage. Apart from environmental factors, several gene-specific single nucleotide polymorphisms were found to be associated with the magnitude of exercise-induced muscle damage.
Rhabdomyolysis can present with symptoms from mild muscle soreness and swelling to organ dysfunction. Symptoms include fatigue, nausea, and vomiting. An accurate history of the patient's existing medical issues, medications, activity, hydration status, and ambient temperature at the time of activity is essential.
Treatment of exertional rhabdomyolysis begins with aggressive intravenous fluid hydration.
Exertional rhabdomyolysis is caused by intense exercise, more commonly in an untrained athlete.
We describe the most severe case of rhabdomyolysis requiring dialysis and a case after a brief duration of spinning. The only way to prevent rhabdomyolysis from spinning is to have safety guidelines set up. Beginners need to know how to gradually increase the time and cadence on the indoor cycle. They need to be made aware of the importance of staying hydrated and the need to avoid nonsteroidal anti-inflammatory drugs. Participants need to be informed of the risks of rhabdomyolysis. Guidelines should include information about the signs and symptoms of rhabdomyolysis and the urgency of seeking hospital treatment when such manifestations occur.
Bench-to-bedside review: rhabdomyolysis – an overview for clinicians.