A 42-year-old woman received a 6-month course of simvastatin (20 mg/d) for hypercholesterolemia. Despite an infection with fever, fatigue, myalgias, and lumbar pain, she continued to perform her regular sports activities. Neurologic examination revealed bilateral ptosis and slight upper limb weakness. Serum creatine kinase was 41,000 U/L. Needle electromyography was nonspecifically abnormal. Discontinuation of simvastatin and reduction of the sports activities was followed by a prompt continual lowering of the elevated muscle enzymes to normal values over a 2-week period. The patient's infection, regular sports activity despite the infection, and a suspected mitochondrial defect were regarded as triggers of rhabdomyolysis.