In brief Numerous physiologic derangements can result when body-builders attempt to augment their muscle definition by using diuretics, potassium supplements, and dietary restrictions. A case report describes a 27- year-old male professional bodybuilder who employed these strategies and presented with profound muscle weakness and muscle cramps. He was found to have life-threatening hyperkalemia, ECG changes, mild rhabdomyolysis, and prerenal azotemia. Vigorous volume expansion and potassium-lowering maneuvers reversed the skeletal muscle and cardiac complications. The patient's symptoms resembled those of another professional bodybuilder who died after employing similar drug and diet strategies.