Effects of exercise and lovastatin on serum creatine kinase activity

Vigorous physical activity and lovastatin (Mevacor) a 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase inhibitor, have both been independently associated with elevated creatine kinase (CK) levels. To determine the effect of lovastatin plus exercise on serum CK activity, we measured CK levels before and after maximal treadmill exercise in 14 men (51.6 +/- 17.3 years, mean +/- SD) and 6 women (48.5 +/- 7.4 years) before and after 4 weeks of lovastatin treatment (20 mg/d). Blood samples were obtained before, immediately after, and 24 hours after exercise. Individual subjects were exercised for the same duration on each test. Preexercise CK levels and the average CK response to treadmill exercise did not differ before and after lovastatin treatment. In two men taking lovastatin, however, CK levels increased by 183% and 242% 24 hours after exercise during lovastatin administration. We conclude that low-dose lovastatin treatment plus exercise does not affect average CK activity but that this combination may markedly increase CK levels in certain individuals.