what is normal cpk
Creatine Kinase. Creatine kinase formerly known as creatine phosphokinase is primarily found in muscle cells including the heart, striated muscles and the brain. The normal range of creatine kinase for men is 38 - 174 units/L and for women 96 - 140 units/L. Men typically have more muscle mass than women which accounts for the higher range values. African Americans have been found to have higher normal range for creatine kinase as well.