Your body produces the enzyme creatine kinase (CK) or creatine phosphokinase to keep your muscles functioning properly.

Background: The serum concentration of creatine kinase (CK) is used widely as an index of skeletal muscle fibre damage in sport and exercise. Since athletes have higher CK values than non-athletes, ...

Cardiac enzymes ― also known as cardiac biomarkers ― include myoglobin, troponin and creatine kinase. Historically, lactate dehydrogenase, or LDH, was also used but is non-specific.