In some disease conditions elevated cpk levels are measured. Most common conditions are associated with inflammation of the skeletal muscles or myocardial necrosis. But in addition to these even after moderate exercise elevated cpk levels can be observed. In the medical point of view elevated cpk levels are of invaluable in diagnosing certain disease conditions. For an example in Duchenne muscular dystrophy blood cpk levels are highly elevated even before the appearance of clinical symptoms. Even though elevated cpk levels can be used in diagnostic process this test is not very specific. For an example skeletal muscle and heart muscle both contain cpk enzyme. So damage to either organ can cause an elevated cpk levels. Another thing is the time duration after the injury. So one has to be careful about the time duration. Otherwise the test results may not be accurate.
See also,
Use of CPK test in Heart attack
CPK test in duchenne muscular dystrophy
CPK test in myocardial infarction
CPK test in polymyositis
