Metabolic health
Creatine kinase (CK)
CPK, creatine phosphokinase
Included in Baseline and Complete.
Compare membershipsWhat your muscles release after hard work.
Creatine kinase is an enzyme that helps your muscles make energy. A small amount reaches your blood from everyday wear and tear, and levels rise when muscle is strained or damaged.
Your last workout can show up in this result.
Hard or unfamiliar exercise can raise CK for a few days, and so can muscle injuries and some muscle conditions. Age, sex, ethnicity, and how active you are also influence what's typical for you.
Some medicines, including statins, can affect muscles and raise CK. Smaller amounts of CK come from the heart and brain, but this test is mainly read as a marker of skeletal muscle, the muscles you use to move.
A raised CK after a tough training week is often expected.
Questions
Should I avoid hard exercise before my blood draw?
It helps. Intense exercise in the days before your draw can raise CK and make the result harder to read, and alcohol can also affect it. If you trained hard, mention it so your result can be interpreted fairly.
What if my CK stays high?
A CK that stays raised without a clear reason, such as recent training or an injury, is worth discussing with a clinician. They may repeat the test after rest and look at your medicines, any muscle pain or weakness, and your other results.
Does CK matter if I take a statin?
Statins can cause muscle symptoms in some people, and CK is one of the results used to look into them. If you take a statin and notice new muscle pain or weakness, talk to your prescriber before making any change.