Creatine kinase supports an energy reserve
Biomarker library
Muscle & Joint Health
Creatine kinase
Creatine kinase (CK) is an enzyme your muscles use to recycle energy quickly while they contract.
Measured in your health assessment, with a doctor to explain your result. Book yours
Why it matters
When muscle fibres are strained or damaged, CK leaks into the blood. Hard exercise can raise it many times over for several days, so the timing of your last workout matters when reading it.
What a result can mean
Lower than the range
A low CK reflects lower muscle mass and is rarely significant.
Higher than the range
The commonest cause is recent strenuous exercise, especially a new or unaccustomed workout. Other causes include muscle injury, falls, some medicines (notably statins), an underactive thyroid and, rarely, inflammatory or inherited muscle conditions. People of African ancestry naturally have higher levels.
What can help
Avoid strenuous exercise for two or three days before a test. If CK is high and you have muscle pain while taking a statin, tell your doctor, who may adjust the treatment. Persistent unexplained rises are investigated.
Read it with
NoteGeneral educational illustration. Colours, sizes and movement are simplified. This is not a scan or a simulation of your body. General information, not personal medical advice: a doctor reads your own results with your history.
Know your creatine kinase.
Measured in your health assessment and explained by the doctor who reviews your results.