My CK was high after a race. Is something wrong?
A rise after long, downhill or eccentric work is expected and settles with rest, and people differ widely. A high CK after full rest with no other cause needs a medical work-up.
Brancaccio, Maffulli and Limongelli review the use of serum creatine kinase in sports medicine.
Areas of agreement, in their account: total CK depends on age, sex, ethnicity, muscle mass, physical activity and climate; in apparently healthy people a high CK may go with training status because it reflects sarcomere damage, and strenuous exercise that damages muscle raises it; the highest post-exercise values come after prolonged exercise such as ultra-distance running and after weight-bearing and downhill running, which involve eccentric contractions; total CK is markedly raised for 24 h after the bout and falls gradually towards baseline with rest; persistently raised CK is occasionally found in healthy people and is markedly raised in the pre-clinical stages of muscle disease.
Areas of controversy: whether a high resting CK in a healthy person is an early sign of myopathy or, in most, harmless; and whether hard training is safe for people with myopathy.
Growing points: an athlete with a high CK after complete rest and no other predisposing factor should have a full diagnostic work-up, watching for muscle weakness; an athlete with suspected myopathy can probably keep exercising at a lower intensity.
For research: CK varies greatly between individuals, with low responders whose CK stays low and high responders whose CK rises more, and the roles of training level, muscle size and fibre type in CK release remain to be worked out.
Our reading: this is the general physiology behind the base's "a load signature, not a fault" — CK rises after long, hard or eccentric work, how much depends on the person, and a high value says something about the session and the individual, not about readiness; the clinical line (a high resting value after full rest needs a doctor) is the review's own and is worth keeping.
Protocol
Key Results
The review's statements under its four headings (abstract; no numbers are given):
| Heading | Statement |
|---|---|
| Agreement — what sets CK | age, sex, ethnicity, muscle mass, physical activity, climatic conditions |
| Agreement — training | a high CK in apparently healthy people may relate to training status, since it depends on sarcomere damage; strenuous, muscle-damaging exercise raises total serum CK |
| Agreement — which exercise | highest after prolonged exercise (ultra-distance running) and after weight-bearing and downhill running with eccentric contractions |
| Agreement — kinetics | markedly raised for 24 h after the bout; with rest it gradually returns to baseline |
| Agreement — persistent rise | occasionally in healthy people; markedly raised in pre-clinical muscle disease |
| Controversy | whether resting hyperCKemia signals early, asymptomatic myopathy (some authors) or, in most people, no disease (others); whether intense prolonged exercise harms people with myopathy |
| Growing point | high CK in an athlete after absolute rest, with no other predisposing factor, should prompt a full diagnostic work-up, with attention to muscle weakness; suspected myopathy: continue at lower intensity with ample recovery |
| Research | great variability between individuals; low responders with chronically low CK and high responders; relation of training level, muscle size and fibre type to CK release still to be studied |
Mechanisms
Practical Application
Limitations
How this entry was checked and changed
a narrative review without systematic method and with no numbers in the abstract, from a sports-medicine department in Naples (as printed) rather than a muscle-damage laboratory, so held at C+ like REF-1350; being widely cited is not an evidence grade. Read from the abstract only: the publisher's page sits behind a bot check and OpenAlex lists no open repository copy