Effect of exercise on serum creatinine?
I recently got some blood test results which showed slightly high levels of serum creatinine (1.4 mg/dL, and the lab's reference range was 0.5-1.3).
Before getting these results, I hadn't even heard of creatinine. Now that I've had a chance to do a little bit of research, I know that creatinine is a byproduct of creatine that results from muscle metabolism. It is used to estimate kidney function; when the levels rise, it is assumed that the kidneys are not working as well.
Immediately I formed a hypothesis that eating lots of meat (which contains creatine) and strength training regularly would result in more serum creatinine. If enough creatinine were in the blood, even normally functioning kidneys might not filter out all the excess, which could lead to higher serum creatinine levels as seen in the test.
I've had limited success in debunking (or bolstering) this hypothesis. After a few hours of web research, I've read some articles/studies stating that exercise and diet have no significant impact on serum creatinine levels. Other articles say that there "may be" some minor increase in serum creatinine resulting from exercise. A couple articles alluded to possibly substantial increases resulting from exercise.
1) Does the hypothesis sound reasonable? If not, why not?
2) Do you know of any good studies debunking or bolstering the hypothesis?
3) Have you seen high serum creatinine levels in your blood test results?
4) Is it probable that increased muscle metabolism would persist for 48 hours or more after a vigorous strength training session?
Last edited by The Big L; 10-30-2010 at 03:05 PM.