I've never had it affect my cholesterol level, but a hard workout has affected my CREATININE level.

I have a test coming up in 2 days.  Hadn't really given this any thought - since I run every morning, seems like that is my "normal".  Interested in hearing replies from med professionals here.

It most likely won't have an affect considering cholesterol is gained/lost gradually not overnight. That being said you may have other skewed results that your doctor may want to continue testing you for. I recently experienced from my own blood test where my bilirubin, liver enzyme, was elevated. I did a little research and discovered that bilirubin is responsible for recycling red blood cells. Considering the fact that I was doing hard interval repeats at that point in my training I considered that to be acceptable and has never caused me any health issues. Also I tested high for thyroid enzymes as well, but again seeing as my metabolism would be elevated from competing I again saw no reason for concern. All things considered, train how you like and when the results come in don't entirely rely on your doc's interpretation.

On my last test I also had the Dr tell me that I had a high bilirubin level and I most likely had something called Gilberts syndrome after checking and finding the level was cause by dead red blood cells, I think my daily running was the cause for this level but all my other levels were awesome.

Wing:

I did a quick lit search and found this:  http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1859549/pdf/brjsmed00268-0037.pdf

In this study of males (of varied age and fitness levels), their cholesterol levels were elevated from baseline during and immediately after exercise.

I would interpret those results with caution, however.  For example, if you don't fit into the study population (e.g.,  if you are female), the study results may not be applicable to you.  In addition, although reasonably designed, the study was a relatively small one.

Here is another study that addresses this question.

J Sports Med Phys Fitness. 1988 Mar;28(1):7-10.

The effects of acute physical exercise on blood serum cholesterol, triglycerides, human growth hormone (H.G.H.) and free thyroxine (T4) in men over fifty years of age.

Métivier G, Gauthier R

However, I can't access the full paper on the road, so I can't comment on the study or results.  (Obviously, this study would not necessarily apply to you if you are a female or a male under 50 years of age).

Other than that, I couldn't find a lot that addresses your specific question.

You may wish to skip that morning's run, so that you remove the possible influence of short term exercise on your results.  (If you don't, and you get an abnormal results, you'll probably end up spending more money to make sure it was real).

Good luck--hope this helps a little..

PS:  The other comments about glucose level are probably correct (although not as much as you might think--assuming you aren't a diabetic, have liver disease, etc.).    Other possible labs that might be influenced would be your hemoglobin/hematocrit if you grossly overhydrate or underhydrate on a lengthy training run in unfavorable weather.  Also, if you have a vigorous run, your creatine kinase might be bumped a bit (but that test is not part of the usual health maintenance labs..