Lactate blood samples-are they reliable?

Hi just a question I need answered if possible, does a change in lactate concentrations at the earlobe reflect changes occurring within the muscles?

Thanks in advance

Yes. I think it is coz earlobe is blood supplied. Lactate conc in it reflects that of the blood which is also related to muscles. I think when an area is not supplied by blood it can be totally separated from that of supplied parts. Each has different characters.

Fakhry you haven't really answered the question.

And git z red your question is a bit confusing because your heading is asking about reliability, while the your actual question seems to be about a particular type of validity - namely sensitivity to change or responsiveness. Actually it is more complex than that because you also want to know if a change in lactate levels from your blood sample correlates with a change in lactate levels or some other aspect of muscle status in skeletal muscle. To determine that you will need to look at the concurrent validity of your particular blood lactate sampling method where it is compared to a gold standard for determining muscle lactate levels.

I think you have to look at the brand and method of collecting lactate blood samples as different machines may have different measurement properties. So base it on what the unit is you intend to use.

So:

search the literature for:

1. concurrent validity (or convergent validity failing that) for your method and brand and where the gold standard that samples muscle lactate concentrations is a valid, reliable and responsive measure of muscle lactate concentrations or some other significant measure of muscle status that you are trying to measure.

2. sensitivity to change and/or responsiveness of your method and brand

If you want to know the reliability (stability of the score on reproduction when no change is expected) that is a different but equally important issue.

Just in terms of having a clear understanding of what you are looking at I think you really need to familiarise yourself with what the various measurement properties are, how to critique this type of literature and what type of stats should be used. You shouldn't just be able to quote the data from studies but be able to determine if the study is of sufficient quality in order rely on the study