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GH and lactic acid? for Bill Roberts

I have a question concerning GH and lactic acid. Do you have any references that lactic acid increases GH. I had a meeting with my graduate professor and we were talking about GH and I told him how I had read off this sight that lactic acid supposedly increases growth hormone. My professor said that pH increases GH, but he didn’t think that lactic acid increased it…other than lowering the pH in the body. I did a search on PubMed, but found nothing. Can you help me to find a few references…my interest is peaked and we might due some research with it if I can show him some good data to persuade him…thanks in advance.

I don’t have a reference on that, never looked into it myself.

Blood lactate levels certainly do rise when performing work at a high rate. Your professor is however correct that blood pH does not change very much, due to buffering.

I’d have very little advantage over you,
if any, in terms of being able to find
references specifically on this topic.
It does sound interesting, hope you find
something!

I think this reference would refute your assertion.

Sutton JR; Jones NL; Toews CJ. Growth hormone secretion in acid-base alterations at rest and during exercise. CLINICAL SCIENCE AND MOLECULAR MEDICINE. vol. 50, no. 4 (1976 Apr): 241-7.

Although, 3-5 mM lactate is not that high. It is conceivable that a higher blood lactate might elicit a different response. On the other hand, we know that endurance athletes have an enhanced GH response with training at a given exercise load, while at the same time they would have a reduced lactate response. So that would argue against lactate having a positive causative correlation with GH. It is likely that someone made that assertion because it is generally accepted that GH is positively correlated with intensity, as is lactate, and so they assumed that lactate resulted in elevated GH. I don't think this is so, though. Sorry.

But,... you don't know until somebody does the experiment that refutes the hypothesis. I doubt if your advisor will buy that one though.

all - on a related note concerning pH levels…when on a ketogenic diet the blood becomes more acidic. does this have a positive or negative effect on GH? kevo