Yes, the Times article does state that the controls were sedentary, which is of course a very important issue in this particular study. I think this may well be a very significant milestone, politically at least. Is this the first ever government/MRC-funded study to demonstrate biological abnormalities in ME/CFS? Excess lactic acid in ME/CFS patients is not really news, I think, but demonstrating it in vitro is new to me.
It has really got me thinking about where it fits as a link in the chain of symptoms, because it seems to me that it may fit in quite a clear way. Excess lactic acid production will obviously cause much greater pain and fatigue, but I'm interested in how this might fit in with sleep and PEM. PEM symptoms typically come 24-48 hours after exertion - or to put it another way, after 1-2 night's sleep with masses of excess lactic acid. Anybody have any clues on the biology of how excess lactic acid might be expected to produce the other known PEM symptoms, and the inflammatory markers of PEM found by the likes of the Lights' studies? And then, in the other direction, any thoughts on what kind of cell malfunction (eg mitochondria issues) might cause excess lactic acid production?