I was thinking about the NIH's request for input on what and how to study ME/CFS and how most (all?) of us consider the 2-day exercise stress test to be crucial for any research. However, because of its nature, it would be possibly quite harmful for many if not most of us to actually do the test. (what a dilemma! ) It occurred to me last night that the 2nd day part of the test measures what has happened in the body in response to the first day's stress test. So I was wondering if there might be some sort of blood test (or urine? whatever) done on day 2 that could measure the effects of the first day's stress test, and avoid the 2nd day stress test altogether. For me, the 2nd day is what would potentially be most harmful, when my ATP is so low and I can't really function, I can't imagine doing a stress test then. When I crash (PEM), it feels like my lactic acid levels rise - I can tell when a crash is abating when the achiness dissipates. So I was thinking perhaps measuring lactic acid levels rising and falling in response to a one-day test might be an indicator of PEM, and thus avoid the 2nd day stress test. Or measuring something else, metabolites, I don't know what, I'm not a scientist, but I'm just thinking there have got to be measurable abnormalities present while we are crashed. I never see the doctor when I'm crashed for obvious reasons, so blood's never taken then. So many are urging the NIH to include the 2-day exercise stress test, but I think we need a way to achieve the same thing without harming ourselves. Any ideas?