> The difference is that exercise is thought to help with those conditions and exacerbates ME/CFS It's proven to be the case. A repeat cardiopulmonary exercise

> The difference is that exercise is thought to help with those conditions and exacerbates ME/CFS It's proven to be the case. A repeat cardiopulmonary exercise (2-day CPET) is currently the only widely replicated biomarker for ME/CFS. Only ME/CFS shows a reduction in performance and a lowering of ventilatory threshold on the second day. Anyone else (sedentary, cancer, heart or lung disease, MS, depression) will show an improvement. [1] A study this year showed a striking effect looking at the metabolites in urine after exercising female ME patients vs sedentary healthy controls. The ME patients just did not excrete metabolites as the healthy controls did. [2] "This indicates that ME/CFS patients have a general metabolic dysregulation that is part of their exercise intolerance and PEM in which altered metabolic excretion is a contributing factor." There's also a very simple clinical discriminator between ME/CFS and depression. If you ask a depressed person what they would do if they were suddenly cured, their answer will be "Not sure, I don't know, I can't think of anything, nothing really." If you ask someone with ME/CFS the same question, the response would be "Go to the shops, drive my car, walk on the beach, see my friends... etc". [1] https://www.mdpi.com/2227-9032/8/3/192 https://www.mdpi.com/2227-9032/8/3/192 [2] https://www.mdpi.com/1422-0067/24/4/3685 https://www.mdpi.com/1422-0067/24/4/3685