This submaximal exercise testing protocol revealed attenuated changes in oxygenated and deoxygenated hemoglobin, which may be attributable to poor exercise tolerance and rapid fatigue seen in ME/CFS compounded by decreased fitness. Because of the variable responses among participants, it does not provide a clear distinction between cases with ME/CFS and healthy controls and is therefore not a useful diagnostic marker. However, testing did reveal a disproportionate level of perceived exertion and lower force production in cases with ME/CFS, and in two cases, adverse responses to low levels of exercise. The repetitive handgrip protocol may be useful to screen individuals for adverse responses and other conditions, including mitochondrial disease. It may also be useful for stratifying ME/CFS sufferers to determine appropriate levels of exercise prescription.
There are a number of issues with this study. I'm just going to mention a few.
Obviously the first one is "This submaximal exercise testing protocol revealed attenuated changes in oxygenated and deoxygenated hemoglobin, which may be attributable to poor exercise tolerance and rapid fatigue seen in ME/CFS compounded by decreased fitness."
So you find abnormalities which you don't want to find and and then you just come up with some nonsense to say they're not important. Typical Pinocchio doctoring.
If you look at the average BMI of the healthy controls and patients then there is a massive difference.
In patients it's on average 25.1 and in healthy controls 20.8. Simply put, I'm 175 cm. If my BMI was 25.1, my weight would be 76.9 kg and if my BMI was 20.8 it would be 63.7 kg. And that's a difference of 13.2 kilo which is 17.2 percent and that's a massive difference. And you cannot use healthy controls who are very slim and compare those with patients that are not.
If you look at the following sentence, "All cases and no healthy controls fit both the Canadian case definition and the CDC Fukuda definition of ME/CFS" it actually means that healthy controls can actually have ME/CFS as defined by Fukuda or defined by CCC but not by both. Which means that the healthy controls might not be healthy controls at all and they might actually have ME/CFS.
The researchers selected 25 ME patients and 25 healthy controls but they only analysed 16 of both. In the patient group they explained why they couldn't use 6 of the 25, which means that 3 were unaccounted and in the healthy controls 5 were accounted and 4 unaccounted. And in a small group that's a large percentage which is unaccounted. That should not happen but that is something which happens a lot in denial doctoring as Frank Twisk has shown repeatedly when he analysed studies by Nijmegen etc
There is one other interesting thing I would like to mention. "The CCD study pre-screened 102 people and excluded 52:24 with another diagnosis (e.g., sleep apnea, hypothyroidism, etc.), three who did not meet the case definitions, 11 that declined to participate, and 14 eligible patients that could not be matched to a control."
So 102 patient had a diagnosis of ME/CFS and after checking with the CCC criteria, in 24 of them, which is 23.5 %, the diagnosis was wrong. Which shows once again that doctors are not very good at diagnosing ME/CFS.
So once again a study demonstrating physical abnormalities in ME/CFS decides to ignore their own findings because it doesn't fit with their own ideas about ME/CFS for which they do not have any proof and they use psychoblahblah to do as if these physical abnormalities are not important. Whereas these abnormalities are actually "pretty diagnostic of impaired oxidative phosphorylation which is presumably where the "fear " of excercise comes from. Many patients with syndromic mitochondrial diseases fear excercise because their symtoms can worsen dramatically during or following the activity." As GJ rightly wrote on Facebook.