So there's obviously some sort of problem on a cellular level at least within the muscles if not throughout the body, the metabolic pathways are altered in some way which is resulting in less energy outcome, its not obvious as to why but this seems to be the case right from the start, people experience heavy feeling legs and slowed large scale motor function activation, and when they try to exercise they perform less well particularly in endurance, and feel sleepy etc. There is also a problem with more severe patients where lactic acid builds up quickly when the muscles are used, which seems to have been demonstrated in lab tests. so it seems fair to assume there is some baseline level problem there which does not disappear during times of relative health. Who knows what causes this, antibodies, DNA methylation ? could be anything. The observation I made is that individual muscles are not particularly damaged by heavy usage during times of relative health, but when in an overall crash state, the same muscles are very susceptible to inflammation, it seems to happen simultaneously with the activity, can go from feeling completely normal to an intense ache within about 1 hour. What this makes me think is that the 'crash' is likely a form of mode switch by the body or immune system, in response to toxins which are produced by the underlying problem with the cells which I described, or possibly some sort of stress signalling molecules being sent out by the exerted cells, effectively the crash would seem to be the body going into some sort of 'sepsis' like state, anxiety rises, stress vulnerability, heart rate etc. Now when this happens it seems to compound the underlying / original problem, the bodies energy output seems to drop even further, maybe 50% or 60% more and we are forced to lie very still for a while and move as little as possible, or rather don't particularly feel like moving. I think when we enter that state we are more susceptible to damage, the immune system seems to be overactive at that time, which is what then causes that instantaneous muscle inflammation that I mentioned. The worst state I personally got into was shortly following a period where I was easily entering crashes, some lasting over 1 week, and at the same time there was clear auto-immune activity.