A blood test showing energy production explanation of fatigue meassociation.org.uk/2015/0...
A simple test displaying unplugged/flat batteries feeling I have described for years as we all have no doubt meeting blank expressions.
Medical Research Council have identified six key areas for research
1 Autonomic dysfunction
2 Cognitive symptoms
3 Fatigue (mitochondrial dysfunction)
4 Immune dysregulation (eg through viral infection)
6 Sleep disorders