An explanation in an MS book (recommended for TM people to refer to for exercises) talked about the missing myelin which made nerve transmission slower, which therefore required more energy (since the myelin on the nerves makes nerve transmission more efficient). Although I'm not sure if in TM the myelin has actually deteriorated, or if it's just damaged, my assumption would be that it would similarly affect the efficiency of nerve transmission, which would also affect how much (extra) energy would be required to do simple tasks, and therefore cause fatigue.
To me, this is one of the most frustrating things about TM, b/c when you get a bit better, and can walk a little, people think that means you're healed and should be back to work. They can't 'see' how much energy it takes you to do simple tasks, nor understand that by the time I got myself up and ready for work, I'd have to lay down and rest from the exertion of getting ready - to say nothing of if I actually worked for a few hours! :) Oh well - at least we understand each other, which is one of the great things about TMIC!
Sally
