I was diagnosed with mild Graves Disease about 18 months ago and although my blood test results have stabilised for several months and am only taking one carbimazole tablet (5mg) per day, I still get aching thigh muscles when walking hilly areas or up stairs. My specialist says that it has nothing to do with the Graves now (probably from aging! I'm 66). I can walk upto 30 mins on flat ground but then have to sit down from extreme tiredness. Anyone else experiencing this???? Thanks. (I'm live in the foothills of Adelaide, South Australia so have to drive to a suitable flat area to walk).