Hello, I just want to know if anyone else has ever had this happen. I have myositis, along with many other autoimmune diseases, but right now the myositis, seems to bother me the most. I have been not doing much just hanging in the house, doing normal things, sitdown, then do something and then sit down, usually done by 3 because my body gives out, but had a surprise the other day. Went to a pulmonolgist for something else, they tested me for shortness of breath b y doing a oxygen meter test while taking a six min non stop walk. Well I could not walk the distance. Not because of my oxygen that was fine, it was my legs, my thighs, they burned so bad, and my hips by four mins I was litterly pushing my legs and hips to have me make it through it. I could not believe how bad I was. I guess by not walking distances for so long I have noticed some progression. Also my imuran was lowered in Nov from 200 to 150 and I can not wonder if that had something to do with it too., I swim twice a week for the past two months and am doing fine with that. I am not lazy person, but I can not walk past four mins straight withoug the severe burning and pain,. Does anyone have any ideas about this?