Arthritis in knees and taking Enbrel, help me!!!

[Joshua Ty]

I have Arthritis in my knees and I take Enbrel(injection into thigh, once a week). I feel like I have lost my muscular endurance in my legs. I live a very active life, but I can't help notice that I feel(in my legs) weak. I don't feel tired, just my legs do. Does anyone have an answer for this? Is this what happens with Arthritis, or is it the medicine, or do I just need to work out harder???

[just me]

Arthritis, also attacks the connective tissue surrounding the joint, this means the muscle is also attacked, and can cause sore aching muscles. I suffer this as I have Seronegative R.A with Chronic pain which all meds are failing with me so far.