Participant's drug regimen was recorded and a clinical examination of the knee joint was performed to evaluate range of motion, deformity, integrity, stability of knee, and presence of synovitis or effusion. Quadriceps motor function was measured using a strain gauge system that recorded muscle strength and voluntary activation during the strongest maximum voluntary contraction (MVC) out of 3 tries. Proprioceptive acuity was determined from the acuity of reproduction of knee joint position sense (JPS) using an electrogoniometer. Functional performance was assessed by the time taken to perform 4 common ADL that were combined to yield an aggregate functional performance time (AFPT). Disability was evaluated using the Health Assessment Questionnaire (HAQ), with higher scores indicating greater disability. Disease activity was determined using the outcomes recommended at the Conference on Outcome Measures in Rheumatoid Arthritis Clinical Trials (OMERACT). Venous blood samples were taken only from the participants with RA to estimate concentrations of 3 pro-inflammatory cytokines (TNF-?, IL-1?, and IL-6). Samples were taken before and after the control period or the rehabilitation for comparison. Fifteen people with RA in the rehabilitation group were selected at random to have additional blood samples drawn immediately before and after exercise in the second and tenth sessions to see if exercising caused an immediate increase in serum pro-inflammatory cytokines. The rehabilitation group participated in 10 exercise sessions (two per week for five weeks) that involved simple, progressive, individually prescribed exercises to increase quadriceps strength, address individual disabilities, and improve balance and coordination using affordable, simple equipment. The sessions included a 5-minute warm-up, 25 isometric quadriceps MVCs (performed in 4 sets of 6 contractions separated by 1 minute of rest), followed by 3 individualized functional exercises and 3 balance exercises.