IL6 and rheumatoid arthritis: IL-6 concentration significantly increased immediately, 1- and 2-h-post-exercise in both groups (RA immediately post: 44.1 ± 37.6 mg/l, 1-h-post: 43.8 ± 33.9 mg/l, 2-h-post: 27.5 ± 32.5 mg/l; CON immediately post: 38.6 ± 28.2 mg/l, 1-h-post: 37.1 ± 26.4 mg/l, 2-h-post: 17.7 ± 15.0 mg/l; all p ⩽ 0.01), returning to baseline 24-h after the exercise session.