Acute effect of a resistance exercise session on markers of cartilage breakdown and inflammation in women with rheumatoid arthritis.
To assess the acute effect of resistance exercise (RE) on circulating biomarkers of cartilage breakdown and inflammation in women with rheumatoid arthritis (RA). Thirty-four volunteers (17 with and 17 without RA), participated in a 25 min RE session (knee extension, knee flexion, hip abduction and hip adduction) with one set of 12 repetitions at 50% of one repetition maximum (1RM) and one set of eight repetitions at 75% of 1RM. Blood samples were collected 30 and 5 min before, immediately after and 1, 2 and 24 h after the session. We used analysis of variance for repeated-measures with Bonferroni adjustments to assess differences between groups over time. In both groups we found significant changes in interleukin (IL)-1 beta (P = 0.045), IL-1 receptor antagonist (IL-1ra) (P < 0.001), IL-10 (P = 0.004), IL-6 (P < 0.001) and cartilage oligomeric matrix protein (COMP) P < 0.001) in response to exercise, but no changes in tumor necrosis factor-alpha and C-reactive protein levels. We found no differences in the responses of the two groups to the session, except for COMP levels, which are more sensitive to exercise and rest effects in RA patients. Women with and without RA have similar changes in response to a RE session in levels of inflammation biomarkers, but not of cartilage breakdown. IL-10 and IL-1ra increased after the RE session, indicating that RE may have an acute anti-inflammatory effect. Additional studies are necessary to clarify if repeated RE sessions can have long-term anti-inflammatory effects and the possible clinical repercussions of this cartilage breakdown characteristic in response to exercise in RA patients.