Acute Resistance Exercise at Varying Volume Loads Does Not Enhance Plasma Interleukin-6

Background: Aerobic exercise has been shown to impart anti-inflammatory effects partly through increased secretion of interleukin-6 (IL-6). Still unclear, however, is whether resistance exercise (RE) also enhances IL-6 secretion. Objective: The present study aimed to examine the effect of RE, performed at varying volume loads (VL), on plasma IL-6. Methods: Ten subjects (seven males and three females: age 37.9 ± 11.4 years; height 170.81 ± 11.16 cm; weight 71.36 ± 11.26 Kg.) participated in three randomized RE protocols: high VL (HVL) (5 sets x 20 repetitions at 45% 1-repetition maximum (1-RM), medium VL (MVL) (3x12 at 75% 1-RM), and low VL (LVL) (2x4 at 90% 1-RM) each separated by 96 hours. Capillary blood for IL-6 measurements was drawn immediately pre-exercise, immediately post-exercise, and 1- and 2-hours post-exercise. Results: There were no significant differences in plasma IL-6 between exercise condition (LVL, MVL, HVL) or at any time point (p=0.422 and p=0.870, respectively). Conclusion: Plasma IL-6 levels are not acutely sensitive to RE, regardless of volume load; therefore, any reported anti-inflammatory effect of RE appears to operate outside of the exercise-induced IL-6 pathway.