Acute ingestion of Ibuprofen does not influence the release of IL-6 or improve self-paced exercise in the heat despite altering cortical activity.

Abstract

The present study tested the hypothesis that ingesting 800mg Ibuprofen prior to self-paced cycling at a fixed rating of perceived exertion (RPE) improves performance by attenuating the release of Interleukin (IL)-6 and its signalling molecules, whilst simultaneously modulating cortical activity and cerebral oxygenation to the brain. Eight healthy, recreationally active males ingested 800mg Ibuprofen or a placebo ~ 1h prior to performing fixed RPE cycling for 60min in 35°C and 60% relative humidity at an intensity of hard to very hard (RPE = 16) with intermittent maximal (RPE = 20) sprints every 10min. Power output (PO), core and mean skin temperatures (Tc, Tsk), respectively, and heart rate (HR) were measured continuously. Electroencephalography (EEG) recordings at the frontal (Fz), motor (Cz) and Parietal (Pz) areas (90s) were collected every 5min. IL-6, soluble glycoprotein receptor (sgp130) and IL-6 receptor (R) were collected at pre-, 30min and immediately post-exercise. Mean PO, HR, Tc and Tsk, and RPE were not different between trials (P ≥ 0.33). At end-exercise, the change in IL-6, sgp130 and sIL-6R was not different between trials (P ≥ 0.12). The increase in α and β activity did not differ in any cortices between trials (P ≥ 0.07); however, there was a significant reduction in α/β activity in the Ibuprofen compared to placebo trials at all sites (P ≤ 0.05). Ingesting a maximal, over-the-counter dose of Ibuprofen prior to exercise in the heat does not attenuate the release of IL-6, nor improve performance, but may influence cortical activity evidenced by a greater reduction in α/β activity.