The comparison of acute high-intensity interval exercise vs. continuous moderate-intensity exercise on plasma calprotectin and associated inflammatory mediators.

PURPOSE: Calprotectin promotes the release of inflammatory mediators (e.g., monocyte chemoattractant protein-1 [MCP-1] and myeloperoxidase [MPO]) during the innate immune response as a mechanism to augment leukocyte chemotaxis and phagocytosis. Although plasma calprotectin is elevated with traditional continuous moderate-intensity exercise (CME) as an indicator of the inflammatory response, high-intensity interval exercise (HIIE) has been shown to attenuate systemic inflammation while providing similar improvements in cardiovascular health. Therefore, the purpose of this study was to compare plasma levels of calprotectin, MCP-1, and MPO between acute HIIE vs. CME.

METHODS: Nine healthy males (24.67±3.27yrs) were recruited to participate in HIIE and CME on a cycle ergometer. HIIE consisted of 10 repeated 60s of cycling at 90% max watts (Wmax ) separated by 2min of active recovery intensity of interval exercise, whereas CME consisted of 28min of cycling at 60% Wmax . Blood samples were collected prior to, immediately post, and 30 and 60min into recovery following exercise.

RESULTS: Acute HIIE elicited a lower elevation in calprotectin and MPO compared to CME. An increase in MCP-1 was observed across time in both exercise protocols. Furthermore, our analyses did not reveal any significant correlation in percent change (baseline to immediately following exercise) among calprotectin, MCP1, and MPO in neither HIIE nor CME. However, a significant positive correlation was observed in the overall release of calprotectin and MPO across all four time points in both HIIE and CME. Conclusions Our findings indicate that acute HIIE may potentially diminish the systemic release of inflammatory mediators (calprotectin and MPO) compared to CME.