LAUSR

HighlightsIL10 and IL6 have anti‐inflammatory effects in whole‐blood cultures.The anti‐inflammatory action of IL10 was more potent than IL6.MICT and to a greater extent HIIT reduced anti‐inflammatory IL10 action.HIIT and MICT differentially affected IL6 function.Short‐term exercise training may decrease anti‐inflammatory cytokine effectiveness. Abstract A key pathological component of obesity is chronic low‐grade inflammation, which is propagated by infiltration of immune cells into tissues and overproduction of pro‐inflammatory cytokines. Cytokines that possess anti‐inflammatory properties, such as interleukin (IL)‐10 and IL6, may also play an important role. This study was designed to determine the impact of short‐term exercise on the anti‐inflammatory action of IL10 and IL6. Thirty‐three inactive obese adults were randomized to two weeks of high‐intensity interval training (HIIT) or moderate‐intensity continuous training (MICT). Fasting blood samples were collected before and after training. Lipopolysaccharide (LPS)‐induced tumor necrosis factor (TNF)‐&agr; production was measured in whole blood cultures in the presence or absence of IL10 or IL6. IL10 and IL6 receptor expression were measured on circulating monocytes, neutrophils, and T cells. HIIT and MICT reduced the ability of IL10 to inhibit LPS‐induced TNF&agr; production, with a greater effect with HIIT (Group × Time and IL10 × Time interactions, p’s < 0.05). This reduction in IL10 function was not explained by altered IL10R1 expression, which was unchanged after training (p > 0.05). HIIT and MICT differentially affected IL6 function (Group × Time and IL6 × Time interactions, p’s < 0.05) with evidence of reductions in the anti‐inflammatory ability of IL6 with HIIT. Neither HIIT nor MICT altered levels of circulating IL10, IL6, or TNF&agr;. The impact of short‐term HIIT and MICT resulted in differential effects on anti‐inflammatory cytokine function. The clinical implications remain to be determined but these novel findings indicate that measuring anti‐inflammatory cytokine action could reveal important immunomodulatory effects of exercise.