A single bout of downhill running transiently increases HOMA-IR without altering adipokine response in healthy adult women

Abstract

Eccentric exercise-induced muscle damage may cause marked alterations in insulin sensitivity. However, it is not entirely known whether such alterations are also related to changes in adipokine levels. The aim of this study was to investigate the effects of muscle damage due to downhill running on inflammation, insulin sensitivity and selected adipokines related to insulin regulation (adiponectin, visfatin, resistin). Data were collected from 12 healthy adult women. Each subject participated in two trials, 4weeks apart. The first trial was reserved for resting measurements only (control trial), while the second trial involved a 45-min exercise (-15% slope,~60% of VO2max) intervention (exercise trial). Insulin sensitivity (HOMA), creatine kinase activity (CK), delayed onset muscle soreness (DOMS), tumor necrosis factor α (TNF-α), interleukin 6 (IL-6), glucose, insulin, adiponectin, resistin, and visfatin were assessed pre-exercise and 1, 2, 3, and 4days post-exercise and during the same time points in the control trial. Analyses revealed that CK, DOMS, TNF-α, IL-6, insulin and HOMA significantly increased (p<0.05) throughout recovery (days 1-4). Adiponectin and visfatin remained unchanged, while resistin significantly increased (p<0.05) only 2days post-exercise. Visfatin was negatively correlated with HOMA at days 1 and 4 of recovery. Although muscle damage due to downhill running caused a decline of insulin sensitivity, this response was not associated with the changes in adipokine levels.