Enhanced insulin sensitivity after acute exercise is not associated with changes in high-molecular weight adiponectin concentration in plasma.

BACKGROUND AND OBJECTIVE The effect of exercise on the plasma concentration of high-molecular weight (HMW) adiponectin (i.e. the biologically active form of circulating adiponectin) and the possible role of HMW adiponectin in mediating the exercise-induced enhancement of insulin action are not known. The aim of this study was to evaluate the relationship between the post-exercise increase in insulin sensitivity and plasma HMW adiponectin concentration. DESIGN AND METHODS We measured total and HMW adiponectin concentrations in plasma using an ELISA kit, and insulin sensitivity using the updated homeostasis model assessment of insulin sensitivity (HOMA2-IS) score in the basal, overnight fasted state, once approximately 12 h after a single bout of moderate-intensity endurance exercise and once after an equivalent period of rest, in 27 healthy men and women (age: 29+/-1 years and body mass index: 24.7+/-0.8 kg/m(2)). RESULTS The HOMA2-IS score was 18+/-7% greater after exercise than after rest (229+/-20 and 196+/-17 respectively; P=0.006), whereas the concentrations of total adiponectin (7.8+/-0.5 and 7.7+/-0.5 mg/l respectively; P=0.597) and HMW adiponectin (3.0+/-0.3 and 3.0+/-0.3 mg/l respectively; P=0.625) were not different. The exercise-induced change in HOMA2-IS score was not related to changes in total and HMW adiponectin concentrations (P>0.3). CONCLUSIONS Changes in HMW adiponectin concentration are not involved in the acute exercise-induced enhancement of insulin action.