Based on these previous findings which suggested the catabolic effect of INS in CNS, we expected that the intranasal administration of INS augments fat oxidation during exercise; however, contrary to our previous expectations, the intranasal administration of INS reduced fat oxidation during exercise in our normal-weight subjects, and this result was the same as that found in peripheral hyperinsulinemia [26]. Here, INS is linked to Hyperinsulinemia.