No abstract

Many changes occur during physical exercise in plasma levels of metabolites and hormones, such as increased levels of lactate, growth hormone, cortisol and catecholamine. It has been proposed that the skeletal muscle could act as an endocrine organ secreting proteins ("myokines") that may exert effects on distant sites. In fact, several studies have shown that increased circulating levels of interleukin-6 (IL6) is one of the most relevant aspects among the observed plasma changes during an episode of physical activity. During acute exercise, the increase in IL6 concentration exceeded 2-100 times basal values depending on the type, intensity and duration of exercise. In parallel, there was an effect of transient suppression of food intake in the short term through a phenomenon called "exercise-induced anorexia." There are evidences to suggest that IL6 is able to modulate appetite and food intake in the central nervous system, which may be particularly relevant in the short-term regulation of post-exercise energy intake.