Introduction: Agouti-Related Protein (AGRP) and Neuropeptide Y (NPY) are neuropeptidesthat involved in appetite control. Few studies have been done on the long-term effects of endurance training on these neuropeptides.The purpose of this study was to investigate the effect of 16 weeks of endurance training on plasma AGRP and NPY levels in Wistar rats.

Materials & methods: 20 male young Wistar rats, with mean ages of 50 to 60 days and the average weight of 158 ± 10 g were randomly divided into two groups: control (n = 10) and training (n = 10). Training program was Endurance training on treadmill for 50-60 min/d, 5d/wk at 25-30 m/min, which is equal to 65-85% VO_2max, for 16 weeks. After 16 weeks, fasting blood sampling was conducted 24 hours after the last training session. t test was used for data analyses. Statistical significance was set at p<0.05.

Findings: The results of the study indicated that endurance training with 65-85% of vo_{2 max} causes a significant increase in plasma AGRP (p=0.001) and non-significant increase in plasma NPY levels in training group compared to control group.

Discussion & conclusions: It seems that endurance training causes a negative energy balance in rats, and to compensate this negative energy balance, plasma AGRP increases significantly and plasma NPY increases insignificantly (increase by more than 23%).