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The present study was performed to investigate the effect of endurance running on muscle protein synthesis. Male Sprague-Dawley rats(n = 49) were randomly assigned to the time course of the treadmill running (VO₂max 75-80%, 1hr). Muscle samples were obtained before and recovery period of the exercise (immediately, 30 min, 1hr, 2hr, 3hr and 6hr from the running) at the soleus muscle for the determination of mammalian target of rapamycin (mTOR), p70S6 kinase (p70S6k), eukaryotic initiation factor (eIF) 4E-binding protein (4E-BP1) and AMPK phosphorylation. Endurance exercise generated a significant increase in mTOR phosphorylation immediately after exercise and the phosphorylation maintained up to 6hr of recovery (∼90%, p=.024). In addition, 4EBP1 phosphorylation was significantly increased at the immediately after exercise and decreased up to an hour recovery. However, 4EBP1 was resumed to increase for 2-3hrs during recovery (∼48%, p=.05). However, Phosphorylation of p70S6K was elevated above rest level throughout the 6hrs recovery and reached peak at 6hr recovery (303%, p=.001). On the other hand, Phospho-AMPK (Thr172) was increased from 30min to 3hr of recovery (p<.05). These results clearly demonstrate that intensitive endurance running result in significant differences in protein signaling of muscle protein synthesis.