Abstract: Objective: To examine the association between the PI3K/Akt/mTOR pathway and the skeletal muscle growth and its potential mechanism responding to swimming training.Methods: 40 male SD rats were divided into control group (C) and training group (T) , and used to establish swimming training models with a 15% weight load.The training adopted interval training protocol with load and training every other day with 8 weeks.The gastrocnemius and soleus muscle were collected and weighed after training, and the protein expression of PI3K, Akt, mTOR and their activated forms were examined.Results: After 8 weeks treatment, no significant was observed in skeletal muscle mass between groups, but the Soleus and Gastrocnemius Muscle Mass Index in training T group increased significantly compared with control group (P<0.05) .Compared with the control group, the ratio of P-PI3K/PI3K, P-Akt/Akt, P-mTOR/mTOR in T group increased with insignificant difference, but the ratio in TR and TRL groups was significantly reduced (P<0.05) .Conclusions: these results suggest that the interval training protocol is helpful to increase the relative muscle hypertrophy, LY294002 and Rapamycin has an inhibition role in the PI3K/Akt/mTOR pathway responding to training.