This study was carried out to investigate the muscle weight and nucleolar organizer region(NOR associated protein synthesis. The healthy rat Tibialis anterior and gastrocnemius muscle loaded with movement by Klitgaard`s weight training model has stained silver chloride. Tibialis anterior muscle is flexor and gastrocnemius muscle is extensor of ankle Joint. Two muscle will be different affect by movement. Ag-NOR technique is a indirect method to measure of the ongoing transcriptional activity of the rRNA gene or their activity. The number of Ag-NORs sites within nucleus may feflect protein synthetic activity and proliferation. Thirty spraque-Dawley adult male rat(200-300g) were divided into control and 3 experimental group were trained for 1. 2. 3 months. Body weight and muscle weight measured at 1. 2. 3 month. The removed muscle fixed by immersion and processed for light microscopy. The result were as follow: 1. Body weight were increased, but muscle weight were decreased with the lapse of time of training. There was no significantly different from the control in tibialis anterior muscle, but, gastrocnemius muscle was significantly different from the control. 2. The mean number of nucleolar organizer regions per nucleus were significantly increased at 3 month in tibialis anterior muscle and 2, 3 month in gastrocnemius muscle. 3. The percent of nucleus include 4 or 5 Ag-NOR was increased with lapse of time of training. Gastrocnemius muscle were more include Ag-NOR than tibialis anterior muscle. The results indicate that gastrocnemius was more affected by