Effects of Resistance Training on Skeletal Muscle GLUT-4 Protein and LDH Isozyme Expression in Rats

Abstract

The purpose of the present study was to investigate the effect of climbing resistance training on GLUT-4 protein and LDH isozyme activities of the soleus and gastrocnemius muscles in rats. Each experimental group was randomly divided into a control group (n=6) and a resistance exercise (n=6) group. Sprague-Dawley rats were made to climb a 180 cm tower for 12 wk. Weight changes in the resistance exercise group were significantly higher than in the control group (p<0.05). GLUT-4 protein expression of the soleus and gastrocnemius muscles was significantly higher (p<0.05) in the resistance exercise group than in the control group. There was no difference in soleus tissue LDHA4 isozyme activity between the groups. In the case of other LDH isozyme, when compared with the control group, the resistance exercise group showed a significantly higher activity (p<0.05). LDHA4 activity of gastrocnemius muscle tissue was not different between the groups. However, the activity of the resistance exercise group of all the other LDH isozymes was significantly higher than that of the control group (p<0.05). In summary, based on the results of this study, over 12 weeks of resistance training, the total body weight of the rats was reduced and the GLUT-4 activity in the gastrocnemius and soleus muscles was increased. In addition, except for LDH A4 all of the other LDH isozymes activities were increased. These results suggest that climbing resistance training affects the balance of body composition, increases LDH B-type isoenzymes and glucose metabolism capacity, and improves mitochondrial function.