The effect of a 3 hour session of aerobic exercise on the concentration of muscle GLUT4 protein and glycogen in skeletal muscles of different types, i.c. soleus, red and white gastrocnemius, was evaluated in diabetic and non-diabetic Sprague Dawley rats. Diabetes was induced by 60mg/kg Streptozotocin injection and swimming was performed during 3 hours in animal swimming pools. There were no significant differences in muscle characteristics between groups (diabetic or non-diabetic groups). Insulin concentration was lower in the DMEX(Diabetes Mellitus Exercise) group (50.46±24.20pmol/l) compared to the NDMEX(Non Diabetes Mellitus Exercise) group (132.40±18.20pmol/l) and glucose concentration was higher in the DMEX group (692.2±45.4mg/dl) than in the NDMEX group (156.2±7.0mg/dl, p<.05). GLUT4 and glycogen concentrations were significantly different between groups and were significantly affected by exercise. GLUT4 after exercise was higher in red gastrocnemius (113.46±19.84%) and white gastrocnemius (58.68±14.46%) than control (p<.05). Glycogen concentration after exercise in DMEX group was higher in white gastrocnemius than soleus (p<.05). There was no change in GLUT4 or glycogen in soleus. In summary, this study has shown that prolonged exercise using the present animal model increases muscle GLUT4 and decreases the glycogen concentration of skeletal muscle. But the effect of exercise on GLUT4 and glycogen concentration are affected by diabetes, skeletal muscle composition and specific muscle recruitment.