Exercise and metformin have both been found to enhance insulin sensitivity in vivo. Therefore, the purpose of the study was to determine the effect of post-exercise metformin administration on muscle glycogen storage in vivo condition. 30 Sprague-Dawley rats were evenly divided into 3 groups: control (C), exercise (E), and exercise-metformin (EM). Metformin was orally provided 500 g daily for 5 days. Exercise protocol consists of 3 h X 2 swimming. Under fasted condition, rats were provided 1 g (50% V/W) glucose. Blood glucose was measured 30 min after oral glucose intubation. 5 h after exercise, muscle glycogen levels in red and white portion of the quadriceps muscle were measured. We found blood glucose concentration in EM group was significantly lower than the rest of groups C: 106±4.52 E: 92.7±3.95 EM: 77.4±4.79 mg/dl, p<.05). Glycogen supercompensation was only observed in the exercised muscle without metformin treatment. Furthermore, metformin did not enhance muscle glycogen storage. In soleus, both exercise and metformin did not cause glycogen supercompensation. In conclusion, post-exercise metformin treatment did not enhance muscle glycogen storage.
Exercise and metformin have both been found to enhance insulin sensitivity in vivo. Therefore, the purpose of the study was to determine the effect of post-exercise metformin administration on muscle glycogen storage in vivo condition. 30 Sprague-Dawley rats were evenly divided into 3 groups: control (C), exercise (E), and exercise-metformin (EM). Metformin was orally provided 500 g daily for 5 days. Exercise protocol consists of 3 h X 2 swimming. Under fasted condition, rats were provided 1 g (50% V/W) glucose. Blood glucose was measured 30 min after oral glucose intubation. 5 h after exercise, muscle glycogen levels in red and white portion of the quadriceps muscle were measured. We found blood glucose concentration in EM group was significantly lower than the rest of groups C: 106±4.52 E: 92.7±3.95 EM: 77.4±4.79 mg/dl, p<.05). Glycogen supercompensation was only observed in the exercised muscle without metformin treatment. Furthermore, metformin did not enhance muscle glycogen storage. In soleus, both exercise and metformin did not cause glycogen supercompensation. In conclusion, post-exercise metformin treatment did not enhance muscle glycogen storage.