Glucose administration on energy substrates utilization during exercise

Journal of Exercise Nutrition & Biochemistry 2000;4(1):49-60.

Abstract

M
aintaining blood glucose concentration during exercise is important in the athletic field. Therefore, the purpose of this study was the effects of glucose administration on energy substrates utilization during exercise in the untrained (Utr) and trained (Tr) rats. Rats were administered glucose (1.4g/㎏) into the mouth 1h prior to exercise then exercised on the treadmill speed at 20m/min. They were decapitated at pre, 30min, 60min of exercise, and exhausted. Glucose, lactate, FFA, glycerol, glycogen, and liver triglycerides were measured. Glucose concentration was not significantly changed to the groups. Lactate production, however, was significantly increased during the exercise in the Utr. In addition, FFA was significantly increased during the exercise in the Tr. Glycogen utilization ratio during the exercise in the groups were not significantly different, however, the concentration of before the exercise was significantly higher in the Tr. Moreover, exercise time to exhaustion was shorter in the Utr compared with the Tr. These results suggested that glucose administration 1h prior to exercise was possibly maintained blood glucose concentration, however, training-effect was higher compared with glucose-effect during exercise in the groups.