Abstract

The influence of citric acid ingestion on the performance during repeated treadmill exercise (28+/-1 m/min, incline +15 degrees) was investigated in male rats. Three bouts of exercise were applied, separated by 1 h-intermissions: the first lasted 1 h, the other two until exhaustion. Before experiment and 5 min after the termination of each exercise, the animals were given orally: glucose (Group G), glucose with citric acid (GC), or water (C). In the second exercise bout, Group G exercised significantly longer than Group C. Group GC exercised longer than C, but shorter than G, differences being non-significant. In the third exercise bout all groups showed similar time of exercise. In the second part of the experiment, the animals performed 3 exercises, lasting 1 h each, separated by 1 h rest intervals. Liver and muscle glycogen, blood glucose, glycerol, lactate, and triglyceride levels were measured. The animals from Groups G and GC showed significantly higher post-exercise lactate accumulation and liver glycogen levels compared to Group C. There were no significant differences between Groups G and GC in any parameter tested. These data suggest that ingestion of citric acid does not appear to alter markedly the metabolism and endurance during repeated exhausting exercises. Verf.-Referat