Study on Changes in Racehorses??Metabolites and Exercise-related Hormones before and after a Race

Physiological changes in thoroughbred racehorses during the race were investigated by measuring concentrations of metabolites and exercise-related hormones before and after a race. The conversion point from anaerobic to aerobic exercise during the race was estimated subsequently. Blood samples were taken from the jugular vein of 53 thoroughbreds at different times -three h before and 45 min after- for measuring the concentrations of glucose, non-esterified fatty acids (NEFA), lactate, uric acid, ammonia insulin, adrenocorticotrophin (ACTH) and cortisol according to the race distance. In accordance with the race distance, each metabolite increased in concentration compared with the level before the race. The level of glucose, in particular, increased from 56.18±3.20 mg/dl before the race to 148.82±8.82 mg/dl after the race for horses that raced 1,400 m, showing a significant increase of 165% (p