Journal of Applied Physiology, Vol 72, Issue 3 836-841, Copyright © 1992 by American Physiological Society
Effect of competition on performance of thoroughbred racehorses
J. D. Harkins, S. G. Kamerling and G. Church
Department of Veterinary Physiology, Pharmacology, and Toxicology, School of Veterinary Medicine, Louisiana State University, Baton Rouge 70803.
The effect of competition and the influence of age and sex on performance
were examined in a study of 18 Thoroughbred racehorses. The horses
performed two solo and two competitive runs at 1,200 and 1,600 m for a
total of eight runs. No group ran faster during competition, which may have
been a reflection of the quality of horses used for this study and their
susceptibility to stress-induced impairment of performance. Males showed no
significant difference between competitive and solo run times, whereas
females were consistently slower during competition. Males ran
significantly faster than females in all runs. There was no difference in
run times due to age, which may have been due to the high mean age (5.9 yr)
of the group. The slower competitive run times may have occurred because of
an earlier onset of fatigue when compared with solo runs. Plasma lactate
was significantly greater for the 1,200-m competitive than for the solo
runs.
