Top Racehorses Have Lowest Body Fat Levels

Greyhounds run faster than bloodhounds; cheetahs faster than lions. The same principle holds true for racehorses: lean beats fat, according to a study conducted at University College Dublin.

The research was designed to determine the relationship between body composition, physiological measurements, and performance in Thoroughbred racehorses. It also measured the effects of age, gender, and training on body composition.

The researchers first conducted ultrasonographic measurements of rump fat thickness in 148 young Thoroughbred horses after two, five, and eight months of training. Speed, heart rate, plasma lactate concentrations, and creatine kinase activity were recorded for each training session. Number of training days and fast work sessions were collated for each training period. Based on retrospective racing performance, the horses were grouped as elite or nonelite. When the researchers related amount of body fat to speed, they found that fat-free body mass was greater for elite versus nonelite horses for both males and females. Fat-free mass was greatest in males at all training stages, and fat-free mass was greater for elite versus nonelite horses at all training stages for males and females in two- and three-year-olds. Age and training were found to affect body composition.

It should be pointed out that horses that are thin because of starvation or illness are not the same as equine athletes that have a very lean but muscular build. Horses in athletic training should not have food withheld in the hopes of making them thin. The goal should be to have a horse that is in top physical condition because of excellent nutrition and a carefully planned training regimen rather than a restricted diet.