Elite racehorses are the very leanest of racing machines, research in Ireland has shown.
The researchers from University College Dublin found fat-free mass was greater for elite versus non-elite horses at all training stages for males, females, and 2- and 3-year-olds, in the assessment of 148 thoroughbreds aged 1-3.
Rita Fonesca, Lisa Katz, Emmeline Hill, and David Kenny set out to determine the effects of age, gender and training on body composition, and the relationship between body composition, physiological measurements and performance in thoroughbred racehorses.
They noted that few non-invasive measures associated with performance assessment were available for racehorse trainers.
In humans, body composition evaluation of superior athletes has revealed less fat, but to date there had been few studies evaluating this in racehorses, the said.
The four, whose study has been accepted for publication in the Equine Veterinary Journal, measured rump fat thickness ultrasonographically in 148 young thoroughbreds aged 1-3 after two, five, and eight months of training.
Speed, heart rate, plasma lactate concentrations and creatine kinase activity were recorded during each fast-work session. Training duration (number of training days) and intensity (number of fast work sessions) were collated for each training period.
Retrospective racing performance was used to categorise horses as elite or non-elite.
Among other findings, they found that fat-free mass was greatest in males at all training stages, and that fat-free mass was greater for elite versus non-elite horses at all training stages for males and females, and 2 and 3-year-olds.
They concluded that while age and training affect body composition, fat-free mass is associated with performance.
Body composition assessment may ultimately assist fitness and performance evaluation, they said.
The relationship between body composition, training and race performance in a group of Thoroughbred Flat racehorses
Rita G. Fonseca, David A. Kenny, Emmeline W. Hill, Lisa M. Katz1