ANALYTICAL CLINICAL STUDIES
The relationship between body composition, training and race performance in a group of Thoroughbred flat racehorses
Article first published online: 7 JAN 2013
© 2012 EVJ Ltd
Equine Veterinary Journal
Volume 45, Issue 5, pages 552–557, September 2013
How to Cite
Fonseca, R. G., Kenny, D. A., Hill, E. W. and Katz, L. M. (2013), The relationship between body composition, training and race performance in a group of Thoroughbred flat racehorses. Equine Veterinary Journal, 45: 552–557. doi: 10.1111/evj.12024
- Issue published online: 2 AUG 2013
- Article first published online: 7 JAN 2013
- Accepted manuscript online: 23 NOV 2012 09:51AM EST
- Manuscript Accepted: 9 NOV 2012
- Manuscript Received: 14 NOV 2011
- Research Development Fund
- body composition;
- fat-free mass;
Reasons for performing study
Few noninvasive measures associated with performance assessment are available for racehorse trainers. Evaluation of body composition of superior human sprinters has revealed a lower fat mass (FM), percentage (%) fat and greater fat-free mass (FFM), but to date there have been few studies evaluating this in racehorses.
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.
At 2, 5 and 8 months of training, rump fat thickness (RFT) was ultrasonographically measured in 1-, 2- and 3-year-old Thoroughbreds (n = 148), with FM, % fat and FFM calculated. Speed, heart rate, plasma lactate and serum creatine kinase concentrations 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 nonelite.
FFM was greater in males (P = 0.006) at all training stages. There were no interactions between training duration, intensity, gender and age (P>0.05); all effects were linear. Training duration had a negative effect on RFT (P = 0.0002), FM (P<0.0001) and % fat (P<0.0001) and a positive effect on FFM (P = 0.01). Training intensity had a negative effect on RFT (P = 0.009), FM (P<0.0001), % fat (P<0.0001) and FFM (P<0.0001). FFM was greater for elite vs. nonelite horses at all training stages (P = 0.003), for males (P = 0.05) and females (P = 0.04) and for 2- (P = 0.002) and 3-year-olds (P = 0.02).
While age and training affect body composition, FFM is associated with performance.
Body composition assessment may assist fitness and performance evaluation.