Could changes to the preparation of yearlings before sales ultimately have benefits for their early race training?
A study carried out at New Zealand’s Massey University has found that yearlings who had more hand-walking before yearling sales were less likely to have voluntary training interruptions once they entered race training.
In the study, the most common specific reason given by trainers for voluntary interruptions was to allow a horse to grow and strengthen.
Hand-walking during sales preparation is most often given to train and to modify the behavior of the yearlings, and some stud managers use it to improve the fitness of the horses.
“Yearlings that have been exercised may be or may appear to be more developed than those undertaking less hand-walking and may be better able to withstand training without any voluntary interruptions,” the researchers suggested.
They said further investigation into the effects of early exercise on racing performance was needed, but said their results indicated that there may be an opportunity to modify early exercise programs.
Such changes could ultimately reduce the proportion of horses with interruptions before their first trial, they said, noting that in the current study the percentage of horses reaching their first trial without an interruption was less than 30 per cent.
The researchers, Charlotte Bolwell, Christopher Rogers, Nigel French and Elwyn Firth, followed the fortunes of 114 thoroughbreds in their preparation for yearling sales at New Zealand stud farms and their subsequent training as two-year-olds.
The study, published in this month’s American Journal of Veterinary Research, found that 82 of the 114 thoroughbreds – 71.9 per cent – had an interruption before their first trial. Sixty-five of those interruptions – 79 per cent – were voluntary, while 17 (21 per cent) were involuntary. The most common reason reported for forced interruptions was shin soreness.
The study revealed a significant association between the cumulative number of days off and voluntary interruptions.
“It is speculated that horses perceived as not coping well or not sufficiently strong would be given more days off but still kept in training.
“Similarly, increasing canter distance was associated with lesser risk of voluntary interruptions, suggesting that horses with greater cumulative canter distances may be perceived by the trainers as performing well and continue to be exercised.
“Increased total hand-walking time was significantly associated with decreased risk of voluntary interruptions,” they wrote, “whereas longer cumulative distances at a canter were significantly associated with decreased risk of involuntary interruptions.”
The authors, in explaining the reasons for the study, said it was acknowledged that exercise in young children may result in positive skeletal effects that remain in early adulthood within many fields of sport, such as soccer, hockey, and gymnastics.
“Coaches have recognized the benefit of developing the appropriate skills at an early age, during growth and maturation,” they said. “The mechanisms by which the musculoskeletal system responds to early training exercise in horses have been demonstrated and discussed.
“Various frequencies, intensities, and types of exercise during training of horses have been associated with reductions in the rate of musculoskeletal injury and with measures of improved performance during racing.
“Early conditioning exercise of foals in addition to free exercise at pasture does not result in any harmful effects and has a stimulatory effect on components of the musculoskeletal system.
“In two studies, previously conditioned horses were shown to have an early training advantage, such as being ready for racing earlier, compared with unconditioned horses.
“However, the sample sizes in those studies were too small to enable identification of significant training-associated advantages, suggesting further investigation with a larger number of horses is required.”
Within the racing industry, the exercising of young horses occurs during the preparation of yearlings for sale. The median duration of sale preparations was found to be 12 weeks.
Stud masters used methods such as hand-walking and walking on mechanical horse walkers to train yearlings and stimulate muscle development.
“The differences observed in the type and amount of exercise during sales preparation suggest that because the exposure to exercise varies among young horses, these differences in early exercise could impact future athletic performance.”
The researchers said that, given the body of evidence to support the benefits of early conditioning exercise, they set out to investigate the effect of exercise during sales preparation on the risk of interruptions occurring before the first recognized industry milestone – the first trial – during training for a group of thoroughbreds.
They hypothesized that the cumulative durations of hand-walking and mechanical horse-walker exercise provided to horses during sales preparation would be associated with interruptions during their training as two-year-olds. That proved to be correct.
“Results of a recent study indicate that both voluntary and involuntary interruptions increase the time to and reduce the likelihood of a trial and race start, and there is an association between performing trials and racing at two years of age and future racing performance and success.
“Elements within exercise programs during sales preparations represent factors that could be modified to reduce the proportion of horses with interruptions before their first trial.
“Before this could be done, possible associations between early exercise programs and racing success should be investigated,” they noted.
Bolwell CF, Rogers CW, French NP and Firth EC. (2012) Associations between yearling exercise and interruptions to race training in Thoroughbred racehorses. American Journal of Veterinary Research. 73:1610-6. doi: 10.2460/ajvr.73.10.1610