Thoroughbred racehorse performance is unaffected by the sex of the rider, the findings of fresh research suggest.
Scientists detected no obvious effect from the rider’s sex on either racehorse physiology or performance in a study involving more than 500 Thoroughbreds.
Male and female jockeys have competed against each other in Thoroughbred racing in most major racing nations for decades.
Doctoral student Charlotte Schrurs (PGDip VetPhys, MSc) led a study seeking to identify training-related performance differences in Thoroughbreds linked to the sex of the jockey.
Schrurs and Physiology Professor David S Gardner DSc, both with the University of Nottingham Veterinary School in England, collaborated in the study with Guillaume Dubois PhD, scientific director of Arioneo Ltd, which developed a bespoke exercise tracking device for horses, and equine sports medicine specialist Dr Emmanuelle van Erck-Westergren PhD.
Their findings are currently published as a pre-print, but have been submitted to the journal Scientific Reports.
The researchers monitored 530 Thoroughbred racehorses, aged 2 to 7, from the yard of Ciaron Maher Racing in Victoria, Australia. The horses were ridden by 103 different work riders.
The riders, comprising 66 men and 37 women, completed 3568 work-outs between them across three track surfaces – sand, turf and fibre. Of the riders, 43 were current or past registered professional jockeys.
Arioneo Ltd’s dedicated fitness tracker, dubbed the Equimetre, was able to simultaneously record variables such as speed, stride length, stride frequency, the horse’s heart rate and the rate of recovery. This tracker was specifically designed to monitor horses during their daily exercise routine with advanced data analysis services.
The data enabled the researchers to objectively report the effect of the rider’s sex on racehorse cardiovascular (heart rate, heart rate recovery) and biomechanical parameters (stride length and frequency) at various exercise intensities, ranging from a slow canter to a hard gallop.
Schrurs and her fellow researchers found that the sex of the rider did not influence racehorse speed or stride length at any training intensity.
Heart rate and peak heart rate predictably increased with training intensity, with no discernible difference according to the sex of the rider.
However, heart-rate recovery after exercise did appear to be influenced by rider sex in what the researchers dubbed a curious finding. It was observed only when the usual training intensity on each surface – grass or sand – was reversed, suggesting an interaction between racehorse anticipation of exercise and the sex of the rider.
Male work-riders, more so than female, perhaps anticipated the expected training intensity (for example, a gallop on grass) and their proposed anticipation was transmitted faithfully to the horse, who responded with a higher or lower heart rate.
Further work is needed, however, to confirm this effect, they said.
However, when considered across all training sessions, no difference in expected recovery rates of racehorses was noted between male and female jockeys.
The authors noted that Thoroughbred racing is steeped in tradition dating back to the 18th century in Britain. However, it was not until the mid to late 20th century that the first women’s races were held. Today, more than 90% of participating jockeys in most racing nations are men.
This, they said, likely reflects an unconscious bias toward male jockeys being, on average, physically “stronger”, supposedly able to push horses harder, and thus performing better in races than women.
This decade has seen a marked increase in the participation of female jockeys at an elite level in racing.
Last year, Irish jockey Rachael Blackmore made history by winning several high-profile races.
It is clear, the researchers said, that the tide is turning. Owners and trainers are choosing female jockeys for their horses more often.
Success stories such as Blackmore’s are shaping global betting behaviours on the racetrack, challenging the public’s confidence in the ability of male or female jockeys to win big races.
In Britain and Ireland, previous research has pointed to an underestimation of the ability of female jockeys to win races, as recorded in betting behaviour.
In racing, a competitive advantage may lie in the ability of a jockey to control the horse, and/or by the weight carried by the horse – that is, the weight of the jockey plus his or her saddle.
Hence, jockeys are weighed in before, and weighed out after, races.
Certain races are handicapped by weight carried and according to predicted ability.
The study team found no meaningful differences arising from the sex of the rider in a training environment, but what about in races? Would a racehorse be more or less likely to win a race based on the sex of the jockey?
Analysing results from 52,464 races, female jockeys had a similar win percentage of total race starts as male jockeys in Britain (women at 10.7%, versus men at 11.3%). In Australia, male jockeys had a slightly higher win percentage (11.0% versus 9.9%), but this was negated when considering a top-three race finish.
Taken together, the researchers found minimal effect of the sex of the jockey on both training and race outcomes.
The study team described their research as the first to scientifically and objectively assess whether the sex of the jockey has an influence on any aspect of racehorse physiology and performance.
“The data,” they said, “convincingly suggest the answer is no and offers a new perspective on the possible balance of elite male and female jockeys on the start line of races.”
Efforts to favour a more inclusive environment would greatly contribute toward equal opportunities and the promotion of fair competition between the sexes in racing, they said.