PULLMAN, Wash. — A tiny wearable sensor designed for thoroughbred racehorses can identify horses at elevated risk of catastrophic injury, according to a new study led by researchers at Washington State University.
The sensor records roughly 2,400 data points per second to detail precise stride movements during horse races that are invisible to the human eye. An advanced algorithm analyzes this data, comparing it to patterns from sound, high-performing racehorses and those that suffered fatal musculoskeletal injuries, before assigning each horse a risk score from 1 to 6, with 6 indicating the greatest risk.
Researchers tested the sensors during nearly 30,000 races involving more than 11,800 thoroughbreds at 10 tracks across the United States between July 2021 and May 2024. The study, published in the Journal of the American Veterinary Medical Association, found that horses with a risk score of 6 were 44 times more likely to suffer a fatal injury than those with a score of 1. Horses with a score of 6 made up just 0.4% of starts but represented 4% of all fatalities.
“This technology can help us to intervene before a fatal musculoskeletal injury occurs,” said lead researcher Dr. Warwick Bayly, a professor in WSU’s College of Veterinary Medicine. “We now have the potential to prevent injuries that would end a horse’s career, or even its life, and make racing safer. Our data show focusing on horses flagged with the highest risk scores could reduce fatal injury rates by nearly 20%.”
We now have the potential to prevent injuries that would end a horse’s career, or even its life, and make racing safer.
Dr. Warwick Bayly, professor
Washington State University
The industry has made strides in reducing race-day fatalities — from 2 per 1,000 starts in 2009 to 1.32 in 2023 — but injuries still occur during both racing and training. Necropsy data show 93% of horses that suffered catastrophic injuries had pre-existing bone conditions.
“Every fatal injury is devastating, not just for the horse and connections but for the sport itself,” Bayly said. “Instead of relying on what we can see — which is very little at full gallop — we now have hard data that tells us when something isn’t right.”
WSU began collaborating with the creator of the sensors, StrideSAFE, in 2020, testing the technology at the university’s Hitchcock Research Racetrack, which is the only dedicated research racetrack at a U.S. university. From there, the sensors were deployed at Emerald Downs in Seattle and later at major tracks nationwide, including Saratoga, Belmont, Keeneland and Churchill Downs.
The study also examined other factors associated with injury risk. Age was not found to be a significant predictor, but males were more likely to suffer fatal injuries than females. Horses running shorter races tended to have higher risk scores, and dirt and turf tracks had higher fatality rates than synthetic surfaces.
Bayly is optimistic the sensors can be used to improve the safety of the sport by allowing high-risk horses to be identified early, giving trainers and veterinarians the opportunity to properly assess and address any ailments.
“It’s common to see human athletes wearing biometric sensors to monitor performance and prevent injuries,” Bayly said. “We can now use the same technology to improve the safety of horse racing. If we can identify horses at risk and intervene ahead of time, we not only save lives but also strengthen the integrity and sustainability of the sport.”
Media Contacts
- Warwick Bayly, WSU College of Veterinary Medicine, 509-432-9832, wmb@wsu.edu
- Devin Rokyta, WSU College of Veterinary Medicine communications, 509-335-1911, devin.rokyta@wsu.edu
