Changes in Thoroughbred speed and stride characteristics over successive race starts and their association with musculoskeletal injury.
Authors: Wong Adelene S M, Morrice-West Ashleigh V, Whitton R Chris, Hitchens Peta L
Journal: Equine veterinary journal
Summary
# Editorial Summary: Speed and Stride Changes as MSI Indicators in Racehorses Racing Thoroughbreds experiencing declines in speed and stride length across successive race starts show markedly elevated musculoskeletal injury (MSI) risk, with this relationship quantifiable through longitudinal biomechanical analysis. Wong and colleagues analysed 5660 race starts from 584 horses (146 injured, 438 control) using joint statistical modelling to track changes in final-sectional speed, stride length and stride frequency whilst monitoring time-to-injury outcomes. Each 0.1 m/s decrease in speed carried an 18% increased injury hazard, whilst every 10 cm reduction in stride length raised risk by 11%, with particularly steep declines observable approximately six races before injury diagnosis. Notably, injury risk was highest early in racing careers, and a pronounced rate of deterioration in both parameters emerged in the pre-injury window—suggesting these metrics could serve as practical warning indicators. For practitioners, routine measurement and trending of stride characteristics across training and racing calendars may enable earlier identification of subclinical MSI and allow timely intervention, though the authors acknowledge that single-sectional analysis and variable inter-race recovery periods represent limitations in translating these findings directly to training environments.
Read the full abstract on PubMed
Practical Takeaways
- •Monitor stride length and speed trends across multiple races as early warning indicators of impending musculoskeletal injury—declining metrics 6+ races before injury provide a detection window
- •Pay particular attention to younger horses early in their racing careers, as they show the highest MSI risk
- •Implementing longitudinal stride monitoring systems may enable preventative management before injury occurs
Key Findings
- •Risk of MSI increased by 1.18 for each 0.1 m/s decrease in speed over career race starts (P<0.001)
- •Risk of MSI increased by 1.11 for each 10 cm decrease in stride length over time (P=0.01)
- •A marked rate of decline in speed and stride length was observed approximately 6 races prior to injury
- •Risk of MSI was highest early in the horse's racing career