Influence of different exercise regimes on the proximal hoof circumference in young Thoroughbred horses.
Authors: Decurnex V, Anderson G A, Davies H M S
Journal: Equine veterinary journal
Summary
# Editorial Summary: Exercise-Induced Changes in Young Thoroughbred Hoof Circumference Understanding how training shapes the developing hoof is crucial for injury prevention in young racehorses, yet systematic data on this relationship has been scarce—a gap this 2009 study addressed by tracking proximal hoof circumference changes across training and rest cycles. Researchers measured the circumference of the front hooves (immediately below the coronary band) in 37 young Thoroughbreds weekly throughout their race preparation, with most horses experiencing at least two distinct training periods interspersed with paddock rest. Training consistently reduced proximal circumference by approximately 0.6–0.66 mm per week during intensive preparation, whilst rest periods reversed this contraction dramatically, with circumference increasing by 1.0–1.1 mm weekly (both P < 0.0001). The measurement technique proved reliable, with a repeatability coefficient of 1.8 mm, making it suitable for routine clinical application. For practitioners, these findings suggest that hoof circumference monitoring could serve as a simple, objective indicator of training load and hoof adaptation—potentially flagging overtraining or maladaptation before lameness develops, particularly when expected expansion during recovery periods fails to occur.
Read the full abstract on PubMed
Practical Takeaways
- •Hoof circumference measurement is a simple, practical field method to objectively track hoof shape changes in training horses—useful for early detection of potential pathological changes before clinical lameness emerges
- •Young racehorses in training show predictable hoof contraction (~0.6 mm/week) that reverses during rest periods, suggesting this may be a normal physiological response rather than necessarily pathological
- •Monitor hoof circumference changes as a potential early indicator of training-related stress; progressive or non-reversible circumference loss may warrant investigation into training intensity, farrier management, or hoof health
Key Findings
- •Proximal hoof circumference decreased significantly during training periods at -0.66 mm/week (left) and -0.64 mm/week (right) in the first training period
- •Hoof circumference increased during rest periods at +1.03 mm/week (left) and +1.12 mm/week (right), reversing training-induced changes
- •The decrease in circumference during second training period was smaller (-0.58 mm/week left, -0.57 mm/week right) compared to first training period
- •Weekly measurement of proximal hoof circumference using a tape measure demonstrated adequate repeatability (coefficient 1.8 mm) for monitoring hoof shape changes