Effect of restructuring of a racetrack on the occurrence of racing injuries in thoroughbred horses

Summary One of the race courses belonging to the Japan Racing Association was found to have defects in its geometrical design which predisposed racehorses to injury. This racetrack was reconstructed to eliminate these defects. This involved widening of the 3rd and 4th corners, and constructing a gradual curve in the straight stretch between these corners. Furthermore, the composition of the track was changed, and inclines and declines were constructed on the flat stretches. This remodeling of the track decreased the speed of the horses throughout the course, and the incidence of injuries was significantly reduced. Our findings indicate that remodeling of racetracks is effective for reducing the occurrence of racing injuries.