hopples

Hopples are straps or cords fastened between a horse's legs to restrict its gait, particularly used in harness racing to keep pacers moving in the correct lateral stride pattern.

The term also functions as a verb meaning to put such restraints on an animal, or more figuratively, to hobble or impede movement.

The trainer adjusted the hopples before the race.

Unlike hobbles, which prevent an animal from straying, hopples specifically regulate how a horse moves rather than whether it can move at all.