Martingale - EquestrianLife Wiki Safety and misuse
The standing martingale is considered to be more restrictive than the running martingale because it cannot be loosened in an emergency and is illegal in most flat classes. Therefore, at horse shows, the standing martingale is primarily used for jumping over relatively low fences where the horse is less likely to need to raise his head for balance. A horse that trips in a standing martingale can fall more easily because its range of motion is restricted.
Due to the risk of injury to the cartilage of the nose, the martingale strap should never be attached to a drop noseband
. Because of the danger of both nose and jaw injuries, it also should also not be attached to a figure-eight noseband. A standing martingale can be attached to the cavesson (the upper, heavier strap) of a flash noseband, but not to the lower, "flash" strap.
A standing martingale may cause great pain to a horse if misused in combination with certain other equipment. If used in conjunction with a gag bit, a standing martingale can trap the head of the horse, simultaneously asking the horse to raise and lower its head and providing no source of relief in either direction. This combination is sometimes seen in polo, in some rodeo events, and occasionally in the lower levels of jumping.
Overuse or misuse of a standing martingale or tiedown, particularly as a means to prevent a horse from tossing its head, can lead to the overdevelopment of the muscles on the underside of the neck, creating an undesirable "upside down" neck that makes it more difficult for the horse to relax and flex properly. It may also lead to a horse tensing its back muscles and moving "flat," especially over fences, all of which put undue pressure on the horse's spine, reduce the shock-absorbing capacity of the leg anatomy, and can over time lead to lameness. There is also a risk of accidents: If a horse is sufficiently "trapped" by a combination of a too-short martingale and too-harsh bit, the horse may rear or fall down in an attempt to free itself from the source of pain.