Horse gait

thumb| An 1878 [[chronophotography sequence by Eadweard Muybridge of a horse in motion]]

Horses can use various gaits (patterns of leg movement) during locomotion across solid ground, either naturally or as a result of specialized training by humans.

Classification

Gaits are typically categorized into two groups: the "natural" gaits that most horses will use without special training, and the "ambling" gaits that are various smooth-riding, four-beat footfall patterns that may appear naturally in some individuals. Special training is often required before a horse will perform an ambling gait in response to a rider's command. The British Horse Society dressage rules require competitors to perform four variations of the walk, six forms of the trot, five leaping gaits (all forms of the canter), halt, and rein back, but not the gallop.

The so-called "natural" gaits, in increasing order of speed, are the walk, trot, canter, and gallop. Some consider these as three gaits, with the canter a variation of the gallop. All four gaits are seen in wild horse populations. While other intermediate speed gaits may occur naturally to some horses, these four basic gaits occur in nature across almost all horse breeds.

In detail, a horse starts a walk by lifting its left front leg (the other three feet are touching the ground). It then lifts its right hind leg (while being supported by the diagonal pair right front and left hind). Next, the left front foot touches the ground (the horse is now supported by all but the right hind leg); then the horse lifts its right front leg (it is now supported laterally on both left legs), and shortly afterwards it sets down the right hind leg (only the right front leg is now lifted). Then it lifts its left hind leg (diagonal support), puts down the right front (lateral support), lifts the left front, puts down the left hind, and the pattern repeats.

Ideally, the advancing rear hoof oversteps the spot where the previously advancing front hoof touched the ground. The more the rear hoof oversteps, the smoother and more comfortable the walk becomes. Individual horses and different breeds vary in the smoothness of their walk. However, a rider will almost always feel some degree of gentle side-to-side motion in the horse's hips as each hind leg reaches forward.

The fastest "walks" with a four-beat footfall pattern are actually the lateral forms of ambling gaits such as the running walk, singlefoot, and similar rapid but smooth intermediate speed gaits. If a horse begins to speed up and lose a regular four-beat cadence to its gait, the horse is no longer walking but is beginning to either trot or pace.

Trot

thumb|right|The trot, a two-beat gait involving diagonal pairs of legs. The two legs with white stockings are off the ground.The trot is a two-beat gait that has a wide variation in possible speeds and averages about . A very slow trot is sometimes referred to as a jog. An extremely fast trot has no special name, but in harness racing, the trot of a Standardbred is faster than the gallop of the average non-racehorse. The North American speed record for a racing trot under saddle was measured at

In this gait, the horse moves its legs in unison in diagonal pairs. From the standpoint of the balance of the horse, this is a very stable gait, and the horse need not make major balancing motions with its head and neck.

Canter and gallop

thumb|right|An [[Andalusian horse|Andalusian performing the canter. The left hind and right fore will land at the same moment, creating three beats in the stride. This horse is on the left lead, as the left rear and right fore are moving together, with the left hind leading the right hind. As the left fore lands, it will be in front of the right fore.]]

thumb|The suspension phase, seen in the canter and the gallop

The canter (called a "lope" in western riding) and gallop are virtually the same gait, differentiated by having three to four beats, depending on speed. The gallop is an accelerated form of the canter that at its fastest adds a fourth beat to what is normally a three-beat footfall sequence.

Canter

The canter is a controlled three-beat gait that is usually a bit faster than the average trot but slower than the gallop. The average speed of a canter is 16–27 km/h (10–17 mph), depending on the length of the stride of the horse. Listening to a horse canter, one can usually hear the three beats as though a drum had been struck three times in succession. Then there is a rest, and immediately afterwards the three-beat occurs again. The faster the horse is moving, the longer the suspension time between the three beats. The word is thought to be short for "Canterbury gallop".

In the canter, one of the horse's rear legs – the right hind leg, for example – propels the horse forward. During this beat, the horse is supported only on that single leg while the remaining three legs are moving forward. On the next beat the horse catches itself on the left hind and right front legs while the other hind leg is still momentarily on the ground. On the third beat, the horse catches itself on the left front leg while the diagonal pair is momentarily still in contact with the ground.

The gallop is the gait of the classic race horse. Modern Thoroughbred horse races are seldom longer than , though in some countries Arabian horses are sometimes raced as far as . The fastest galloping speed is achieved by the American Quarter Horse, which in a short sprint of a quarter mile () or less has been clocked at speeds approaching . The Guinness Book of World Records lists a Thoroughbred as having averaged over a two-furlong () distance in 2008.

Like a canter, the horse will strike off with its non-leading hind foot; but the second stage of the canter becomes, in the gallop, the second and third stages because the inside hind foot hits the ground a split second before the outside front foot. Then both gaits end with the striking off of the leading leg, followed by a moment of suspension when all four feet are off the ground. A careful listener or observer can tell an extended canter from a gallop by the presence of the fourth beat.

==Pace==<!-- This section is linked from Horse -->

thumb|Pace

The pace is a lateral two-beat gait. In the pace, the two legs on the same side of the horse move forward together, unlike the trot, where the two legs diagonally opposite from each other move forward together. In both the pace and the trot, two feet are always off the ground. The trot is much more common, but some horses, particularly in breeds bred for harness racing, naturally prefer to pace. Pacers are also faster than trotters on average, though horses are raced at both gaits. Among Standardbred horses, pacers breed truer than trotters – that is, trotting sires have a higher proportion of pacers among their get than pacing sires do of trotters.

A slow pace can be relatively comfortable, as the rider is lightly rocked from side to side. A slightly uneven pace that is somewhat between a pace and an amble is the sobreandando of the Peruvian Paso. On the other hand, a slow pace is considered undesirable in an Icelandic horse, where it is called a lull or a "piggy-pace".

With one exception, a fast pace is uncomfortable for riding and very difficult to sit, because the rider is moved rapidly from side to side. The motion feels somewhat as if the rider is on a camel, another animal that naturally paces. However, a camel is much taller than a horse and so even at relatively fast speeds, a rider can follow the rocking motion of a camel. A pacing horse, being smaller and taking quicker steps, moves from side to side at a rate that becomes difficult for a rider to follow at speed, so though the gait is faster and useful for harness racing, it becomes impractical as a gait for riding at speed over long distances. However, in the case of the Icelandic horse, where the pace is known as the skeið, "flying pace" or flugskeið, it is a smooth and highly valued gait, ridden in short bursts at great speed.

A horse that paces and is not used in harness is often taught to perform some form of amble, obtained by lightly unbalancing the horse so the footfalls of the pace break up into a four beat lateral gait that is smoother to ride. A rider cannot properly post to a pacing horse because there is no diagonal gait pattern to follow, though some riders attempt to avoid jostling by rhythmically rising and sitting.

Based on studies of the Icelandic horse, it is possible that the pace may be heritable and linked to a single genetic mutation on DMRT3 in the same manner as the lateral ambling gaits. In almost all cases, the primary feature of the ambling gaits is that one of the feet is bearing full weight at any one time, reflected in the colloquial term, "singlefoot".

All ambling gaits are faster than a walk but usually slower than a canter. They are smoother for a rider than either a trot or a pace, and most can be sustained for relatively long periods, making them particularly desirable for trail riding and other tasks where a rider must spend long periods of time in the saddle. There are two basic types: lateral, wherein the front and hind feet on the same side move in sequence, and diagonal, where the front and hind feet on opposite sides move in sequence. Ambling gaits are further distinguished by whether the footfall rhythm is isochronous (four equal beats in a 1–2–3–4 rhythm) or non-isochronous (1–2, 3–4 rhythm) created by a slight pause between the ground strike of the forefoot of one side to the hind foot of the other.

Not all horses can perform an ambling gait. However, many breeds can be trained to produce them. In most "gaited" breeds, an ambling gait is a hereditary trait. A 2012 DNA study of movement in Icelandic horses and mice have determined that a mutation on the gene DMRT3, which is related to limb movement and motion, causes a premature "stop codon" in horses with lateral ambling gaits.

The major ambling gaits include:

• The fox trot is most often associated with the Missouri Fox Trotter breed, but it is also seen under different names in other gaited breeds. The fox trot is a four-beat diagonal gait in which the front foot of the diagonal pair lands before the hind. The same footfall pattern is characteristic of the trocha, pasitrote and marcha batida seen in various South American breeds.
• Many South American horse breeds have a range of smooth intermediate lateral ambling gaits. The Paso Fino's speed variations are called (from slowest to fastest) the paso fino, paso corto, and paso largo. The Peruvian Paso's lateral gaits are known as the paso llano