Impulsion is the pushing power (thrust) of a horse, which comes from its desire to move powerfully forward with energy. However, speed does not create impulsion, and a rushing horse is more likely to be "flat" than impulsive. A horse can only have impulsion if its hind legs are engaged and its elastic back allows the power to come through.

Definitions

There are competing definitions of impulsion. The 2007 USDF

United States Dressage Federation

The United States Dressage Federation, or the USDF, is the national membership federation for the equestrian sport of dressage. Running under the USEF, the Federation is committed to education, recognition of achievement and promotion of dressage in the United States.Founded in 1973, the USDF now...

 rule book defines it as "...Thrust. Releasing of the energy stored by engagement. The energy is transmitted through a back that is free from negative tension and is manifested in the horse's elastic, whole-body movement. The classical dressage

Classical dressage

Classical dressage evolved from cavalry movements and training for the battlefield, and has since developed into the competitive dressage seen today...

 trainer Nuno Oliveira

Nuno Oliveira

Nuno Oliveira is widely acknowledged as a master of the art of dressage.Nuno was born in Lisbon on June 23, 1925. He studied riding under Joaquim Goncalves de Miranda, in the style of the riding academy of Versailles. A great teacher, he possessed a near-encyclopedic knowledge of equestrian theory...

 described impulsion as, "...a mental and physical state of the horse to obey the rider's demands as fast as possible, to move forward, and to maintain his forward impulsion without support from the aids..." and ""Impulsion means to maintain the energy within the cadence." Another definition is that "[a] horse is said to have impulsion when the energy created by the hind legs is being transmitted into the gait and into every aspect of the forward movement. A horse can be said to be working with impulsion when it pushes off energetically from the ground and swings its feet well forward." The USEF

United States Equestrian Federation

The United States Equestrian Federation is the national governing body for most equestrian sports in the United States. It began on January 20, 1917 as the Association of American Horse Shows, later changed in 1933 to the American Horse Shows Association...

 states, "Impulsion is the term used to describe the transmission of an eager and energetic, yet controlled propulsive energy generated from the hindquarters into the athletic movement of the horse. Its ultimate expression can be shown only through the horse’s soft and swinging back to be guided by a gentle contact with the rider’s hand."

In competitive dressage

Dressage

Dressage is a competitive equestrian sport, defined by the International Equestrian Federation as "the highest expression of horse training." Competitions are held at all levels from amateur to the World Equestrian Games...

 circles, impulsion is defined by the German Training Scale, which states that impulsion is only possible in gaits

Horse gait

Horse gaits are the various ways in which a horse can move, either naturally or as a result of specialized training by humans.-Classification:...

 having a moment of suspension, such as the trot

Trot (horse gait)

The trot is a two-beat diagonal gait of the horse, where the diagonal pairs of legs move forward at the same time. There is a moment of suspension between each beat....

 and canter

Canter

The canter is a controlled, three-beat gait performed by a horse. It is a natural gait possessed by all horses, faster than most horses' trot but slower than the gallop, and is used by all riders. The speed of the canter varies between 16-27 km/h , depending on the length of the stride of the horse...

, but not the walk. This is the current position of the USDF. Others differ, however. Oliveira described impulsion as necessary at all paces: "If your horse goes from walk to trot without changing the head and neck position, the walk had good impulsion." Outside the world of competitive dressage, impulsion is considered necessary at all gaits, encouraged in gaited horses, and in horses used for western riding

Western riding

Western riding is a style of horseback riding which evolved from the ranching and warfare traditions brought to the Americas by the Spanish Conquistadors, and both equipment and riding style evolved to meet the working needs of the cowboy in the American West...

. Impulsion at the walk is encouraged and judged in many lower level dressage and combined driving

Combined driving

Combined driving also known as Horse Driving Trials is an equestrian sport involving carriage driving. In this discipline the driver sits on a vehicle drawn by a single horse, a pair or a team of four. The sport has three phases: Dressage, Cross-country Marathon and Obstacle Cone Driving and is...

 competitions that do not necessarily follow the current trends in international judging.

Purpose and requirements

Impulsion is very important in all equestrian

Equestrianism

Equestrianism more often known as riding, horseback riding or horse riding refers to the skill of riding, driving, or vaulting with horses...

 disciplines, because good impulsion allows the horse to effectively utilize the power in its hindquarters.

Impulsion is particularly important in dressage

Dressage

Dressage is a competitive equestrian sport, defined by the International Equestrian Federation as "the highest expression of horse training." Competitions are held at all levels from amateur to the World Equestrian Games...

. It not only makes the horse's gait more elastic, light, and expressive, but provides the animal with the power needed to perform the required movements. This is especially true for those requiring collection

Collection (horse)

Collection is when a horse carries more weight on his hindlegs than his front legs. The horse draws the body in upon itself so that it becomes like a giant spring whose stored energy can be reclaimed for fighting or running from a predator...

, such as passage

Passage (dressage)

The passage is a movement seen in upper-level dressage, in which the horse performs a highly elevated and extremely powerful trot. The horse is very collected and moves with great impulsion....

, piaffe

Piaffe

The piaffe[p] is a dressage movement where the horse is in a highly collected and cadenced trot, in place or nearly in place. The center of gravity of the horse should be more towards the hind end, with the hindquarters slightly lowered and great bending of the joints in the hind legs...

, pirouette

Pirouette (dressage)

A Pirouette is a French word for the Ballet reference, "to whirl about."A pirouette is a two-track lateral movement asked of a horse in dressage, in which the animal makes a circle with its front end around a smaller circle made by the hind end...

, tempi changes. In jumping

Show jumping

Show jumping, also known as "stadium jumping," "open jumping," or "jumpers," is a member of a family of English riding equestrian events that also includes dressage, eventing, hunters, and equitation. Jumping classes commonly are seen at horse shows throughout the world, including the Olympics...

 poor impulsion is often linked to horses failing to clear obstacles
Good riding is needed to create impulsion in any horse, although some horses may be built in such a way that they can more naturally create impulsion (such as those with an "uphill" build). The horse must be forward, yet relaxed, and coming correctly "on the bit

On the bit

The phrases "on the bit", "behind the bit" and "above the bit" are equestrian terms used to describe a horse's posture relative to the reins and the bridle bit. A position on the bit is submissive to the rider's rein aids, given through the bit. When a horse is behind the bit, the head is tucked...

" by coming up through the back. Additionally, a horse must be straight, with "throughness

Throughness

Throughness is a term used in equestrianism to denote an absence of resistance in the horse to the rider's commands.A 'through' horse is perfectly submissive, allowing the rider’s aids to go freely through the animal, with the reins influencing the forehand, and the riders' seat and legs...

." The rider should use correct driving aids

Riding aids

Riding aids are the cues a rider gives to a horse to communicate what they want the animal to do. Riding aids are broken into the natural aids and the artificial aids.-Natural aids:...

, and contain the energy created by the engaged hind legs. Ideally, this is accoumplished through persuasion of the horse, not bullying.

Impulsion occurs in all gaits

Horse gait

Horse gaits are the various ways in which a horse can move, either naturally or as a result of specialized training by humans.-Classification:...

: the walk, the trot

Trot (horse gait)

The trot is a two-beat diagonal gait of the horse, where the diagonal pairs of legs move forward at the same time. There is a moment of suspension between each beat....

, and the canter

Canter

The canter is a controlled, three-beat gait performed by a horse. It is a natural gait possessed by all horses, faster than most horses' trot but slower than the gallop, and is used by all riders. The speed of the canter varies between 16-27 km/h , depending on the length of the stride of the horse...

 and even the ambling

Ambling

The term amble or ambling is used to describe a number of four-beat intermediate gaits of horses. All are faster than a walk but usually slower than a canter or gallop...

 gaits of gaited horse

Gaited horse

Gaited horses are horse breeds that have natural gaited tendencies, that is, the ability to perform one of the smooth to ride, intermediate speed four-beat horse gaits, collectively referred to as ambling gaits....

s. Because the walk has no moment of suspension, it is a difficult gait to perform with impulsion. Impulsion at various gaits may not always appear the same. In the walk, it is seen when the hindquarters are engaged and the gait is "purposeful yet relaxed." The USEF

United States Equestrian Federation

The United States Equestrian Federation is the national governing body for most equestrian sports in the United States. It began on January 20, 1917 as the Association of American Horse Shows, later changed in 1933 to the American Horse Shows Association...

 describes impulsion at the piaffe

Piaffe

The piaffe[p] is a dressage movement where the horse is in a highly collected and cadenced trot, in place or nearly in place. The center of gravity of the horse should be more towards the hind end, with the hindquarters slightly lowered and great bending of the joints in the hind legs...

as follows: "The piaffe must always be animated by a lively impulsion and characterized by a perfect balance. While giving the impression of being in place there may be a visible inclination to advance, this being displayed by the horse’s eager acceptance to move forward as soon as he
is asked."