Biomechanics of the Canter and Gallop
The canter and the gallop are arguably the same gait performed at different speeds, with the speed causing dissociation and differing beats (three-beat canter, four-beat gallop). (Clayton and Back, 2013, p. 91) In many parts of Europe, there is no word for canter and the two gaits are considered the same. This paper will discuss both gaits in the context of their similarities and differences in both form and function.
Footfall Sequences
The canter and gallop both have “leads,” and show the same characteristics of all asymmetrical gaits. The footfalls are not evenly spaced chronologically, resulting in footfalls occurring as couplets, alternating between long and short intervals. (Clayton, 2004, p. 164). The canter is a three-beat medium speed gait used in all sport-horse disciplines, but not in racing. It is an asymmetrical gait in which one hind limb trails while the opposite forelimb “leads,” and the other diagonal limb pair moves more or less in synchronicity. There is a period of suspension before each stride. (Pilliner et. al. 2002, p. 121). The footfall sequence of the right lead canter is LH, RH-LF, RF.
The gallop is a four-beat gait, and is the fastest of all equine gaits. It has a transverse sequence of footfalls (the limb placement crosses the body axis). On the right lead it would be LH, RH, LF, RF. Front and hind limb pairs are placed as couplets. As with the canter, the aerial phase follows the lift-off of the leading (inside) forelimb. (Clayton, 2004, p. 183).
Dynamic and Static Equilibrium
The canter and gallop highlight the concepts of static vs. dynamic equilibrium, which are important biomechanical terms. When a horse moves, it is in dynamic equilibrium (as opposed to static equilibrium, which is the balance of the horse at rest). As the horse moves forwards at increasingly faster speeds, dynamic equilibrium allows it to catch itself as the center of gravity falls forwards and propel the body forwards. The faster the horse is moving, the more important it is for the horse to have well-developed dynamic equilibrium. The slower the gait, the more support is needed from hooves on the ground and the greater the tendency to rely on static equilibrium. The gallop and canter rely on dynamic equilibrium far more than the collected trot, for example. During both the canter and the gallop, the leading forelimb catches the horse’s body weight and propels the horse into the suspension phase, assisting dynamic equilibrium. (Pilliner et. al. 2002, p. 140).
Biomechanical Distinctions of the Gallop
The biomechanical distinctions between the canter and the gallop are slight. The gallop is the faster gait, and as a consequence the hooves are placed on the ground separately (creating four beats). This is an exaggeration of the dissociation sometimes seen in the canter between the leading hind limb and the trailing forelimb (in the right lead canter, RH-LF). (Clayton, 2004, p. 186) The gallop has an almost identical sequence to that of the canter. The most noticeable biomechanical distinction occurs in the use of the forequarters and flexion of the spine. When galloping, a horse relies on its forelimbs for propulsion as much as it does the hind limbs. (Pilliner et. al. 2002, p. 149).
The gallop is in no way a collected gait; the center of gravity shits forwards and back to center but not towards the hindquarters. The forelimbs are needed for propulsion to increase the suspension phase. The suspension phase is essential to the gallop for two reasons: it allows the horse to recover its equilibrium and to get its hind feet underneath its body to begin the next stride. To recover its equilibrium, the horse must lift off the ground so that its viscera can move back away from the lungs and it can inhale. To move its hind feet well underneath its body, the horse must be high enough in the air that there is enough time to accomplish this.
The gallop has a very interesting characteristic wherein the horse’s respiratory rate is linked to the stride rate. This is called locomotory-respiratory coupling. Because the horse’s body is so athletically engaged at such a fast pace, this ensures that the respiratory and locomotory muscles do not interfere with each other. When the forelimbs and the head and neck lift, the gut moves back, giving the horse room to breathe in. The horse breathes out when the forehand lowers and the gut shifts forwards again, compressing air out of the lungs. (Pilliner et. al. 2002, p. 140).
The spine also flexes slightly during the suspension phase of the gallop in an almost muscularly identical movement as collection (the different being the level of forward impulsion generated). The croup flexes around the lumbosacral joint as the hip flexors contract and the longissimus dorsi and middle glutes relax. The spine is stabilized against potential sideways movement by the iliocostalis, longissimus, spinalis, and mutifidus muscles. (Pilliner et. al. 2002, p. 144) As the hind limbs push the horse forward (first the trailing hind limb then the leading hind limb) the sacral curve flattens, and the longissimus dorsi and middle gluteals contract. (Ibid. p. 147).
The less time between the two hind feet impacting the ground during the gallop, the more effectively they are able to create forward impulsion and better dynamic balance. However, this narrows the potential base of support that the hind limbs can provide. This is countered by the timing of the placement of the front feet, which contact the ground as far apart as possible so that they catch the horse and support the body in forward motion for as long as possible. (Pilliner et. al. 2002, p. 150). In the canter, the separation of the hind legs is emphasized for better static balance as the horse learns collection.
Biomechanical Distinctions of the Canter
A quality canter has many complex characteristics. As in any sport-horse gait, it is light with regular stride rhythm and balance. The hindquarters must be engaged with adequate joint flexion and no hesitation in the placement of the feet. There should be a regular, three-beat rhythm. When a horse is too slow the rhythm becomes four-beat and the suspension is lost (seen in the western lope). (Pilliner et. al. 2002, p. 121) The gait also becomes four-beat when it is moved up to galloping speed, although the suspension is preserved. (Clayton and Back, 2013, p. 91). In dressage, a canter is also judged by the straightness of the horse. The hindquarters should travel directly behind the forequarters, while the head moves in co-ordination with the horizontal movement of the body. The aerial phase of the gait should be extravagant, gathered and well-defined, referred to as “jump.” (Pilliner et. al. 2002, p. 121). This is biomechanically important to the gallop as well.
The canter begins with the trailing hind limb in single stance. For the right lead canter, this means that the left hind leg is the only one in contact with the ground. (Pilliner et. al. 2002, p. 123). This is followed by a brief tripedal stance to create the second beat of the canter. The inside right hind leg is the leading hind limb. The head and neck must raise (or in the well trained horse, the head, neck, and thoracic sling) and the center of gravity moves back to allow the horse to put more weight on the hind limbs. (Ibid. p. 125). The horse then moves to the right diagonal double stance, with the leading hind limb and the trailing forelimb bearing the horse’s body weight as the leading forelimb impacts the ground to transition to the fore tripedal stance. The leading forelimb then takes the entirety of the horses body weight, which acts as a pivot and launches the horse into the air for the suspension phase. (Ibid. p. 128) The suspension phase of the canter is distinct from the suspension see in the trot in that it is a gathered suspension phase, and the horses body collects, the hindquarters drop, and head and thoracic lift and the left hind is positioned to begin the next stride. (Ibid. pg. 129).
Many riders and trainers mistakenly attribute the quality of the canter to the leading inside hind leg. However, it is the trailing outside hind limb that contributes the most horizontal and vertical propulsive forces. At the beginning of each stride it carries the entirety of the horse’s body weight while creating forward impulsion. The diagonal limb pair then supports the horse’s body weight in the middle of the stride. The leading inside forelimb bears the most concentrated ground reaction forces as it catches the horse’s entire body and prepares to transfer the weight into an upward suspension phase. (Blignault, 2009, p. 191). It is my experience that the simplest method of improving the canter is to half-halt the horse during the leading hind single stance to rebalance the horses weight to the haunches and allow the rest of the horses limbs time to extend, which will lead to greater suspension when the horse is launched into the air.
Conformation
The quality the canter and the gallop have a great deal to do with the angulation of the hock. While good angulation of all joints is productive for healthy movement in any gait, the hock is the distinguishing factor in both of these gaits. To achieve maximum forward drive, the hind feet must rotate through an arc after they leave the ground. This power is transferred through the muscles to the hindquarters, pelvis, up through the spine and then to the forehand. A “sickle hock” with too much angulation gives a longer stride at the gallop, as it has a natural advantage to bend up towards the horses abdominals. This is a useful conformation for long distance racehorses, where stride length is just as important as speed. Sprinters often have straight hocks, so the limb swings more from the hip, allowing a faster stride rate. A dressage horse should have a hock with an angle that is neither straight nor sickle, so that it can achieve both collection and extension. (Pilliner et. al. 2002, p. 150)
Changes of Lead
When a horse canters or gallops to the right, they should be on the right lead and similarly on the left lead when tracking left (unless the rider is asking for a counter-canter as is found in dressage). (Pilliner et. al. 2002, p. 121). Young dressage and jumping horses are asked for a “simple change” by decelerating to the trot or walk for a few strides and then re-establishing canter on the new lead, while mature and well trained sport-horses will change in the air during the moment of suspension. Flying changes are quite natural to horses, unlike counter-canter. Highly trained dressage horses are taught to perform “tempis,” or flying changes of lead at every third, second, or first stride. One-tempis are performed only in the highest levels of competition. (Pilliner et. al. 2002, p. 122). Racehorses usually change with the front legs first, while dressage horses are taught to change with the hind legs first so that the change is “clean.” (Clayton and Back, 2013, p. 91).
Both the canter and gallop have the potential for a change of lead, either by descending to a slower gait or changing lead during the suspension phase. The canter is the only gait in which the change of lead is deliberately trained, as racehorses must simply go fast and a change of lead is in no way a requirement for competition as most races are run on large ovals or straight tracks. A change of lead during a race is usually due to the horse experiencing muscular fatigue. The more fatigued the horse, the more frequently lead changes occur. (Pilliner et. al. 2002, p. 141). Racehorses have been observed to change leads as many as eight times per mile to accommodate muscle fatigue and to reduce the effects of centrifugal force as they gallop around curves. (Clayton and Back, 2013, p. 91) Some racehorses will not change lead, but instead will adopt a “rotary” gallop, similar to a “cross canter,” a common fault where the horse moves on one lead behind and another in front. Rotary strides are seen commonly in young horses who do not have the strength or coordination for a clean change of lead, or it can be indicative of back pain and avoidance of an uncomfortable movement pattern. (Clayton, 2004, p. 185).
The Canter in Dressage
Racing is the only discipline which focuses exclusively on the gallop (it is also a factor in the cross-country phase of three day evening). Dressage is the discipline which places the most emphasis on the canter. Four varieties are recognized: working, collected, medium, and extended. There is also the counter-canter, in which the horse moves counter to the established lead (tracking right on the left lead). This is a movement shown in competition and an exercise to improve strength and suppleness in the back. (Pilliner et. al. 2002, p. 131). The types of canter found in dressage vary by speed, which is achieved by varying the length of the strides without disrupting the stride rate. Stride length is varied by adjusting the placement of the trailing hind limb relative to the leading forelimb. For the collected canter, the trailing hind limb has been shown to contact the ground approximately 60cm behind the placement of the leading forelimb in the previous stride. In the extended canter, the trailing hind limb will contact the ground approximately 40cm ahead of the previous placement of the leading forelimb. (Clayton, 2004, p. 187).
Riding the Canter and Gallop
Riding a canter effectively in the seated position of a dressage rider requires immense skill. It is easy to think one has mastered the sitting canter because it feels much more comfortable in comparison to the trot. A common fault is that the rider rocks back behind the vertical on the third beat of the canter, driving the seat bones into the horses back and pushing it on to the forehand. It is better if the rider counts the first two beats of the canter and stays up for the third beat. It is easier to consider that this two beat rhythm is similar to the two-beat forelimb movement of an active walk. (Blignault 2009, p. 191).
Riding the canter in a hunt seat, jump seat, or riding the gallop is very similar for the rider. The rider is in a “two-point” position, with shortened stirrups to stabilize the lower leg position and the rider out of the saddle. The rider must maintain this position over the horse’s center of gravity, moving forward with the horse. The rider’s hands must move skillfully with the horses head and neck to avoid interference with the forward movement. The faster the horse moves, the more skill and strength this requires.
Transitions from Canter[1]
Horses rarely skip gaits in nature. The faster the gait, the more training the horse requires to skip up or down from it. Dressage horses learn this as a necessary part of their training to promote physical coordination and responsiveness to aids. Upward transition to the canter (halt-canter, walk-canter, trot-canter) are reduced in difficulty as the speed increases because the horse is able to use impulsion to move up to canter. Halt-canter is the most difficult. The horse must lift his entire frame off the ground from a standstill. In nature, the horse begins the movement by lifting the head and neck and tightening the topline muscles in an extension pattern to lift the forehand. This is a fault in dressage, so the horse is trained to push powerfully with the trailing hind limb, then lift, and step with the diagonal limb pair. Sometimes the horse will push with both hind legs and launch into the canter if the trailing hind limb does not have enough strength. (Blignault 2009, p. 193-4).
Without the use of the head and neck, the horse’s back and hind leg muscles are put under immense strain. The halt-canter transition is not for young, untrained, or unfit horses. The main muscles used are the hamstrings, gluteals, and longissimus. The neck muscles must contract isometrically rather than extending. (Blignault 2009, p. 195).
Walk to canter is less physically strenuous, but requires great tack on the part of the rider to achieve the correct timing to coordinate limb placements. The horse has to be prepared to take the correct lead. The horses inside shoulder must be ahead of its outside shoulder and the weight on the outside legs. The horse finds this easier with a natural outside neck bend. In competition an inside bend is required to demonstrate strength and balance. The horse is taught to maintain outside balance while bending to the inside. This is also not a movement for unfit horses, although it is required in lower levels of competition. The aid to canter should be given when the outside hind leg is about to contact the ground, so that it becomes the trailing hind limb in the first stride of canter. It is an upward movement as much as a forward movement. (Blignault 2009, p. 197).
Trot to canter is the easiest upward transition, and can be used to build strength. There are two common types of trot to canter transitions. The horse can simply ground the inside forelimb and use it to propel its body into suspension, or it can ground the outside hind leg and use it push into the stride. Neither method affects the quality of the canter that follows, so riders do not usually worry about which limb their horse prefers to use. (Blignault 2009, p. 199).
Downward transitions naturally occur when the horse transforms horizontal propulsion into vertical force by using the forelimbs to brake against the ground. To transition down while on the bit, the horse must move its center of gravity back and use its hindquarters for braking. The natural reaction of hollowing the back and “falling” into the canter is a fault and is not a healthy movement pattern as it does not allow horse to sustainably carry a rider. The more engaged the horse is, the more sophisticated the downward transitions will be. As with upward transitions, the slower the gait that the horse is dropping down to, the more difficult the transition will be. Canter to halt is the most advanced of the downward transitions from canter. (Blignault 2009, p. 203-5).
Faults in the Canter
The most common fault in the canter is the cross-canter, where the horse canters on one lead in front and another behind. When the horse is loose in a field or longing ring, it is often caused by loss of balance or muscle fatigue. Horses rarely canter in circles on their own, so this is difficult for young or inexperienced horses. When a horse cross canters under saddle, it is due to a lack of “thoughtness” in their body, or the rider not allowing the head and neck enough freedom, causing the haunches to swing out in a balance reaction and change behind. It is important to consider that a cross canter could be a signal of pain in the horses body that does not show up in slower gaits. (Blignault 2009, p. 207).
Horses do not naturally canter completely straight. This is considered a fault in dressage. To prevent overreaching, the horse naturally positions it’s haunches inside of the direction it is traveling. Horses are all naturally dominant on one side or the other, which is also a contributing factor to crookedness. To correct this and strengthen the horse’s weaker side, the weak hind leg must be ridden farther under the horses center of gravity. (Blignault 2009, p. 208).
The four-beat canter is almost always a problem caused by the rider. Unlike the four beats of the gallop, which are caused by increased speed and are not a fault, the four-beat canter is caused by lack of forward impulsion. The same dissociation between the diagonal pair of legs as in the gallop occurs when the rider slows the horse without asking for more forward impulsion. This can be corrected by the rider asking for more forward movement. (Blignault, 2009, p. 209-10).
Context of Accompanying Video – The Biomechanics of Canter
I do not ride or train racehorses or eventers, so I do not have access to horses that are being trained to gallop or a safe surface on which to do so. The video that accompanies this paper is therefore only about the canter. I wanted to show the diversity within the gait, even in horses that are being trained for the same discipline, in this case dressage.
Lorca and Hendrix are both young horses (4 and 3 years old). They are both started under saddle, but spend a lot of time working on the ground. I have been working consistently with Lorca since August. Hendrix was started by another trainer this past summer, and has been living out in the field for a few months to give him an opportunity to physically and mentally mature before he is put into a long-term training regimen.
Lorca does not naturally have a good canter. When I first began to work with her, she was very unfit. I do not believe she was ever conditioned properly before she was ridden, because her withers were depressed into her thoracic and her overall musculature was very poor. She did not have good balance. She was used to loading her weight too much to the inside while being longed, and was not built up properly to carry a rider. This caused her back to go into spasms and she developed both bolting and rearing habits in a pain avoidance reaction. Her back was injected by a veterinarian to treat chronic muscle tension before I was given her as a training project.
To teach Lorca to move correctly, I first had to “take her apart.” Meaning I developed her strength and flexibility on the long reins by teaching her to articulate her body and find self-balance. In order to canter, she had to learn to release the muscles along her back and lift her abdominals. As her thoracic sling strengthened, the scapula became unstuck from the surrounding tissue and she was able to move more freely in her body. As she learned that she could move without pain, the bolting stopped. I have never seen her rear. She is now able to fold the joints of her hind legs while dropping her hindquarters to generate impulsion which moves all the way through her body. The flow of energy in her body no longer becomes “stuck” at any one anatomical location.
Lorca still sometimes struggles during her warm-ups before her muscles loosen. She will switch leads, cross-canter, or counter canter to avoid weighting her outside hind leg. As she becomes stronger, this happens less. I am now riding her on a regular basis, but not for more than thirty minutes at a time to avoid muscle fatigue in her back. Her canter is better under saddle because I can more directly influence her balance.
Hendrix is a stunning young horse. He is bred from top dressage bloodlines. He has conformation which is ideally suited to excellent gaits. His mother has a fantastic canter. With slightly more strength, Hendrix will as well. Hendrix also has never been wrecked by his training, physically or mentally. This results in a young horse that is very comfortable in his body and is mentally stable. He is lovely to work with and has a very soft demeanor.
His canter shows the all of the characteristics that make a good canter great. He is supple in his body, and is able to articulate his hind legs to vault him through the air for an expressive gait. He has metronomic rhythm and the gait has three clear beats. This is not a canter that needs to be biomechanically modified in any way, unlike Lorca’s.
Conclusion
The canter and the gallop are the most biomechanically similar of the four common equine gaits. It is understandable that they would mistakenly be considered the same, with the only difference being speed. There has been much more attention paid to the minute characteristics of the canter than the gallop, likely due to the variation seen within the gate and it’s prevalence in all sport horse disciplines. While canter can serve many functions, the gallop is a gait developed only for speed. Therefore the biomechanical research done on the subject is limited in application. Lorca and Hendrix demonstrate the spectrum of the canter in sport horses; Lorca’s has the potential to be truly terrible while Hendrix’s is could be exceptional with continued proper training. It is unfortunate that I do not have an accompanying video for the gallop. It would then be easy to demonstrate that while the two gaits are similar in function, they are vastly different in form, application, and context.
Bibliography
1. Back, Willem, and Hilary M. Clayton. Equine Locomotion. 2nd ed. Saunders Ltd, 2013. Print.
2. Blignault, Karin. Equine Biomechanics For Riders: The Key to Balanced Riding. J. A. Allen, 2009. Print.
3. Clayton, H.M. The Dynamic Horse: A Biomechanical Guide to Equine Movement and Performance. Sport Horse Publications, 2004. Web.
4. Pilliner, Sarah, Samantha Elmhurst, and Zoe Davies. The Horse in Motion: The Anatomy and Physiology of Equine Locomotion. 1st ed. Wiley-Blackwell, 2002. Print.
[1] Transitions from the gallop are not schooled, with the exception of racehorses breaking from the starting gate. In that instance, the horse drops its haunches and pushes powerfully off of both hind feet to initiate the gallop. This is easily observable in any horse race.