Horses are made to perform – to be graceful, athletic, powerful and lovely in motion. But not all horses are created equal. Learning how a horse’s conformation affects his performance can help you to choose the best horse for the job and assess the qualities of the animal you already own.

Begin with Balance

The key ingredient for an athletic horse is balance. All his body parts should fit together to create a harmonious whole – that’s proportionality. If one part is too short, long, narrow or deep compared to the other parts, the horse’s balance is thrown off. He will have to compensate for his lack of balance by working harder, taking shorter strides, or carrying his weight differently. A balanced horse has advantages.

When we size a horse up, we need to see him standing squarely on all four feet, not camped under, parked out, or standing with one foot ahead or behind the other. An awkward stance makes it harder to see his proportions and angles. It’s also important to stand him on level ground. Having a handler is helpful to keep the horse standing square while you look at him.

Start with a side or profile view. That allows you to visually divide the horse’s body into thirds. One third is the chest wall to the withers; one third is the midsection; and one third is the point of the hip to the buttocks. If all of these thirds appear equal, your horse is proportionate. If any part has extra length, we prefer to see it in the chest area or hindquarter, not in the back.

A short, strong back is the key to a balanced horse. A long back makes it harder for a horse to carry a rider at fast gaits and predisposes it to muscle strain in the loin area. A slightly long back may give a jumper an edge, but it works against a reiner or cutting horse who has to be agile while making sideways moves.

A short back improves the horse’s natural collection and engagement, which means that his hindquarters and forequarters can work together easily. A short backed horse can more readily shift his weight from the forehand (where 60 percent of it is naturally carried) to the hindquarter in order to sprint, jump, do a rollback, collect his gaits or perform a dressage movement like the piaffe.

We also look at the height of withers and croup to see balance. Most stock type breeds have slightly downhill balance: the croup is a little higher than the withers. Most warmbloods are built uphill, with withers slightly higher than the hindquarters. Thoroughbreds, Arabians and gaited breeds are usually pretty level.

Slightly downhill horses often excel at speed events like racing and sports that require short bursts of speed and agility, like reining or cutting. Uphill horses have an easier time doing highly collected maneuvers like those required in dressage. As long as a horse’s withers and croup are not too unequal in height, his balance is fine.

Proportionality also includes the head, neck and legs. The horse uses his head and neck for balance. The head and neck are levers or balancing arms that he adjusts as he gallops, jumps, or slides to a stop. A long, trim neck is better than a short, thick neck because it provides a longer, more maneuverable lever. The head is typically about two-thirds the length of the neck. The top side of the neck should be twice the length of its underside.

Finally, the horse’s legs should match his body. If you measure a horse from the top of his withers to his elbow, then measure the front leg, from elbow to fetlock, those two areas should be fairly equal. This measurement should also equal the length of his neck, from poll to wither. If this is hard to see on a live horse, take a photograph. If it’s digital, you can print out a copy on typing paper and draw the measurements and angles right on it, using a ruler and pencil.

Structural Correctness

Structural correctness has a lot to do with legs, but it begins with the body angles, especially in the shoulder. Horses need a long, sloping shoulder in order to reach the front legs forward and take a smooth step.

A horse with a 45 degree slope to his shoulder will have a longer, more ground covering stride than a horse with a 55 degree shoulder. He will be more efficient, taking fewer steps to travel the same distance, he’ll tire less easily, and his legs will probably stay sound longer because he creates less stress and strain on his joints. Steep angles in the shoulder make for a short, jarring stride. A steep shouldered horse is actually less agile over uneven ground or when making sudden turns.

The shoulder angle is reflected in the pastern angle. If the two areas don’t match, that will cause more wear and tear on the horse as well. If a steep shouldered horse has a steep pastern angle, at least his angles still match. That horse is better off with a short pastern than with a long pastern, because symmetry improves functionality.

We can’t actually see the horse’s skeleton, but we can see the joints and angles under the haircoat. If you locate the shoulder angle on a horse when his front leg is perpendicular to the ground, you can imagine where the arm (or humerus) is located. This is the bone between the shoulder and the elbow.

When the shoulder blade slopes back, the humerus and forearm can swing fully, and a horse will have more reach with his front legs. He’ll move with a longer stride and create less concussion every time that foot hits the ground. When you draw his imaginary shoulder-humerus-forearm angles, they will be sharper because of the laid-back shoulder and front leg position. The most “ideal” location of the humerus results in the horse’s elbow falling directly below the front of the withers (rather than the back of them).

If the shoulder-humerus-forearm angle is more open, typically over 90 degrees, the horse’s front leg is set further under his body. If this horse also has a steep shoulder angle and/or a short, low set neck, his gaits will be shorter-strided and rougher, putting more wear and tear on his anatomy. He will also be slower and less agile in fast-moving situations, because his center of gravity is pushed more forward than the ideally balanced horse.

When you look at a horse’s hip, draw a triangle. Go from the point of the hip, to point of buttock, to stifle, then back up to hip. This triangle should be almost equal on all three sides, with the line from hip to buttock a little longer. The angle made by this line and the buttock-stifle line should be sharp. We want sharper angles in the hindquarters because this determines the length of stride and agility of the horse.

A sharper (less open) angle at the buttocks end of the triangle gives the horse more forward reach with his hind legs. Just like with the shoulder and front leg, a wide angle in the hindquarter creates a shorter reach of the hind leg underneath the body. The hip joint is what creates range of motion in the hind leg. Driving power and speed depends on the hindquarters. A horse with acute angles and a longer swing to his hind legs can outrun a horse with wider angles and less reach, and he will use less energy doing it.

Every part of the horse’s body affects another part. The more sloping the shoulder angle, the farther back the withers will be on the horse’s body. This positive quality will also correlate with a longer neck and a shorter back. On the other hand, a long backed horse usually lacks enough length in his neck and hip to carry him with good balance. Everything is connected by the principles of balance and proportionality.

Legs Matter

If your horse has good body angles but poor legs, or vice versa, he will have joint stress and problems. Good legs are straight. When you look at the horse’s legs, do so from the side view first. Drop an imaginary line straight down the front leg, bisecting the forearm, knee, and cannon. It should touch the horse’s heel. If the knee falls in front of the line, he’s over in the knee. If it falls back of the line, he’s calf kneed. Either way, his knee will have increased stress, and it will affect the joints above and below it, like the fetlock. It will also affect how he moves.

Drop another line down the hind leg, starting at the buttock, hitting the back of the hock, the cannon bone, and the heel. If the hocks fall inside the line, the horse is posty legged or too straight in the hocks. If they fall behind the line, he’s has too much set to his hocks. Both conditions create extra stress on the hock, which is a large joint and provides the push-off needed for most movements. If the entire hind leg is crescent shaped and the foot is forward of your imaginary line, the horse has sickle hocks. Though not ideal, sickle hocks are usually preferred to posty legs or too much set to the hocks, because the horse gains some natural collection from them.

Next look at the horse from the front, and drop lines through the center of each front leg. Does the line bisect the forearm, knee, cannon, fetlock and hoof? Or do some parts of the leg fall inside or outside of the line? If the horse’s toes point outward instead of straight ahead, he will wing when he moves. If his toes point inward (called pigeon toes), he will paddle. Both types of movement put extra strain on the knee, fetlock and pastern, and cause the hoof to wear unevenly. Most people prefer a paddler to a winger, because winging may cause leg interference. If the legs brush, touch or hit each other, they can be injured, or the horse can even lose his balance and fall.

When you take a rear view, you can drop a line from the buttocks (where the muscle crease lies) downward, through the hocks, cannon bone, fetlock and center of hoof. If the hocks come together, the horse is cow hocked. If they point away from each other, he’s bowlegged. Though such hocks are desirable in draft horses (because of pulling power), they do not help a riding horse. If you can’t have fairly straight hocks, cow hocks are better than a bowlegged horse. The bowlegged or wide set hind leg may have trouble reaching beyond the stifle joint, creating a short, jarring stride and a rough ride.

We mentioned pasterns earlier, and many people overlook the pastern angle. This joint is a big shock absorber for the horse in motion, especially in the front leg, which has one joint less than the hind leg. When the pastern is short and steep, it doesn’t absorb as much concussion, and passes some of that strain to other areas of the leg.

Long pasterns tend to be more sloping than short ones. As a rule, a Quarter Horse will have a shorter pastern than a Thoroughbred or a Tennessee Walking Horse. Focus on the angle: ideal is 45-55 degrees in the front pastern, depending on the horse’s leg and body conformation. Rear pasterns are typically about four degrees steeper.

A long pastern, less than 45 degrees, makes for a smooth ride, but will be prone to breaking down. A steep pastern, over 55 degrees, will create a rough stride and make the horse more susceptible to sidebone, splints and other leg problems.

The pastern angle should match the hoof angle and the shoulder angle. If the hoof angle does not match the pastern angle, the joints, tendons, ligaments and bones of that leg will be stressed.

On good legs, the bone is flat and clean and the joints are tight and chiseled-looking, not meaty or marked with swellings or blemishes. After you’ve visually examined a horse’s legs, run your hand down each one, feeling for bumps, lumps, or uneven places. Most leg problems stem from structural issues, overuse or injury.

Conformation of the legs is reflected by how the horse moves and how long he stays sound and useful. Although many people think conformation is all about “looking pretty,” it is based on the idea of form to function. Because most horses are expected to be athletes, experienced horsemen look for the qualities of form that translate into good performance and functionality.

In Closing

The horse is a natural athlete, gifted with grace, speed, agility and endurance. The more you learn about the horse’s physiology and biomechanics, you more you can appreciate his unique form and what it contributes to function. Take the time to study the conformation of horses you see and analyze their strengths and weaknesses; such practice can make you a better horseman.