Conformation and biomechanics of the Icelandic horse
Icelandic horses are very special, exciting riding horses. They have four or five gears instead of just three, which makes it both challenging and a lot of fun to ride them. They are versatile and can be both wonderful leisure and sport partners.
Small and sturdy as they are, they are also strong and independent, and eager to go forward. They come in the most beautiful colours, with an abundance of mane and tail.
There simply is nothing better than riding an Icelandic horse that is dancing underneath you in a lightfooted, clear beat tölt with waving mane and a swinging tail.
But in the daily practice of riding, this ideal is not always that easy to achieve.
Just like every riding horse, an Icelandic horse needs a foundation of basic dressage training. The horse needs to learn to relax and lengthen the topline and engage the hindlegs. Without a solid training foundation, it’s not possible to develop things like balance, suppleness, lightness, straightness, tempo control and a clear and steady beat in the different gaits. Basic dressage training is also necessary to keep the horse sound, happy and healthy on the long term.
The thing is, dressage training with icelandics basically takes more skills from the rider than dressage training with a threegaited riding horse or pony. The basic gaits in Icelandic horses usually are not as steady and strong as in threegaited horses. The trot can be broken and insecure, and it can be difficult to get the horse to flex at the poll, and relax his back. The canter can be flat and stiff, without much upward movement. The walk is an exception - a lot of Icelandic horses have a good quality walk but in some horses it can be short and a bit pacy.
And then you have tölt. The biomechanics of tölt are very different from those of the basic gaits (except walk, since tölt is comparable to a running walk). Getting the horse to tölt is often not so much of an issue. Getting the horse to tölt in a steady clear beat, in a nice connection, that is: on the bit, in an upward balance, light on the rein, with a supple back and engagement of the hindlegs, is much more difficult.
Tölt with the horse on the bit
Usually, the basic gaits are better in fourgaited horses than in fivegaited horses and therefore, fourgaited horses often are easier to train according to the basic principles of dressage than fivegaited horses. But in general, it always will take time, commitment and a lot of riding skills to ride and train an Icelandic horse properly, to learn him to use his body in a balanced and healthy way, so that he can effortlessly carry the rider, showing all gaits with ease and grace. Things like riding circles with correct lateral bending, good hindleg engagement, lateral movements, riding canter on a circle, tempo transitions in trot without stiffening the back, and collection in general, are not easy with an Icelandic horse. Apart from the lateral ability, which often ‘weakens’ the basic gaits, this is related to some specific conformation characteristics of the Icelandic horse.
In order to explain this, let’s take a closer look at the conformation of the Icelandic horse.
In general, what we are looking for in an Icelandic horse is not so different from what we want to see in a good allround riding horse: an uphill conformation (well-raised with a well-set, slightly rounded neck and high withers), sloping shoulders, a well-shaped back with the deepest point in the middle instead of directly behind the withers, straight legs with strong joints, harmonious proportions. Horses with conformation faults like a low set or badly shaped neck, heavy and/or deep chest, low withers, very straight or hollow back, ill-proportioned (back too long or too short, very short legs, very short forehand of croupe), crooked legs etc. will always be more problematic to ride in the right balance and connection, with a light rein contact, a supple back and engaged hindlegs, than horses with a better conformation. A narrow horse with a small chest and narrow hips will more likely have balance problems and is not a weight carrier. This applies to all riding horses, Icelandic horses just as well as other types of riding horses.
But when you look at more specific conformation traits, there are differences.
Compared to other types of riding horses and ponies, most Icelandic horses have a rather sloping croupe, a relatively short neck and a relatively straight back. These are conformation traits that are typical for the Icelandic horse as a breed. On the other hand, there is a lot of variation in conformation within the Icelandic horse population. You still can find the oldfashioned, sturdy types next to the leggy, elegant sport types.
Apart from that, there are interesting conformational differences between horses with different gait ability. This is one of the outcomes of statistic research by Thorvaldur Kristjansson e.a., published in 2016. It turned out that horses that excelled in tölt, slow tölt and canter had different conformation characteristics from horses that received a top score for pace.
Horses that excelled in tölt, slow tölt and canter had a long neck, long and supple pasterns, a square body format, a relatively short croupe, a wide pelvis (measured by the width of the hip bones) and a hindleg that is more camped under than camped out. These conformation traits facilitate a more collected way of moving, like in slow tölt and, especially, canter.
Horses that scored particularly high in pace had a long and sloping croupe (pelvis), short pasterns, a rectangular body format, and camped-out hindlegs. These conformation traits facilitate propulsion and speed on a straight line.
It’s likely that breeding selection benefits the conformation characteristics that facilitate propulsion and speed on a straight line over the ones that facilitate collected movements, since the emphasis in breeding assessment is on the fast gaits. Gallop and pace are fast by nature, and in trot and tölt a high speed range is rewarded with higher notes. Also, the breeding system promotes fivegaited horses, since fourgaited horses need to compensate the 5.0 for pace.
Photo left: horse with hindleg more camped under (fourgaited)
Photo right: horse with hindleg more camped out (fivegaited)
Besides this, there are conformation characteristics within the Icelandic horse breed that are not really recognised as such, but have a definite influence on the riding abilities.
These characteristics are:
1. Hypermobility of the limb joints
2. Stiffness of the spine
3. Specific hindleg conformation
Hypermobility of the limb joints
Icelandic horses have hypermobile limb joints, though the amount of hypermobility can vary a lot between individual horses. Hypermobile joints are often more shallow and ‘open’ than joints that have average flexibility, and the joint capsules and ligaments are relatively elastic and loose. This makes the joints very mobile in all directions.
Maybe you recognise this: an Icelandic horse, relaxing in the field, with one or more legs placed in impossibly twisted positions, as if they are not properly connected to the body. This is an obvious sign of hypermobility.
Stiffness of the spine
Most Icelandic horses have a relatively stiff spine and a straight back. That means that the range of motion of the thoracic and lumbar vertebrae in all three directions (flexion-extension, lateroflexion, rotation) is smaller than in other types of horses, like warmbloods. It also means that the back muscles are relatively stiff, with a high muscle tone. Especially fivegaited horses with a strong lateral balance can have rather stiff and straight backs.
Specific hindleg conformation
The hindleg of the Icelandic horse has a specific shape. Especially the joint angles are different from what we usually see in riding horses and ponies.
The croupe is, as mentioned above, often rather sloping. That means that the neutral position of the pelvis is somewhat tilted. The hindleg is often ‘camped out’: the joint angles are backward directed and the hock is placed behind instead of straight under the seatbone. As said, this is more obvious in fivegaited horses. The stifle is often not well placed under the mass, and the stifle angle is often quite open, which makes the stifle joint relatively extended. The lumbo-sacral connection is often located behind, instead of above the hip bone.
Camped out: backward directed joint angles, hock behind the seatbone
Are the above mentioned conformation traits functional for riding?
That depends on the perspective you take.
Hypermobility of the limb joints is probably related to lateral ability, since it also occurs in other gaited breeds like Peruvian Pasos.
It’s also suggested that a certain amount of hypermobility in the limb joints facilitates security and agility on an uneven surface, like in Iceland.
Besides that, breeding selection has probably benefited hypermobility since it facilitates the high-wide, expressive movements that the breeding judges and sport riders are looking for in the gaits of the Icelandic horse.
The thing with hypermobility is that it can cause balance problems and brings along the risk of injuries. Very hypermobile horses therefore need to be carefully and specifically trained in order to develop the balance and musculation they need to support their overflexible limb joints.
For the same reason, horses that are very hypermobile cannot considered to be weight carriers – especially not at a young age.
The stiffness of the spine is functional for maintaining a lateral or diagonal movement pattern at high speed.
Especially in fast trot and pace, the horse stabilizes his movements by stiffening his back. Less mobility of the thoracolumbar vertebrae means that the horse needs less active tension of the back muscles in order to stabilize his movements.
In other words, stabilization will then take less effort and less metabolic energy, and the horse will find it easier to maintain high speed in tölt, pace and trot (this is not the case in gallop. In gallop, the spine cannot be very stiff because the movement requires a high amount of flexion-extension of the spine, especially of the lumbo-sacral connection)
It’s also likely that the stiffness of the spine is a compensation for hypermobility of the limb joints.
The disadvantage of this spinal stiffness, apart from the lack of comfort for the rider in trot (and sometimes also in canter and pace), is that it’s more difficult to work on suppleness and elongation of the back muscles. It’s also more difficult to ride correct, well-balanced circles and lateral movements, since lateral flexion is relatively difficult for the horse.
The particular hindleg conformation of the Icelandic horse is functional for propulsion and speed, but it’s not very functional for hindleg engagement and collection. In some Icelandic horses, the stifles are naturally weak and unstable. This can cause problems like intermittent patellar fixation and patellar instability, especially at a young age. Camped out hindlegswith very straight stifles/extended stifle angles are more prone to stifle problems.
What do these conformation issues mean for the daily practice of riding?
In general, in the Icelandic style of riding the emphasis is on energy and speed, not on collection.
As I explained earlier, Icelandic horses are built for speed. Especially fivegaited horses often show better movements when they are ridden in a somewhat higher tempo. It ‘opens up’ the horse, which means that he takes bigger, more powerful steps and moves more freely from the shoulder. A faster tempo on a straight line also creates dynamic stability.
Tofa von der Igelsburg during a breeding assessment
But dynamic stability is not the same as a sustainable, well-balanced and healthy movement pattern.
In order to develop the latter, you need to work on the things that don’t come natural to your Icelandic horse, like refined balance control and coordination, hindleg engagement, straightness, suppleness and lateral flexibility. You cannot train these things in a higher tempo if you and your horse haven’t mastered them in a slower tempo.
I therefore would recommend riding/training a lot in walk, especially with young horses and horses that are not much trained. I always do a lot of training in walk, with every horse, regardless of their age or training level.
Walk is also the best gait to work on improving the connection. You want to be able to maintain a light, elastic rein contact, with the horse flexing at the poll and chewing on the bit. When you activate the horse in the contact, the horse should respond by engaging his hindlegs, without stiffening on the rein and/or pushing himself to the front .
Because of their conformation, being ridden in a stable, elastic connection is more difficult for Icelandic horses than it is for Warmblood (dressage) horses, to whom it comes more natural to open the topline and engage their hindlegs. If you ride both Icelandic horses and warmblood (dressage) horses, you will probably recognise this.
Photo right: Working on lateral flexion in walk
As soon as the horse can be ridden in a nice connection in walk, it’s also easier to improve the connection in trot and canter. If these gaits are not so strong, they will definitely improve if you are able to maintain an elastic connection and engage your horse’s hindlegs. The trot will become more bouncy and less broken, the canter will become more balanced and less flat.
Riding your horse in a good connection in tölt is a process. It’s best not to focus too much on that in the beginning. You and your horse will benefit more from training self-carriage, lightness, rhythm and tempo control.
A very good exercise is to ride gradually from walk to tölt in an upward balance with the reins (slightly) hanging through. You use your seat to stabilize the horse and to control his energy, your legs to give quick, rhythmical, activating aids and you use only very short , subtle, upward-directed rein aids. Doing this, you can play with the tempo and the rhythm, riding from walk towards tölt, speed up a little and slow down again.
From there, you can work towards riding tölt with a more even rein contact and ask for flexion at the poll and more engagement of the hindlegs without losing the lightness and self-carriage. If you are able to do that, you will have much more influence on the quality of the tölt.
Also, if you happen to have a horse that finds it really difficult tot trot under the rider, riding your horse in a good connection in tölt is the gateway to open the horse to trot.
Increasing the rhythm in walk towards tölt with a light rein contact
Riding circles and serpentines in walk, trot and tölt is a good idea, as long as you can keep the horse balanced during the exercise. You’ll only have balance on a circle or a serpentine when you have correct lateral flexion. It’s important to be very precise in this, since a lot of Icelandic horses find this difficult. Try not to work too much with your inside rein, but focus on bending your horse around your elongated inside leg and lowered inside seatbone, and support him with your outside rein and with a well-centered seat –don’t let yourself be pushed to the outside. In general, a well-centered seat is your main aid while working on balance and straightness in your horse.
In tölt, trot and canter, ride big circles in order to make it easier for your horse to maintain good balance. In walk, you can also ride smaller circles.
Horses that are particularly hypermobile, especially the ‘sporty’ types that have these naturally big movements, need to learn to move more ‘modestly’ in order to gain balance and coordination. The way to train this is to ask for a slower tempo in the gaits than the tempo that is easiest for the horse, without losing the hindleg engagement. Alternating between a very slow, controlled walk with very light rein contact and an active, forward walk with the horse stretching forward-downward in the contact is also very useful in training balance and coordination.
Does your horse have instable/weak stifles? Unevenness in stridelength of the hindlegs and occasionally sagging of (one of) the hindlegs might indicate a stifle issue and should not be ignored. Occasionally locking of the stifle is also something you should take seriously. If you see one of these things in your horse , consult a vet or a physiotherapist before you start or continue the training. The horse might need treatment or specific rehabilitation exercises.
If this is not the case, you can work on strengthening the muscles around the stifle, especially the quadriceps muscle. The quadriceps muscle activates (contracts) when the horse pushes his hindleg off the ground. It stabilizes the stifle in an extended position. It also keeps the patella in place when de horse is standing still.
You can strengthen the musces around the stifle by riding the horse in a moderate, steady tempo in trot or tölt (whatever is easier for the horse) over an even, soft (but not too loose) surface on a straight line. Make sure the horse engages his hindlegs all the time, without stiffening or speeding up. You can also do hillwork on moderate slopes in walk or slow tölt.
Avoid riding (small) circles and lateral work untill the stifles are more stable.
Of course, my advice to focus on a slow(er) tempo doesn’t mean that you should not regularly enjoy a nice gallop, fast tölt or trot through the fields or on the track together with your horse. If your horse is sound and in good shape and doesn’t get out of control, and if a bit of speed and Icelandic fire doesn’t make you nervous, it’s good for the both of you!
My last but by no means least advice is to keep on working on your balance and position in the saddle. As an adult rider on a small horse with a fragile balance, you need to be able to keep your balance as centered as possible all the time. If your balance is not centered enough and your upper body is not stable, this will immediately hinder the balance of your horse. A well-centered, balanced seat also enables you to refine your aids, which will definitely be appreciated by your horse.
Riding bareback is really good balance training for the rider
A good way to train your seat and balance is to ride bareback or with a bareback pad. This does wonders for your body awareness and core stability, and apart from that, it’s great fun.
Remember: a horse can only be as good as his rider. A rider is never better than his horse.
©Marieke Mulder 2018
Thorvaldur Kristjansson e.a., ‘Association of conformation and riding ability in Icelandic horses’, Livestock Science 189 (2016) 91–101
Nina M. Waldern, Kinetics and kinematics of the tölt PhD thesis, Equine Department
Vetsuisse Faculty of the University of Zurich 2014