PLEASE NOTE: The horse's spine makes complex movements in all three dressage gaits. What the rider feels is the whole system of muscles of the back added to movements of the spine. Only the muscles are animated.
This seat is shown here for the trot (halt diagrams are toward the bottom of this page), but the seat mechanics are the same for the walk. Both gaits share alternating diagonal pairs of legs at some point in the gait cycle. In the trot, the diagonal pair is formed nearly simultaneously. For the walk, the diagonal pair is formed one foot at a time. See the walk movie for details. In the walk, there is a more pronounced side to side swing of the belly, which the rider should follow (learning the coordination) or enhance (more advanced). The motion of the rib cage, documented by direct measurements on the vertebrae of the spine, is a combination of axial rotation and lateral bend.
The canter, an asymmetric gait in which there is a diagonal pair repeated (right diagonal for the right canter, left diagonal for the left canter), places demands on the rider's strength and flexibility of trunk muscling. For all three gaits, a rider should coordinate the seat with the muscle cycles of relaxation and contraction in the horse's back while keeping hands as quiet as is possible. Quiet hands of the INDEPENDENT SEAT depend on relaxation of the upper back muscles so the shoulder blades are able to slide smoothly on the back of the rib cage.
Half halts, requests for the horse to rebalance its center of mass, should be given mainly with the lower body and in the coordination and timing context of each gait.
The independent spiral seat & the "circle (or loop) of aids"
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ABOVE left - Independent seat, receiving hands.
Although a loop may be thought of as continuous, it is useful to begin the aids continuum with the lower leg. A horse that is "ahead of the leg" will be ridden TOWARD ITS BRIDLE or FROM BEHIND. Balance is level and steps in front and behind are nearly equal. |
ABOVE right- Pulling, leaning back, driving seat.
Reversing the loop of aids by pulling with hands has a very different effect on the horse. A horse becomes contracted and/or "behind the leg." It is ridden FROM ITS BRIDLE and trails its hind legs. The horse can be said to be "lion in front and mouse behind." |
In the diagrams BELOW
a) a rider's shoulders remain level as pelvis and legs follow the horse,
b) the rider's center of mass in the lower spine does not shift from side to side, keeping weight aids clear, and
c) the hands are able to quietly receive the effects of aids from the lower body.
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| ABOVE: The rider's pelvis oscillates over the lats as they relax and contract.
In order to keep hands independent of the seat, a rider's ribcage needs to be spread wide in front, using the levator costae muscles (sorry, no shorthand name) deep agains the rib cage instead of pulling shoulder blades back. Pulling shoulders back to expose more chest locks your back and seat. You can check to see that your "chest is wide' with the rib cage muscles by making it wide in front of a mirror and shrugging your shoulder blades up and down. If you cannot move your shoulders without making your chest wide and narrow, then you are using superficial muscles and not the deep rib cage muscles. Exercises to help with freedom of the shoulders, arms and hands are HERE (under construction).
Click on these images to view at full size.
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| ABOVE, RIGHT: Here is a movie to help you visualize how the spiral seat works. I have allowed the rider's upper body to jiggle a bit, because there is inevitably a bit of motion from the horse's gaits transmitted through the rider's body. Flexed elbow joints and relaxed shoulders can minimize disturbances in the rein.
It is not so much that wiggly hands always hurt the mouth, except in cases where a rider pulls (inelastic, stuck contact). Rather, the issue is one of "signal to noise" ratio. Jiggling hands interfere with whatever the horse feels in terms of aids: communication is less precise with unnecessary motions.
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A. The rider's seat from behind. The contracted lat (latissimus dorsi) is darker pink than the relaxed glut (medial gluteal muscle). The red dot which is the horse's spine does not just move up and down: it traces an oval as it would if more than these two alternating frames were shown. This is the "divine swing" if the horse's back is relaxed.
B. Side view of the elastic ring with the scalene (lower neck) and abdominal muscles shown in purple. For the color code of anatomy, see "Riding the Elastic Ring" link at the bottom of the page.
Click on the movie to view at full size. (I am editing the movie to show more symmetry in the rider's pelvis---software framing issue.)
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The LEFT image is a correct, relaxed rider capable of following the muscles of the horse's back.
The MIDDLE image shows a rider with a common serious flaw of the seat: "broken at the waist." This tips the rider to one side or the other and interferes with weight aids (balance) by misaligning the rider's center of mass away from the horse's center of mass. It also pulls one leg away from the horse's side, tempting the animal to ignore a leg. The aids to rebalance (half halts) then do not "go through" or affect the whole horse.
The RIGHT image shows another serious flaw with the seat: toe-out. Because riding with one or both toes out disables (locks) the whole pelvis and makes a rider unable to follow the motion of the horse's back. The rider is only able to clamp, which the horse may interpret as the cue (not an aid, which is a natural movement) for canter. Riders and horses become so used to this cue, that the canter will fail if the rider adopts a correct, relaxed seat. Such a rider will have difficulties riding tests involving variations in canter and flying changes. A tight backside rider on horse trained by a correct rider will be surprised when the horse rushes into a trot instead of cantering. This flaw with the seat should be corrected as tactfully and as soon as possible.
