Learn the leg-yield: how your horse moves forward and sideways away from the leg with a slight flexion, in rhythm and without losing the shoulders.
What is the difference between a leg-yield and simply riding on a slant? The honest answer: in the leg-yield the horse steps forward and sideways at the same time, with rhythm and a slight flexion. According to the FEI the exercise shows the horse's suppleness and lateral responsiveness. The horse is almost straight with a slight flexion at the poll away from the direction of movement, so that you can just see the eyebrow and nostril on the inside. The inside legs pass and cross in front of the outside legs [1].
The FEI also stresses: leg-yielding belongs in the training of the horse before it is ready for collected work. Later, together with shoulder-in, it is the best means of making a horse supple and unconstrained [1]. So it is no circus trick but basic work.
The rider's attitude matters too: of lateral movements the FEI says that impulsion is often lost because the rider is preoccupied with bending and pushing the horse sideways [2]. So for the leg-yield too: rhythm and forward first.
For you as a rider the leg-yield is above all a coordination exercise: the inside leg drives sideways, the outside leg holds, the outside hand limits, the inside hand flexes lightly, and your pelvis follows the horse. That is four aids at once, and that is exactly why the exercise often fails on coordination, not on the horse. This is my classification from riding-school practice, not a study finding. So practise the aids one at a time before you combine them.
Before the horse may step sideways it must go forward in rhythm. Ride the leg-yield first at the walk, later at working trot: in FEI tests it is required at working trot [1]. Milestone: The horse stays calm in four-beat on a straight line.
Flex the horse slightly away from the direction of movement, just so much that you see the rim of the inside eye and the nostril [1]. Too much flexion is a fault, because the FEI says bend must never be exaggerated so that rhythm and balance suffer [2]. Milestone: You see nostril and eyebrow but the horse stays loose in the poll.
Apply the inside lower leg behind the girth, briefly and clearly. The outside hand limits, the outside leg holds the hindquarters. Release at once when the horse reacts [3]. Milestone: The horse makes a forward-sideways step without pushing or stumbling.
On the line along the boards the FEI describes an angle of about 35 degrees to the direction of movement. On the diagonal the horse should go as nearly parallel to the long sides as possible, the forehand slightly ahead [1]. Milestone: The horse stays on the rein, the shoulders lead.
End the line, straighten the horse and ride calmly forward. Milestone: The horse stays in rhythm when the sideways aid falls away.
The leg-yield does not replace supervised training. Practise it with an instructor, first at the walk, on non-slip ground and with a horse that is healthy and relaxed. If the horse tenses (tail swishing, teeth grinding, tongue play), the FEI says that may be a sign of nervousness, tension or resistance [5]. Then release and stop. Whether pain is behind it is for the vet to clarify. Never force your horse with constant pressure or a whip: the FEI requires training without abusive or fear-inducing methods [6].
Ride the leg-yield out of a volte: after a 10-metre volte your horse already has bend and attention, and you can introduce the line away from the direction of movement more easily. This is riding-school practice, not a study. What matters is that your horse is straight again after the volte before you give the sideways aid.
According to the FEI about 35 degrees along the boards; on the diagonal the horse should go nearly parallel to the long sides [1]. For beginners a flatter angle with clean rhythm is enough.
It counts as the simpler preparatory exercise: the FEI names it as part of training before collected work [1]. According to the FEI shoulder-in is ridden at collected trot [2].
Many riders have a favourite side. In a study of 16 riders shoulder-in to the right was scored lower in both groups [4]. Let your instructor help without overloading the weaker side.
No, it should stay loose in the poll and in the contact. Resistance or evasion of the hand shows a lack of willingness to cooperate [7]. Then refine the aid, do not apply more pressure.
That cannot be put in a number seriously: neither studies nor rule books name a duration. It depends on horse, rider and training.
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