Shoulder-in is a great gymnastic exercise that helps develop a horse’s balance, engagement, and suppleness. 

Traditionally nowadays, it is performed on three tracks, meaning the horse moves laterally with a slight bend through the body, as if positioned on a circle but traveling straight. In a right shoulder-in, for example, the horse is bent to the right, away from the direction she is moving. As you see on picture the inside right hind leg steps on the same line as the outside front leg.

While the three-track shoulder-in is the standard in dressage tests, there is a wide range of variations in angle and bend that can be useful depending on the horse’s needs.
 

Strengthening the Hind Legs

The inside hind leg learns to step toward the horse’s center of mass and bend.

The outside hind leg takes more weight, building strength for collection.

Improving Shoulder Lift and Rotation

It trains the horse to rotate correctly, lifting the withers and allowing freer movement in rib cage and hip.

Done right this stretches the topline and engages core muscles and most importantly:

This gives more SHOULDER FREEDOM.

It is one of the most difficult exercises to get right but when you do your horses rhythm will deepen and everything feels really easy :)

Most common fault is rider asking for too much bend in the neck, causing the horse to fall out of balance and ending up creating less should freedom. Going for shoulder fore, a really small shoulder in is great in the beginning to get a feel for the shoulder influence and how your horse can balance.

And as always: the circle is a good prep for all lateral work. And a good exercise is coming from the track and preparing for doing a circle (a really round circle :) ) if you do that well together, the first steps of shoulder in is there. And playing around with variations of the size of the circle is great gymnastic too. The point of being particular about the shape of the circle is that it gives you a clear reference point while also providing your horse with valuable gymnastics.

In the next part we will look at reward based ways to create this fantastic exercise.