The Importance of Engagement

Everyone tells you how important engagement is. But has anyone told you why? To help you understand, let me first explain how a horse moves.

Movement begins, properly, when a horse’s back and hindquarter muscles contract and pull down that portion of his spine between the point of his croup and the top of his tail. This muscle action also rotates his pelvis forward and down, and lifts that interior (unseen) thigh bone toward his body, which closes the hip joint.

When one joint in the hind leg bends, they all bend. That’s just the way it’s made. So when the hip joint closes, the stifle, hock, and pastern all follow suit, and the leg swings forward beneath his body. There the stifle joint opens to let him reach further, until the hoof hits ground.

On impact all the hind joints “give” a little, to absorb the shock but also to rebound that shock into forward thrust. It’s like pushing a spring together then releasing one end. The rebound, plus more muscle action, pushes the hoof against the ground. The equal and opposite reaction moves the horse’s body over and past the hind leg. Joints open and extend, the hoof lifts off, and the process repeats itself.

A properly moving horse uses his forelegs for shock absorption and for support and balance. They aren’t part of his locomotion system at all and aren’t built to take that kind of punishment. But when a horse is allowed to work on his forehand, or the rider is consistently in front of the motion, it channels some of the hind legs’ equal and opposite reaction into the forelegs. The resulting stress can cause any number of lamenesses, depending on how that particular foreleg is built and where its weakest point is.

In a properly engaged horse, as the hip joint closes it swings down, following and using gravity as additional energy for efficient motion. This produces that gentle “tail wagging” motion, viewed from behind, that dressage coaches love so much.

A “leg mover,” a horse unable or untaught to engage behind, does not have his lower vertebrae tucked nor his pelvis rotated. Because of that he can’t begin a step by simply closing his hip joint angle and letting it swing forward and down. He has to lift the hip joint to flex it. This pull against gravity is harder on those hindquarter muscles, creates more stress and fatigue, and lowers efficiency. It also encourages sore backs and hind leg lamenesses. It’s seen as an up-and-down motion of the hip bones when viewed from behind.

Working a horse without engagement allows that lower portion of his spine, between the point of the croup and the head of the tail, to flatten out and in some cases even to point upward. (We’ve all seen this in halter-trained Arabians and other parked-out types.) This pushes the rest of his spine downward, in both his neck and his back, which results in time in an ewe neck and sway back — both caused by careless riding.

And that’s why engagement is so biomechanically important.