The part of your anatomy that contacts the saddle plays a major role in influencing your horse. Here’s how it works.
In dressage, your seat—defined as the area from waist to knees—helps to anchor you in the saddle as you ride. You sit balanced over your two seat bones, and the muscles of your “core” (primarily your stabilizing abdominal muscles, along with those in your pelvis and upper legs) work in concert with your joints to follow your horse’s motion as he walks, trots, and canters.
But the rider’s seat does much more than passively follow the horse’s motion; it is also an aid, and a powerful one.
Along with the leg, the seat usually acts as a driving aid: It helps to create, direct, and regulate your horse’s activity. The way you position your seat bones helps to tell your horse what gait is desired, and the degree to which you allow your pelvis to “swing” and undulate communicates what tempo you want, the size of the steps you want him to take, or even whether you want him to downshift into a lower gait or to halt. And because your horse wants to be in balance underneath you, if you put more weight on one seat bone than the other, he’ll be naturally inclined to reposition his own weight in that direction—and there you have one of the keys to correct corners, circles, turns, and lateral exercises.
So how do you weight a seat bone without contorting, leaning, or sitting crooked in the saddle? By engaging the muscles in opposition. Here’s an exercise that will help give you the feel of how this works.
Sit erect in a chair with your core muscles engaged, feet flat on the floor. Push your right hip bone forward. Can you feel which muscles are working? When I do this, I feel the muscles at the front of my right hip engage. With my core muscles engaged, I can pull my right hip forward and down while stretching my torso up. Lower body stretching down, upper body stretching up — my muscles are working in opposition, pulling in opposite directions on either side of my hip joint. Picture a tall tree, with roots reaching down into the ground, holding fast, and limbs stretching up and out, reaching for the sky. On your horse, your body mimics a tree. Your seat and legs “grow” downward while your upper body stretches upward. You look and feel tall in the saddle.
This movement is subtle. You won’t see much if you look in a mirror, but the feel is unmistakable. Engaging opposing muscle groups is how you avoid rounding forward and collapsing to one side as you weight your inside seat bone. It’s how you maintain an elegant, erect posture in the saddle while giving invisible aids. It’s also how you protect your lower back.
Practice this exercise unmounted until you get the feel of it; then try it on your horse. Your goal is to maintain the feeling of stretching down through your hips and upper legs while simultaneously “zipping up” your abdominal muscles and stretching up with your upper body and sternum. You’ll maintain the engagement of your muscles in opposition while pulling your inside hip forward and down to weight an inside seat bone in preparation for a canter depart, while riding through turns and corners and on circles, in all lateral movements, and while riding flying lead changes at the canter.
The Driving Seat
You can also weight both seat bones in the driving seat. The driving seat does just what its name suggests: it drives the horse forward. Because your upper body stays well back, the driving seat helps the horse remain balanced over his hindquarters.
The classic example of the use of the driving seat is in riding a lengthening, medium, or extension of a gait. By using both seat bones as strong weight aids, the rider says to the horse, “Turn up the volume! Amplify your stride!” Because the weight aids increase in strength
but not in tempo, the rider says: “Take a bigger, stronger stride, not a faster one.” The regularity of the weight aids also tells the horse to remain in the current gait; that’s how he knows you’re asking him to extend his trot stride, for example, instead of asking him to pick up a canter.
Some dressage books explain the use of the driving aids by describing the motion as “scooping” your seat bones forward. At first, I thought that meant I should engage in some sort of pumping action, complete with lower-back undulation. The result was a collapsed midsection, insufficient refinement of the aid, and a sore back — for me and for my horse. I finally realized that scooping the seat bones is less of a shove and more of a pelvic tuck or tilt. In order to do this movement correctly, you must strongly engage your lower abdominal muscles throughout. The abdominals not only prevent your lower back from overarching, but they also create the pelvic tilt.
Unfamiliar with the correct way to perform a pelvic tuck or tilt? Try this easy unmounted exercise. Lie on your back on a firm, comfortable surface, such as a carpeted floor or exercise mat. Bend your knees and rest your feet flat on the floor, arms at your sides. Relax and breathe normally. When your back and abdominal muscles relax, your lower back naturally has a slight arch. You can feel this arch by sliding one hand underneath your lower back as you lie on the floor. (There’s probably enough room to slide your hand under with little difficulty.) This is “neutral spine,” as pictured in photo 1.
Now, thinking “navel to spine,” engage your abdominal muscles. Sink your navel toward your spine and flatten your lower back until it touches the floor. That’s a pelvic tuck (photo 2). Now relax and allow the arch to return to your lower back. Practice alternating between the starting position (neutral spine) and a tucked position. When you think you’ve mastered the action, try it while sitting in a chair, and then on your horse.
Because this slight pelvic tuck is accompanied by a firming and flattening of the lower-back muscles, in their texts some equestrian masters refer to the action as “bracing the back,” which is easily misinterpreted. “Bracing” implies a tightening or clenching action, which produces only an exaggerated swayback and an immediate, unpleasant tightness in the lower back — not the desired effect at all. If the pelvic tilt is done rather firmly and held for just a stride or two, however, it can actually help to slow or stop your horse because it momentarily stops your seat from following his motion. The pelvic tilt is an integral part of the body language that asks your horse for a half-halt and, if held a tad longer, to downshift into a slower gait or even to come to a full halt.
Jennifer Bryant is the editor of USDF Connection and the author of The USDF Guide to Dressage.
Excerpt adapted from The USDF Guide to Dressage © 2006 by Jennifer O. Bryant. Used with permission from Storey Publishing.