Heather Sansom owns Equifitt.com Equestrian Fitness, offering personalized coaching through clinics and convenient online coaching available anywhere. She also offers a free monthly newsletter, called fittips, and new e-books, Complete Core Workout for Riders and Handy Stretching Guide for Riders, at Equifitt.com.
As riders, when we think of symmetry, we think of one leg seeming longer than the other--in spite of even stirrup leathers, or a shoulder that tends to drop below the other. We also think of slouching forward, leaning back or riding with one hip falling "in" or "out". These are all great examples of the way our body balances itself in the sagital and frontal planes.
Movement in the sagital plane means forward and back, such as your shoulders slouching or your knees creeping forward. Movement in the frontal plan would be side to side, such as your left shoulder dropping, or spine curving left.
Since the goal in riding is to maintain symmetry in motion, body movement outside a nicely vertically stacked symmetrical position usually results in compensating patterns. For example, it's quite common to see shoulders that lean back accompanied by lower legs that creep forward. Your body is trying to distribute your mass in equal portions across the center of gravity. When that center is under your seatbones in the middle of the saddle, your shoulders and heels are in alignment, you are straight. If you shift the distribution of your weight from the center by leaning your shoulders back, your body needs to send an approximately equivalent amount forward to balance you in gravity.
Similarly, when your left shoulder has a tendency to drop, it's quite common to also see a right hip dropping, causing your horse to drift to the right. This is completely counterintuitive if you had been thinking "I lean left so why does my horse drift right." However, when you think about it, the mechanics and physics make sense: your horse listens to your seat before he listens to your shoulders, since your seat weighs more and is in first contact with him.
Another aspect of rider symmetry is your axis. If your spine is your axis, and the ideal is to be vertically stacked with a normal spinal curvature and your shoulders aligned symmetrically over your hips (when dead straight on the horse), then an example of axial rotation would be your left shoulder not only dropping, but also falling back. Typically, a shoulder falling back is often paired with the opposite hip also falling back. Or, the hip on the same side moving forward. If you were to look at your body from the top of your head, you would see your shoulder girdle and hip alignment shifting from straight vertically stacked lines to an "X" pattern.
We use the body's ability for axial rotation on a constant basis when riding because we constantly adjust the angle of our shoulders and hips to bend on whatever curve we want our horse's shoulders and hips to align to. The result would look like a sideways "V" from the top, and the width of the V would depend on the degree of bend. Axial rotation is used in all kinds of daily activities and other sports. Very clear examples would be a golf swing or polo swing. In my area of the world, snow shoveling would be a common example right now. Often the way we use our body's rotational movement ability (or don't) in daily life and other activity creates problems for our riding. We wire our muscle firing patterns, or create tightness issues which then create asymmetry in the saddle, particularly with fatigue.
In very simple terms, we have muscles that are connected by fascial tissue in a helix or spiral pattern around our body, which are engaged for rotational movement. Our obliques, or muscles on the sides of our abdomen and back are important players. The problem for most riders isn't having axial movement, it's having it when and how you want it, and otherwise being able to resist it to maintain straightness while remaining soft and able to absorb movement in your torso. Flexibility AND strength in the sides and obliques in particular is very important for both hip and shoulder placement.
Analysis
My young client Kerry shows an example of axial rotation. She has had a tendency for her right shoulder to drop down and back. Her left hip also falls back somewhat. When she starts her ride she is much straighter. These photos were taken about half an hour into her ride when she was beginning to fatigue--which happened to be about the same time she was ready to work on more advanced work such as her pirouettes. Not a good combination.
