Digging Deeper into Rider Asymmetry

David Kempsell is the co-founder and Managing Director of First Thought Equine Ltd, the company behind WOW Saddles, Flair, FreeSpace, Korrector, and Duskin Saddles.

He is also a qualified saddle fitter with The Society of Master Saddlers (SMS), bringing scientific precision, logical design expertise, and problem-solving skills to saddlery - all grounded in a lifelong passion for riding and upholding the highest standards of Ethical Equine Performance.

In the previous instalment we described a rider who consistently sits to the right.

This is the pattern we encounter most often, so we will continue using it as our example throughout this series.

To clarify: a rider who sits to the right usually does so because the right seat bone sits higher than the left. The most common reason is that the right leg is slightly longer; either structurally or functionally. The precise cause matters less than the effect: the rider’s centre of gravity shifts to the right.

The body responds instinctively. To keep the head centred over the point of balance, the rider subtly twists the spine away from its neutral position. This mild functional scoliosis then shows itself in the shoulders, with the shoulder on the side the rider sits towards appearing further back. In our example, that is the right shoulder.

It’s All in the Legs

As discussed previously, the longer right leg is often the dominant or “dynamic” leg.

Here is where the pattern becomes interesting.

Because the rider’s weight is falling to the right, they instinctively try to stabilise themselves by gripping with the left adductor muscles; the group of muscles on the inside of the thigh responsible for closing the legs together and helping stabilise the pelvis.

However, muscles rarely work in isolation. The brain controls movement through coordinated patterns rather than individual muscle actions. So when the rider grips with the left inner thigh to stay centred in the saddle, that action often draws the left heel upward and creates tension through the ankle and lower leg.

The rider then feels as though they never truly have their weight in the left stirrup.

What develops is a familiar static–dynamic pattern:

• The left leg becomes the static, stabilising leg

• The right leg becomes the dynamic, mobile leg

  
  

This mirrors the footballer’s stance: the left leg stabilises while the right leg kicks. In riding, the left leg supports the rider’s position while the right leg remains relaxed and free to apply aids.

The problem is that the left leg can only function effectively below the knee. If the rider relaxes the left thigh, their weight immediately slips to the right. So the left thigh must remain engaged just to keep the rider upright.

Over time this becomes completely normal to the rider. It is a deeply ingrained movement pattern used thousands of times a day. Like scratching one’s nose, it happens without conscious awareness.

What Have Legs Got to Do With It?

The key point is this: the pattern can be changed.

If the rider is given a slightly unlevel platform; one that supports the higher seat bone; the pelvis can be brought back to a neutral position. Once the pelvis is neutral, many of the compensatory patterns in the spine and legs begin to reduce.

To achieve this, support must be added under the higher seat bone. In our example, that is the right seat bone. By doing this, the pelvis is prevented from tipping right, and the rider no longer needs to twist or grip to stay balanced.

If the height difference between seat bones were, say, 3 mm, then adding 3 mm of support under the higher seat bone could allow the rider to sit with a neutral spine and pelvis without muscular compensation.

A useful comparison is leg-length discrepancy when standing. If one leg is shorter and the pelvis cannot fully compensate, a heel raise is prescribed for the shorter side. This restores balance.

When sitting in a saddle, however, the legs are not the primary balancing structures. Balance comes through the seat bones. It is almost as if you are standing on your seat bones rather than your feet.

So, if the seat bones are unlevel, the correction should be made at the seat, not at the stirrups.

An unlevel pelvis requires a seat-bone riser, not a heel riser.

By addressing the rider’s asymmetry at its point of contact with the saddle, we can begin to change the loading pattern on the horse; and that is where meaningful change starts to happen.

For a WOW saddle that's where Flair comes in.

A truly harmonious partnership begins with perfect balance and symmetry

WOW make the world’s only saddles with seatbone support and Flair™ air flocking, providing the ultimate saddle balance by correcting asymmetry in both horse and rider.