The back of the Seatbones
Posted by Irina Yastrebova on Monday, January 30, 2017 03:10 PM
Lets look at the anatomy of pelvis, particularly side view - click here. In this picture the pelvis is very slightly tilted backwards which is exactly how it will be sitting in a dressage saddle. Notice that the very bottom point of the pelvis is rather closer to the back than to the centre. Notice also how round the bottom of the pelvis is which makes it pretty unstable and movable back and forth. It is very easy to allow the pelvis to slightly tip forward which puts the rider's seat on the front of the seatbones and pubic arches. The difference between these two positions in terms of angles and exact weight distribution is marginal. However, a rider with pelvis slightly tipped forward and sitting more on the front will be felt very different by a horse compare to a rider with pelvis slightly tipped backwards (provided the latter use core muscles to support that position and not glutes). Here are major differences:
  • Tipped forward pelvis will have an inclination to move backwards increasing the tipping even more. Usually, tipped forward pelvis goes hand in hand with tight lower back that holds the tipped position. This is especially common in young females with jumper/hunter background. It is very hard for the rider with tight lower back and tipped pelvis to match horse's movement . The rider must use upper body to create a "feel" of following the horse. If you watch jumper riders ride the walk their shoulders tip back and forth but their seat swings backwards and back to the center, it never swings forward. And the backward motion of the seat appears to be more energetic, dominant. The return to neutral position appears quiet, subordinate movement. The rider is "driving" the horse backwards! It is even worse in canter. Such riders cannot sit into the canter motion. They can only ride in light seat or two point because this way pelvis is away from the horse's back and the horse's motion is absorbed through leg joints - ankles, knees and hips. Pelvis is simply hovers or supposed to hover above the saddle. Some jumper riders move pelvis even in the two point seat by arching their backs in the rhythm of the canter!
  • Slightly tipped backward pelvis with supple lower back and strong supple core muscles will be moving forward and returning back to the neutral position describing a sort of backward circle. See more on that in the blog Role of seatbones/pelvis. If the rider is not driving with the seat she/he will feel for a horse like a quiet, easy to carry load that matches his movement.
Now, going back to the seatbones. What I found out about mine is I can seat to the back of my right seatbone easily but not to the back of my left. I cannot really control my left seatbone movement and it slides from under me backwards tipping me forward and I end up sitting more on the pubic arch then seatbone. Interestingly, my left shoulder likes to fall forward. I wonder if it compensates to create a feel of "following" the horse's motion. I found it in many of my students. Also, when a seatbone slides backwards the upper body will be inclined to lose balance and fall forward. I also see how horses "exploit" this weakness in riders and push their haunches out instead of staying engaged. The inside seatbone that slides backwards during the turns basically "encourages" a horse to swing the back end outward. I also found that my left leg "jumps" in to compensate for the lack of balance on the left side. I have hard time keeping it long with deep knee. Instead of the seatbone my knee "tries" to follow the horse by describing backward circles and detaching itself from the saddle. If I try to keep it quiet I start gripping.
Pelvis, including seatbones, is a solid bone. It's attachment to the spine at sacroiliac joint has very limited movement. Legs attach to pelvis through hip joints. The asymmetry that I described above can have several origins:
1. My pelvis is twisted from birth or accident;
2. I sit crooked and my pelvis is not centered and level over the horse's back (most likely scenario);
3. I can sit straight at halt but during movement balance unevenly on the left and right side.
A rider can have one, two or all three possible reasons for unbalanced seat. The factors that contribute to unbalanced position are several including uneven tightness in the muscles of hip joints, lower back and core (muscles that attach to pelvis). I have tighter adductors and hamstrings but longer/weaker hip flexors and obliques on the left side. This is my hypothesis - that tight hamstrings and adductors make my left seatbone less movable pinning it downward, long/weak hip flexors and obliques cannot lift pelvis enough to oppose the downward tendency. Because the left seatbone does not match the horse's movement it ends up being left behind the movement and slides backwards from under me tipping my pelvis forward. In order for me to match horse's movement I must sit on the back of my seatbones and make sure that my seatbones move forward toward my hands on the line I intend to ride at ALL TIME.
There are several prerequisites in order to develop a seat that horses like:
  • In order to be able to sit on the back of the seatbone through the full cycle of a horse's motion a rider must have very supple lower back. Lack of the suppleness will stop the movement of the seatbone at some point and can create in a horse a desire to drop the back, slow down, stop or twist the hips.
  • Strong and symmetrical core will assist the pelvis through the full motion of the horse's back
  • Supple hip joints will allow the pelvis and thigh bones move as horse's back requires them without unnecessary stiffness or lack of control
  • Learning exact biomechanics of seat movement in order to match horse's movement in all gaits. Role of seatbones/pelvis. Gaits
One of the most important advice I can give to all riders is to take time to observe instead of judge and jump to conclusions - observe yourself and your horse in all aspects including balance, movement, reactions, attitude, emotions, etc. It took me a long time to decipher where exactly my problem is. It was a journey and still is at peeling off layer after layer of compensations in my hands, shoulders, feet, legs, reactions to changes in balance or position. I have learned so much on that journey and I am looking forward to more discoveries in the future!
Happy riding...
Comment by Sabine oberhofer on Monday, May 15, 2017 08:16 AM
Thank you for your detailed observations! They really help me on my journey as a new rider.
Comment by Irina Yastrebova on Monday, May 15, 2017 05:51 PM
You are very welcome, Sabine. I am glad you found it helpful! :)
Comment by Dana Gastaldo on Wednesday, November 29, 2017 10:01 PM
Hi Irina, Thank you for all your investigated work about your self discovery journey. I have so many of the same issues and like reading about how you worked with your imbalances. Your words are so relatable to me. Thanks for sharing and helping me, Dana
Comment by Irina Yastrebova on Thursday, November 30, 2017 04:41 PM
Thank you very much, Dana, for sharing how helpful my blog was for you. I am always thrilled to hear that from the readers. It also encourages me to work harder :)
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