RIDER POSTURE
So how does all of this work anyway?  Well, think of this.  The horse mimics what you do.  If you ride with an arch in your back then so will your horse.  If you freeze the motion in your back then so will your horse.  For the chair seat, if you do not use your core then neither will your horse.  This is bad posture. To ride with good posture you must engage your core.  Sorry, but there are no free rides until you build your core strength to distribute your weight evenly to the three points of balance.  Once your core has learned to work with the movement of the horse, riding feels effortless.

Relaxed seat, chest up
Chairseat
How one sits on a horse directly affects the posture of the horse.  “Ole sway back” is a saying we all know as horse people.  I use to believe that a horse's back dropped because of old age.  Well, there is some truth in that, however, I have learned that if we ride our horses with good posture then the horse’s posture will stay good longer.  This means that their backs will not “sag” until they are closer to 30 or they will not “sag” at all. 

Riding with good posture means that you are carrying your own body weight over your feet. The stirrup should feel no different than the ground.  To understand this, stand on the ground.  Feel your body weight over your feet.  Check to see if you are standing with even weight in both feet and that your whole foot is touching the ground.  This means each toe to the heel.  Now try pushing your feet into the ground.  Impossible to do.  That is the feel you should have in the stirrup.  Your foot should shift weight (or rock) from the toe to the heel as the horse carries you along.  The pictures named relaxed seat chest up and down resemble best what I talk about here.  The rider’s body weight is balanced over the foot and seat.  These are the three points of balance.  From here the rider can easily ride.  The horse’s movement will swing her hips, and her core can maintain her balance. 
The lines drawn on the pictures are to better understand how the riders weight affects the horse.  The black line is a perpendicular line to the ground.  It runs from the middle of the riders shoulder to the ground.  This is the center of the body balance.  The red arrow shows where the weight of rider is being distributed to. The  blue arc line shows how the back  of the horse carries the weight of the rider.

The pictures labeled chair seat carry all of the rider’s weight in their seat.  The forward leg works as a lever or a brace for the rider.  In this position it is easy to put pressure into the stirrups.  In this position the leg of the rider can not communicate with the horse.  This leg drives the weight of the rider down onto the horses back.  It does not matter what type of saddle is used the weight distribution is still the same.

The heel down arched back is one that will be controversial because it is what we equitation riders take pride in.  I was one of those riders until I got tired of getting thrown off my horse, having lower back pain, knee pain, and ankle pain.  Unfortunately, the frozen position of equitation not only damages your body but it also damages your horses body.  The position forces the riders body weight into the front feet of the horse putting the horse onto the forehand. Navicular and front end lameness are common results of this position. 
Relaxed seat, chest down
Chair Seat
Heel down, arched back
Heel down arched back
Relaxed seat, chest up
To help my riders find proper balance over their feet I have them stand in their stirrups.  The foot of the rider will have to stay parallel to the ground or the rider will loose their balance.  Do not get discouraged if this takes you a while to get.  Most of my riders felt weak in their ankles when they tried this, myself included.  The stronger I made my ankles the easier it was to stand.  The key is to remember to distribute your body weight over the stirrup or the ball of your foot.  From here all you have to do is to bend your knees to sit in the saddle.  Now you are on the three points of balance.  If your leg moves either forward or back then you need to stand again to find balance over your feet.  Know that if your legs rotates to where your toes point out, as you sit, is not a bad thing.  As you develop as a rider you can change the angle of your leg so that the toe points more straight if that is what you want. 
Standing in the Stirrups
Horse
  Savvy
      Ranch

Cindy Schleuss, Owner
Photo by Julie Colt