Saddles that slide are not a pleasant thing to have when riding a horse. The horse is fine but the saddle slides forward when riding. It is a mystery to many riders and even the experts; Why does a saddle slide?
Why is it so bad that a saddle slides forward?
While the part on the front edge of a saddle or maybe even where the rider sits presses against the shoulder. This can cause the horse to take shorter strides due to pressure on the shoulders as it places the hoof earlier on the ground.
The question will become increasingly clear over time. Worst case scenario: The horse will no longer work from the hindquarters and starts pulling himself on the forequarters, or may even stumble. The first thing you would notice is the choppiness of the front end. Soon after, the shortening will pass all over this horse except for one area - back in the hindquarters.
Chair seat
Both the extreme height of the horse's shoulder and its wide configuration can also cause weight to be shifted further back along the front edge or longer rock saddle forward. Now the rider does not sit equally on the horse's back. The rear part of the saddle is carried further down, pushing the rider into a chair seat position. Some riders would try to compensate for this imbalance by leaning up in front of the seat and trying to create a new center of gravity. But as soon as the horse moves, it can slide back again and there you have another problem. This is when the seat becomes painful. The rider rocks back and forth, the horse must change its balance points with EVERY stride.
The seat compensation mostly happens subconsciously. If you talk to riders about how they feel in their saddle, most of them will say, "I'm falling forward."
Physical damage
If the increased rearward contact will provide inward force, the latissimus dorsi muscle plays a role behind the rearward motion of the front. The longissimus is a deeper muscle in the horse and serves to stretch through while enabling lateral bending. When immersed in more, this muscle will also be worn due to the greater weight of the rider. And a horse with an overextended spine (read - hollow back) cannot bend correctly, simply because of anatomy.
Now, when we ride forward again, the saddle sits on top of the ground rotating shoulder blades that keep moving in and out, meaning our saddle will inevitably slide from side to side. This throws the rider even more off balance, making it that much harder for the horse to find its own balance. Also, the pressure of your saddle on its shoulders will pinch skin nerves. The shoulder muscles, infraspinatus and trapezius will also exert excess effort.
In short: You cannot ride properly when your saddle slides forward. The horse will suffer physical damage. Therefore, a saddle must not be placed on the horse's shoulder blades.
Cause 1: The saddle was set too far forward
If the saddle was not placed behind the bow blade, the saddle will likely slide even more forward when the horse starts to move.
Solution: Just saddle the horse again and make sure the saddle is behind the bow blade.
If your saddle doesn't fit you, there are many ways it can cause back pain.
If the balance point is too far back where it needs to be right from the Get-Go, as soon as that horse moves you will slide back up onto the neck. When you ride in gears, the saddle moves forward inch by inch. If the saddle is too wide, it also slides forward. The chest is narrower than the horse's shoulders. The saddle will slide forward until it moves into a suitable space.
Solution
Costs would increase as a whole new saddle would have to be bought in. In other words, widen or narrow the saddle tree (or simply replace it with a different size esophagus) and change the amount of padding in panels. If the back of your saddle needs redressing; remember, don't make that stuffing too stiff. The saddle maker can help by adding a gusset panel or using a second piping to set the panels deeper.
Reason 2: The saddle does not fit
If the saddle's center of gravity is too far back from the start, it is likely that the saddle will slide forward again when the horse is in motion. During riding, the saddle will move forward inch by inch. It is also possible for a saddle to slide forward because it is too wide. The horse's shoulders are usually wider than the chest. The saddle slides forward to find its own suitable position.
Solution
The saddle will need to be refitted. This includes adjusting the saddle tree or rather the seat, or changing the padding in the panels. If the saddle needs to be stuffed in the back, make sure the stuffing is not too firm. The saddler can help by inserting a gusset panel or by setting the panel deeper with a second tube.
Cause 3: The rider pushes the saddle forward.
This is often due to many riders riding rising trots with too much lift and partly at the wrong time, lifting them further out of the saddles. This results in the saddle being pushed forward, i.e. directly on or even worse over to the horse's bow.
Solution
Hire a good riding instructor. If possible, you can also go back to outcome lessons. It may sound silly, but you have to learn your place. It's another reason why even professional riders learn lessons every day because it solves most problems for the seat being unbalanced from the rider.