We have experimented with narrower seats and the results were disappointing. It is the spread of the legs, called hip abduction, that stabilizes the pelvis and allows the spine to rest in a natural posture. Hip abduction also insures your hip joints are in their ideal alignment in their sockets. As hip abduction decreases, the spine became less stable, the pelvis tilts backwards, and the hip joints move out of their resting position into a compressed state.

A saddle seat can only keep your back straight if your knees are spread wide. If your knees come together you will slump, no matter the shape of the saddle. The angle formed by your thighs and torso should be about 135 degrees. If you sit lower than that, it will be difficult to get your legs into the proper straddle position.

Some saddles are wider than others. If the saddle is narrow it must provide additional support for the pelvis. This is usually done with sacral support, for example, a cantle or rise in the rear of the seat. While this can help keep the pelvis upright, but can create saddle fitting problems. For people with more ample buttocks, a sacral support often pushes the body forward in the seat and creates pressures on the genital anatomy toward the front.

Be sure your clothing does not interfere with your hip abduction (leg spread). Wear loose trousers or a wide skirt.