i'll give it an honest try.
if your feet/stirrups are sitting below you with your weight in them bracing, a hard stop will use the force like a pendalum and push you forward up and out of the seat. if you're "sitting" by tucking your butt underneath yourself, you melt into the horse with the stop and are riding him thru it instead of getting in his way.
someone mentioned they couldn't trot a horse without standing in their stirrups. if you have a seat and post to the inside leg not only will you be much more comfortable and less tired end of a long day, when those wild ones get to spinning in 1/2 a second you'll still be seated.


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