on a horse, I have very good posture any other time not at all, like I am ALWAYS slouching, I find it extremly uncomfortable to sit up straight even for a few minuts, I also do Pilates regularly because we do them for dance, I did not even know it was supposed to help your posture, never made a difference for me people always complain about my posture though, but I am just the kind of person that goes for comfort over all lol