When it comes to riding, having a strong seat is vital. Anyone that rides will tell you that riding a horse uses muscles that you don’t use for anything else. Regardless of your discipline, sitting astride an unpredictable animal is hard on the body & strong muscles will help to keep you balanced should when the unexpected happens.
The video below is short and offers easy exercises that you can do while mounted (at a standstill or a walk) and they all emphasize keeping your seat deep and developing essential riding muscles. They are simple exercises and while they may look a little silly, they are meant to develop muscle in the lower body, thighs and bottom.
For those of you who diet and/or torture yourself at the gym these exercises will help keep the body shapely (and strong) by targeted those pesky problem areas.