Desensitizing, groundwork, ground manners, lunging,grooming, liberty training, stretching,
Groundwork covers all sorts of exercises, including lunging, changing directions, backing, yielding quarters and hindquarters, leg yield on the ground, flexing... What's good about these exercises is that is really gets your horse responsive and respectful of you and your space as well as becoming more soft and supple. If your horse already knows these exercises, work on perfecting them.
Have you tried doing horse agility? There is a book on it