The leg is backup for the seat which we have talked about before, and is used quietly, without pinching the horse’s sides. The rider should be able to ride many times around the arena with the legs off, balancing on the elbows and very lightly on the feet. When the rider wants to ask a question or make a movement, then the leg is positioned and quietly applied, the seat remains steady and the contact soft but constant.
To understand your horse’s responses to your legs, it helps to understand negative reinforcement- removing something the horse does not like e.g. pressure.
You teach your horse that pressure means motivation, and release is the reward. Light aids come first and stronger one come quickly after so that the horse learns that a stronger pressure aid follows a light one if there is no response. A common mistake is to fail to release the pressure when the horse responds, which makes the horse dull to the leg aid and he feels lazy. We then say that the horse is “behind the leg”. We need therefore to tune our horses to a light aid. Positioning the horse deeper or higher through the neck and forehand also affects the answer we get from our light leg aid.
The leg can influence various parts of the horse’s body, not only the hind quarters. They need to be used on different places on the horse’s sides and ribcage, to stimulate the muscles. Learning to use these variety of ‘feels’, encourages the horse to lift his abdominal muscles, so that he appears to draw himself upward which makes him look taller with longer legs.