Developing a healthy nervous system teaches the horse to regulate his stress as intended per nature but in a domesticated environment. This is a key component of my training and is embeded in classical training through the use of appropriate exercises.
As we ask our horses to perform in demanding ways (carry weight, learn movements on demand, respond to cues and further performing at higher levels in unnatural set-ups for the horse), healthy breathing and true relaxation are foundamental to healthy and effective training.