Many factors account for human/equine communication. And, one may indeed wonder exactly which of all bodily processes support it. Any quest to understand the physiology of riding can't help but tune into the current world-wide sorting of how bodies function. Any research of human/equine correlations will add to a biology of movement, based not on one, but on two living organism that merge.
Study-horsemanship has contributed to this quest a thorough inspection of the horse's biomechanics. These and human/equine nerve transfers are explored in the context of history. Researched are the horse's major muscle tractions and their interaction with equine posture; functions of the hindquarters, which, perpetuating posture and locomotion alike, permit the horse to bear the rider, while moving with ease. Light is shed on the amalgamation of autonomous nervous system and core activities, their relation to jaw and tongue and more. For practical purposes the rider's communication via body and via reins is viewed independently.
Riding consists of structural aspects, addressed in elementary questions such as, "How do I get on the horse?", "How do I remain seated?" "How do I convince myself to let go?" and "How can I be in harmony with my horse." On the horse's side equally fundamental questions arise. It needs to find out how to carry the rider, get straight and understand him. These questions and more will, in theory and practice, be dealt with in the course of SomE studies.
Another type of equine stand-still, the levade further illustrates SomE's concept. It at once refutes the 20th century assumption that a middle hand exists in the horse's body and illustrates a study-horsemanship observation. Nerve correlations rule equitation to a greater degree than muscular or even structural considerations.
In the levade the horse's forehand rises, while the hindquarters bear and balance the weight. This classical figure requires the full command of all postural activities. In this advanced classical exercise clearly the forehand rises above the costal diaphragm, which proceeds forward from lumbar vertebra one to ribs nine and the sternum's rear end. It is supported by the hindquarters below. The rider's seat and legs direct the horse's hindquarters, his shoulders, arms and hands monitor the forequarters. The rider, however, with that part of his body, which directs the hindquarters, rests on the forehand.
As regards conformation and position no obvious correlation exists between rider and horse. The picture changes, when one considers the distribution of nerves, particularly in the skin. Human dermatomes display a curious osmosis with riding's functions. They suggest the conclusion that the effortlessness of riding may be the result of nerve signals skin to skin. One fact in particular speaks to this idea. Innervations of the human skin proceed directly from the central nervous system. They interact with the sensory-motor system and touch on core activities. These systems are at the root of movements, motions and locomotion in the human and the horse.
The very distribution of dermatomes provides pertinent information
(1) Human lumbar dermatome one proceeds from the uppermost lumbar region to the loins, and - right under the seat bones - fuses into sacral dermatomes two and three.
(2) These cover the rider's bottom and proceed down the inside of his legs to ankles and feet. Due to the shortening of the human spinal cord, corresponding sacral nerve sections are located mid-back in lumbar vertebra one.
(3) In the horse lumbar vertebra one structurally marks the separation of forehand and hindquarters. Sacral nerve sections two and three are found in the center of the sacral joint, which is located in the croup's highest point.
There exist, in other words, in the human skin nerve impulse circuits, which relate to structurally completely different yet, as concerns electrical frequency, corresponding nerve impulse circuits in the horse. These frequencies not only feed an incessant exchange between skin and core in each individual. They are exchanged between man and horse. The question remains, how exactly these exchanges take place.
The practical value of this information soon enough becomes obvious. In the classical seat the rider from center back (L1) tunes into the horse's locomotion. He balances on his seat bones (S2/3). He commands the horse's hindquarters with his loins (L1 to S2/3). He fine tunes the horse's locomotion between calves, toes and heels (S2/3 and L/5) and thus commands the full range of equine locomotion. And, - similar correlations exist between the riders upper body and the horse's forehand. What's more all of these correlation function in the upright and in the forward seat, independent of the rider's posture. Observation of other systems, such as trains in the myofascial web render similar results.
The rider's body language is easily understood in a study of human dermatomes and the horse's skeleton. The communication of his hand with the horse's jaw and tongue, however, is best understood in a study of the core.
