“At speed higher than the walk, the amplitude of the axial movements is reduced and difficult to discern with the naked eye. Presumably, the muscular resistance increases, making the vertebral column as nearly rigid as possible in order to resist wasteful sidewise, lateral motion.” (James R. Rooney, Biomechanics of Lameness in Horses, 1976)
More than 40 years ago, James Rooney aimed the equestrian world in the right direction, explaining that gaits and performances do not improve releasing, elongating, or stretching muscles as previously believed.
Muscles resist, redirect, and diffuse forces. There is a very large elastic-stiffness diversity across vertebrate muscles allowing the muscles to adjust their tone to the demand. Today’s knowledge is far greater, but the fundamental principle remains the same; the vertebral column is the axis upon which the limbs act to produce motion. Forces induced on the vertebral column by the limbs as well as gravity, inertia, and rider movements, are resisted, converted, and/or redirected by supple resistance of the back muscles.
“The musculature of the vertebral column, particularly the epaxial, resists or absorbs the sidewise forces in order to promote forward movement. This action is clearly apparent at the walk.
“For example, if RH (Right Hind) and LF (Left Front) are on the ground, RH will push on the axis to the left. If there were no resistance, the axis would bend in the position of the dotted line. Since there is resistance, the axis takes the position of the solid line (A). Left front, conversely, is pushing the axis to the right, and the dotted line again denotes the absence, and the solid line the presence, of resistance (B). Joining these two ‘resistance’ positions, we have a fair approximation of the actual position of the vertebral column (C).”
Since Rooney’s basic demonstration, the main evolution has been the understanding that most of the length changes required for performances and locomotion occurs, not in the muscle fibers themselves, but by elastic recoil of the associated tendons and muscles aponeurosis. (Payne et al)
Muscles also regulate the tension of fascia, which has a very large diversity of functions from increasing the power of the muscles to protecting the cartilages of the joints from excessive pressure. Tensegrity, integrity, elastic energy, force transport, are the new words of the equestrian art.
Monsieur de la Gueriniere taught about enhancing the art with the support of science. Today, science brings the equestrian art to a new level. Instead of just making the horse executing the move, we have the knowledge to efficiently prepare the horse for the move.
“Looking at life from a different perspective makes you realize that it’s not the deer that is crossing the road, rather it is the road that is crossing the forest.” (Muhammad Ali)
It is not the horse who resists a movement; it is the education that fails to prepare the horse for the move. Naturally, the horse executes the movement favouring his muscle imbalance or other issue. It is not the hocks that need to be injected. It is the dysfunction of the thoracolumbar spine inducing abnormal kinematics of the hind legs and consequent stress on the hocks that needs to be identified and corrected.
“Too often we forget that discipline really means to teach, not to punish. A disciple is a student, not a recipient of behavioral consequences.” (Dr. Dan Siegel, The Whole-Brain Child)
We have the knowledge to teach further, not to teach the horse to move away from the legs, which is submission, but to teach the horse how to coordinated the thoracolumbar spine in order to adduct one hind leg easily and soundly. Ease and effortlessness have nothing to do with stretching and relaxation. Ease and effortlessness are the outcome of sophisticated muscular work optimizing the storage and reuse of elastic energy in tendons, aponeurosis, fascia and muscles, as muscles can store elastic energy even with the absence of tendons. Fascial tissues are commonly used for dynamic energy storage during oscillatory movements such as at the walk, trot and canter.
“Supporting skeletal muscles contract more isometrically while the loaded fascial elements lengthen and shorten like elastic springs.” (Fukunaga et al. 2002)
The equine physique functions at a higher level of sophistication than it was believed when the equitation of gestures, the correct aids, was created. It is no longer about shooting words “the aids”, but instead, the conversation with the horse demands complete sentences. There is a concept of integrity that was hinted by the best riders, but was not emphasized in the classical literature. Frequency, for instance is part of the rider’s integrity. The rapidness of the rider’s adjustments needs to be tuned with the horse’s frequency. The rider might increase or decrease the tone of the back and abdominal muscles in the right measure but if the adjustment is executed faster than the horse’s frequency, the adjustment will likely trigger protective reflex contraction of the horse. The dialogue with the horse is about subtle nuances in muscle tone within an overall integrity.
Large hand movements as well as large leg movements as well as shifts of the rider’s weight are dropping the conversation with the horse to cues that the horse might distinguish in the middle of a chaos. Saslow measured the extreme tactile perception of the horse in the area under the rider’s legs.
“And, especially, we must respect their integration of exquisite tactile sensitivity with a muscle power that can override any of our commands if we neglect to make our request meaningful, consistent and polite.” (C.A. Saslow, Applied Animal Behavior Science) The scientist was surprised to find such very high tactile perception. The study was made in 2002 and no-one was aware of such exquisite tactile sensitivity before the study.
Even if the shifts of the rider’s weight and the obedience to the rider legs were part of the classical literature, the principles of riding, as well as the tools allowing subtle relations between the rider and the horse, need to be refined. Again, the principles of riding encouraging a forward shift of the rider’s weight, the “driving seat,” as well as the saddles encouraging such equitation downgrade the conversation between the horse and the rider to a series of gestures.
Anyone can ride at a high level of subtlety. In fact, both horses and riders are comfortable with an equitation based on subtle and harmonic nuances in muscle tone. The neutral balance is the foundation, A balance at the vertical of the seat bones without any back-to-front shift of the rider’s weight disturbing the coordination of the horse’s back muscles. The difficulty is not to do it; the difficulty is to rise above the equitation of gestures and shifts of the rider’s weight that is sold as classical. “Respect for tradition does not precludes the love of progress.” (Colonel Danloux)
The love of progress is the love of the horse; the ability to understand the underlying biomechanics factors give the horse the ability to perform at his full potential and remain sound.