Skipping Mechanoresponsiveness 18
Skipping Mechanoresponsiveness 18
Jean Luc Cornille
Living organisms, such as humans, as well as equines, are constructed from tiers of systems within a system within a system. “The existence of discrete network within discrete networks in bones, cartilages, tendons and ligaments optimizes their structural efficiency as well as energy absorption.” (Christopher S. Chen and Donald E. Ingber. Tensegrity and mechanoregulation: from skeleton to cytoskeleton, 1999)
Behind gaits and performances, a network of systems, creates the precision, ease, amplitude and elegance of the move. Edsger Dijkstra wondered, "Why has elegance found so little following?" The answer is because there is a science behind elegance. The beauty of a gaits and the elegance of a moves result from precise synchronization of all the systems. Unfortunately, as says Mr. de la Gueriniere, “It is easier to turn to false practice than to do what is correct.” (François Robichon de la Gueriniere Ecole de cavalerie, 1731) False practices concentrate on the gesture through artificial means, skipping the subtle synchronization of the underlying systems.
For instance, lightness on the bit can be achieved through artificial means without resulting from advanced control of the horse balance. The horse is light on the bit but heavy on the forelegs and while the rider thinks lightness, the bones of the front limbs receive excessive load developing micro cracks or micro fractures. We have explained in a previous article how micro cracks in the subchondral bone develop later into arthritis in the joint.
Classical literature describes the elegance of the forelegs movement as a move “coming from the shoulder” combining moderated elevation of the knee with amplitude of the forward motion of the limb. Without advanced scientific knowledge, our ancestors explained their intuitions and experience using metaphors. The problem with metaphors is that even if they are not wrong, they are not accurate either. They don’t provide much insights on how the horse does it. In the light of today knowledge, the amplitude and elegance of the forelegs movements results from a cycle of elastic strain energy stored in tendons, aponeurosis and muscles during the first half of the stride and reused during the second half and the swing. Maximizing storage and recoil of elastic strain energy is achieved regulating weight and forces loading the forelegs. It is through sound and subtle education of the back muscles that the load on the forelegs can be regulated and consequently the amplitude, soundness and elegance of the forelegs movement can be enhanced.
Conversely, when the education of the back muscles is incorrect and trainers try to improve front limbs movements acting on the legs, they not only disturb the fundamental principle of efficient locomotion; storage and reuse of elastic strain energy, but they also disrupt proper synchronization between flexion and extension of the joints and their inward rotation. Exactly like the bones composing the hock of the hind legs, the bones composing the knee of the forelegs execute a rotation medial to lateral and lateral to medial synchronized with the flexion and extension of the carpus. Inward rotation occurs in the other joints as well. Optimum synchronization is the essence of spring, amplitude and elegance of the forelegs movements. Instead, disrupted synchronization induces abnormal stress on the joints from the shoulder joint down to the fetlock and coffin joint. Many arthritis developments in the joints as well as tendons, ligaments and check ligaments injuries result from training techniques disrupting proper synchronization of the moving parts, such as touching the limbs with a stick.
Here is for instance how James Rooney describes the movements of the carpal bones at impact of the alighting front leg. “Mc3 rotates from medial to latera at impact and C3 and C4 separate, C3 sliding medially and C4 laterally.” These rotations allow maximum contact with the higher row of the carpal bones and therefore stable situation for impact. Exactly like for the hocks, frictions and consequent arthritis occur when the precise coordination between flexion and extension of the knee and inward rotations are disturbed. It is irresponsible to be touching the legs with any kind of pole or whip, trying to artificially create legs movements, that are in fact, the outcome of precise synchronization of the forces acting on the limbs. The front limbs react to the direction, intensity and frequency of the forces loading the front legs and it is through the mechanism controlling translocation of gravity, the muscular system of the thoracolumbar spine, that the beauty and amplitude and elegance of the front limbs can be enhanced. It is like a dynamics sculpture. The beauty of front limbs movements is the outcome of a sophisticated coordination of the vertebral column mechanism.
Breeding programs give birth to extraordinary movers with extravagant forelegs action. In 1995, Reiner Klimke predicted the venue of better horses but warned against the fact that riding and training techniques were not evolving in proportion. Klimke’s prediction is today’s reality. Extravagant movers throw their front legs in the show ring but with a totally disconnected back. The fault is more the riding than the breeding. An equitation updated to actual knowledge could create extravagant but functional athletes. Instead, and paraphrasing Leonardo da Vinci, when extravagance is supported by training techniques incapable of properly coordinating the muscular system of the thoracolumbar column, the result looks like a stack of nuts or a bundle of radishes.