Basis of Power
by Beth Valentine. DVM, PhD
So, what does all this mean to the horse owner? Well, when you connect the backbone and its associated muscles, tendons, ligaments, etc., to the legs of the rear limb and all their associated structures, you're looking at the primary basis of the horse's power. All these structures need to be properly formed and properly maintained for the horse to be able to engage the hind end and back to provide power, which is translated into pull through the collar and traces.
A horse with joint problems in either the backbone or the hind legs, or a horse that suffers from painful muscles, can't generate proper force. Tensing of the muscles of the back, as occurs during the trot and canter or while pulling weight, will be painful. The horse may appear resentful and may refuse to work. And, of course, if you ride the horse, the health of its back is critical, as the back carries the weight of the saddle and rider, which is much less evenly distributed than the weight of a harness.
There is some disagreement over whether a short-backed horse is a better pulling horse, as it may have fewer problems with its back over time, or whether a long-backed horse is a better pulling horse, as it can generate greater power. Long or short, the most important thing is that the horse have a healthy back.
The ability of the horse's back to bend from side to side is a measure of the horse's flexibility. Horses with stiff backs are often unable (or unwilling) to roll side to side. If you watch a horse rolling all the way over, you will see some remarkable flexing of the neck and back, with the head moving side to side so much that it can be hard to hold the end of a leadline unless you give it plenty of slack. This characteristic is likely the basis for the old saying that a horse that can roll side to side is worth more money than one that can't.
Bottom line: Leg problems resulting from joint, ligament, tendon, or muscle problems will put excessive stress on the horse's back. The same applies in the opposite directiona healthy back prevents undue stress on the leg joints, and makes the horse better balanced and more powerful.
PO Box 2067, Cedar Rapids IA 52406-2067
Phone: 319-362-3027 Fax: 319-362-3046
26 October 2011 last revision