By: Larissa Cox
The Longtissimus Dorsi, the longest muscle of the horse, runs over the top of the back, basically running from the croup to the withers. The rectus abdominus is the underside of the belly. Muscles work in opposing pairs, also called antagonistic pairs. The extensor muscle opens up, while the flexor muscle closes. On a horse, if you think of the horse going round as it being a “bow” shape, the muscle on top is in extension and the muscle on the bottom is in flexion. In order to help build up the horse’s ability to “go round”, really, what you need to do, is help the flexor muscle flex, which is help the abs crunch – abs underneath the belly of the horse. It was shown in by Roberts et al (1998) that this happens in trot rather than walk.
If you look at the skeleton above, you see that the vertebrae of the neck are actually pretty far down in the neck. Therefore, it takes a lot in order to lift these vertebrae up and create that extension and opening up of the joints. Basically, you need to lift the whither up, while maximizing that extension over the rest of the topline (longtissimus dorsi, LD) and flexion in the abs.
This might be hard to do when riding because there is always the weight of the rider sitting on top of the extension muscles. (Affirmed by De cocq et.al.2006 - weight of the rider puts horse’s back into flexion. Therefore, one needs to maximize extension - round over the topline on the ground first before adding the weight of the rider). There are several ground exercises that you can do to facilitate improved way of going. Basically, what you are doing is improving the horse’s proprioception (an awareness of where one’s body is in space) by feeding the horse sensory data while moving, therefore impacting the movement pattern.
So, what you want to do is connect the back end of the horse to the front end of the horse at the trot – to stimulate the abs to flex and the LD to extend. It has been said that the Pessoa lunging system is one of the smartest investments a rider could make, because it does just what you want – work the horse connecting back to front. The Pessoa system does not, however, work as a complete loop, but rather the two ends fasten separately to the roller so the aid is in fact a U shape.
The Equi-Ami system is the only training aid that functions as a complete loop which is acknowledged by a full UK patent. The Equi-Ami system is excellent for helping with ewe necks and rehabilitated thoroughbreds. The free movement in the continuous loop brings about increased softness and swing in a horse’s work and leaning and tension are avoided.
Once you have started working the horse “head-to-tail” on the ground, it’s time to start working the horse using the same methods while riding. Remember, to focus on driving the horse forward from behind and concentrating on lifting the withers up to create maximal flexion over the topline. Also, when training for this development, keep in mind, these “bow and string” muscles are engaged and utilized in the trot, and not in the walk. So, keep the tempo up while training for topline development, and relax and stretch in the walk.