Symmetry implies that both forelimbs and both hind limbs are used equivalently. A sound horse moving in a straight line and on a flat surface should have symmetrical movements. Indeed, he should apply the same weight to the left and right forelimb, and the same goes for the hind limbs.
Seaver measures the symmetry of your horse at the trot and in a straight line, in order to compare the two half-trot strides. They should be as similar as possible.
This datum is calculated every 5 seconds of straight line consecutive trotting, and is represented by a grade in % that evolves during the session. For a sound horse, the score is usually between 80 and 100%.
Figure1: Classic training session with distribution of notes throughout the session
It should be mentioned that calculations are made only when your horse is trotting for at least 5 seconds in a straight line. In other cases, this grade has no meaning and will have a value of 0 on the graph.
For example, when working in a small space (as is the case for the graph below, 20x30m indoor riding arena), this duration can only be reached on a perfectly straight diagonal. So do not worry if no score is obtained during this kind of session. It is the same for a lunging session or liberty training where it is rare to put the horse on a straight line long enough, even when changing circles.
Figure 2: Trot symmetry when working in a small space
You will also find, for each training session performed, an average grade (in %) corresponding to the symmetry on each of your horse’s diagonal pairs of legs. The ideal horse has a 50-50 distribution on each side, and thus has a symmetry grade of 100%.
We also give you the average duration in milliseconds of each of the half-strides; it allows a more precise comparison between the two diagonal pairs. The length of the right half-stride corresponds to the elapsed time between the moments the right diagonal pair (right foreleg and left hind leg) and then the left diagonal pair hit the ground.
Ideally, symmetry should increase throughout the session (horses are often less at ease at the beginning of the warm-up), and with training; the better trained the horse will be, the better he will be able to counterbalance his natural dissymmetry.
The symmetry figures will allow you to check if you horse moves symmetrically, and see the evolution of symmetry as you work and from one session to another.
In case of sudden decrease of symmetry over several sessions, it might be interesting to ask a professional (coach, vet, osteopath) for their opinion.
Please note that lateral work and outdoor training on deep or hard grounds can alter the symmetry grade.
The major benefit of the "symmetry" feature for any rider is to be able to detect a weakness or lameness before it is visible, and therefore act to prevent the problem from getting worse and allow for a faster recovery.
Indeed, the diagonal pair with the lowest percentage of the two is the one that spent the least time touching the ground. It is thus the ‘weak’ diagonal, on which the horse bears the least weight. Below 40%, it is likely that the horse is suffering from lameness.
It is useful to monitor the evolution of symmetry within the same session thanks to the graph. In addition, with the average you will be able to see this evolution for the different training sessions performed. The grade itself is of little importance, except to monitor the evolution, unless it falls below 40% in which case a lameness will likely to appear.
See you soon for a new article on a Seaver feature!
The Seaver team 🙂