All too frequently as vets on our rounds we are asked the question ‘Am I too big for my pony?’. A topic which has received a lot of scrutiny within the industry recently, highly inflammatory and difficult to bring into discussion without causing offence.
However, as owners and as vets we are responsible for the welfare of our horses and ponies we regularly see lameness or back pain, that may not exist if the animal had a lighter jockey. So in this article I will look at just some of the factors which contribute to the weight carrying capacity of our four legged friends.
Rider: Horse Weight Ratio
There has been a lot of publicity regarding rider:horse weight ratios of recent times, with many major county shows and societies using this to implement an objective measure of sensible rider weight in competition horses. It is currently accepted that the combination of rider and tack weight must not exceed 20% of the horse/pony’s weight.
Research on this continues but for now we know that horses who regularly carry weights that exceed 25-30% of their bodyweight experience increased muscle soreness and build up of lactic acid in the days post exercise.
With this method it is important to note that this ratio should be based on the horse’s ideal weight – just because your horse gains weight, doesn’t mean that you can too!
It is a common misconception that a taller horse can carry a heavier rider. This simply is not true – we need to subjectively assess how robust a horse’s conformation is and how this may influence it’s ability to carry weight:
“Bone” is the measurement of the circumference of the foreleg cannon bone,
just below the knee. One useful formula for determining if a horse can handle your weight is: Add the weight of the horse, rider, and tack together, divide this number by the cannon bone’s circumference, then divide that figure by 2; the result should be between 75 and 85.
When the number is higher than this, you are too heavy for the horse.
“Loin” is either side of the spine between the lower ribs and pelvis. Horses with short and broad loins are thought to have greater weight carrying capacity, however there is no research to support this.
This is why a 15hh cob is likely able to carry a greater weight than a 16hh thoroughbred will and why the term weight carry cob is derived.
The fitness level and balance of the rider is an important consideration when determining weight-bearing ability. A horse can more easily carry a well-balanced, agile rider than an unfit, uncoordinated person. Therefore, if you are a heavy rider, it is greatly to your advantage to work at staying as fit as possible.
Length of Work, Intensity and Frequency
Of course, it goes without saying that the length, intensity and frequency of ridden work will also determine the weight in which a horse can carry whilst carrying out the activity.
A gentle hack consisting of mostly walk work and in a straight line, is generally much less strenuous than jumping round a course of show jumps or performing an advanced medium dressage test.