We inherently know that a horse can only carry so much weight. Duh! Any living creature can only carry so much weight before succumbing to the burden. If you ask most people who know at least a little bit about horses, the general consensus is that a horse can comfortably carry 15-20% of its body weight.

Here are two short articles about two different studies. The first strongly supports the 15-20% range; the second supports a slightly higher number.

I’m not convinced that either study fully appreciated the number of variables that come into play.

• Horses are not designed well to carry weight to start with
• That weight over time (short term time and long term time) is going to have an effect
• That beyond the ability of the rider to balance with the horse, that the skill, or lack of skill, of the rider to increase the horse’s engagement consistently is a huge factor for weight carrying ability
• That general conditioning of the horse is going to affect a horse’s ability to carry weight, and last but not least,
• That the horse’s conformation plays a huge role as we’ve begun to discover after analyzing the toplines of our six candidate horses, and might also general constitution; will, personality, temperament…play a role?

I loved the mention of loin width in the first article and how horses that possessed more loin broadness suffered less muscular strain.  Somebody in the study connected some of the dots.  And I loved the mention in the Japanese study of the effect an unbalanced rider has on a horse.

Overall I think these studies are really just tips of the iceberg studies. They reveal bits of valuable information, but don’t take enough parameters into consideration.  Giving some basic duh! results isn’t particularly helpful in further educating people. The lighter, fitter and more skilled a rider, and the better managed, conditioned and trained the horse is, the easier and more efficient it is for the horse to carry the rider. This leads to longevity more so than making sure one doesn’t exceed a certain percentage point of their horse’s body weight.   Having a guideline like we’re given in these studies is, I suppose a good thing, especially for people who don’t have common sense. Though, I’d venture to guess that most of those people wouldn’t bother with looking up or following a guideline, anyway, so what’s the point?

My #1 size guideline is that my horse’s butt be bigger than mine.