How do you ride your trot? A rising trot has many purposes, including aesthetics and our own comfort at this bumpy gait. But none is more important than the protective effects a well-done rising trot can have on your horse’s biomechanical health. French biomechanics researchers have learned that force distribution changes dramatically when we sit and stand with the rhythm of the stride. Combined with proper saddle fit and structure, that can make a big difference in equine back health—for better, or for worse.
“The pressure exerted on the horse’s back is more localized over the front part of the saddle, the withers area, when the rider is in standing phase,” said Henry Chateau, DVM, PhD, of the National Veterinary School of Maisons Alfort Equine Biomechanics and Musculoskeletal Pathology department, and the INRA, the French national agricultural research institution.
“That sounds like bad pressure on the withers—but that’s where a good saddle comes in,” he said. “The role of the tree (and the pommel) is to distribute that pressure laterally.”
Chateau carried out sensor-based movement analysis on horse/saddle/rider interactions along with fellow researcher Pauline Martin, DVM, PhD, of the University of Lyon, the National Veterinary School of Maisons-Alfort, the IFSTTAR LBMC Laboratory of Biomechanics and Impact Mechanics in Bron, and CWD France-Sellerie saddlery, in Nontron.
“And let’s not forget that the point of the rising trot is to accompany the vertical movements of the horse’s center of gravity,” Chateau said. “You do have to consider the dynamics of this phenomenon and not just restrict yourself to an interpretation of what would happen on a static (nonmoving) object. When the rider correctly performs the movement, this allows a synchronization of the shifts of gravity of both bodies (horse and rider) in interaction.”
In their study, Chateau, Martin, and colleagues compared the effects of a single rider’s position at rising trot on pressure distribution, spine movements, stirrup forces, and locomotion as he rode three horses. To do so, they measured the horses’ back movements using inertial measurement units (IMUs) and the forces using pressure mats under the saddle and sensors in the stirrups.
They confirmed obvious pressure peaks in the stirrups during the standing phase, Chateau said. But they also found that the sitting phase has an important consequence on the horse: It not only increases pressure on the horse’s back, but it also reduces the back motion compared to the standing phase.
Does that mean standing is better? Not necessarily, said Chateau. What’s important seems to be to follow the horse’s rhythm.
“A lack of rhythm leads to a desynchronization of the trajectories of the centers of gravity of the horse and the rider,” he said. “If the phases are in opposition, the rising trot can even become harmful. Fortunately, the advice is fairly simple: To make the rising trot comfortable for the horse, make it comfortable for yourself! Then, of course, make reasonable decisions, like never putting an overweight rider or a novice rider on a horse that hasn’t had the chance to build up his back muscles yet.”
Warmup is equally important, he added. While many riders and instructors encourage a rising trot warmup to “free” the horse’s back, this isn’t always the best idea.
“The vertebral axis is very solicited in the trotting gait, with ample vertical movements of the center of gravity and strong muscular activity in the back, which act to oppose the vertical movement of the abdominal mass,” he said. “Our biomechanical studies have shown that on a ridden horse, the rider increases these solicitations. So if you’re talking about a horse that already has back pain, it’s better to first increase the warmup period at a walk, and then consider substituting the warmup trot with a light canter instead.”
Regardless of how we ride or warm up, a well-fitting saddle is critical, he said. Therefore, his research group has teamed up with biomechanics researchers in a saddlery to study what kinds of designs make the most scientifically sound saddle.
“We’ve just created a common laboratory, called CWD-VetLab, to associate practical research with an actual industry partner, under the theme ‘connected equitation,’ ” said Chateau. He said their work will help perfect the “ideal saddle” and offer solutions for modifying existing saddles according to how horses move, including saddle adjustments for horses already suffering from back pain.
The study, “Effects of the rider on the kinematics of the equine spine under the saddle during the trot using inertial measurement units: Methodological study and preliminary results,” was published in the Veterinary Journal.