Interestingly, the researcher said, they realized that each horse-rider couple seems to create a rather consistent saddle-asymmetry pattern that’s unique to that couple and is repeatable, trial after trial. | Photo: iStock

Researchers know that saddle slip could indicate poorly fitting tack or even a subtle hind-limb lameness. But that doesn’t mean a saddle shouldn’t move at all. Recent study results from researchers from Sweden suggest that it’s totally normal for saddles to shift left to right during the stride—as long as the movement is so slight it’s hard to actually see.

Sound upper-level dressage horses ridden at a rising trot on a treadmill experienced lateral saddle shifting of around 2 centimeters (5/8 inch) off the center, in particular when the rider was coming back down into the seat after rising. On a full-sized horse in motion, this shift would go mostly unnoticed to most observers using just the naked eye, said Agneta Egenvall, DVM, PhD, professor in veterinary epidemiology at the Swedish University of Agricultural Sciences Faculty of Veterinary Medicine and Animal Science, in Uppsala.

“Some saddle movement is normal,” Egenvall said. “But if increased beyond the normal range such that the saddle slips out of place, it could be worth considering both horse and rider asymmetries as possible causes