Research update: Impacts of stirrup iron style

Krishona Martinson
University of Minnesota Extension

The stirrup iron has the potential to modify the forces experienced by a horse and rider during ridden exercise.

A range of stirrup designs are available, but previous research has not investigated if these modifications influence a rider’s position and interactions with the horse. A research team from Michigan State University recently set out to determine if novel flexible, flexible and rotatable, or traditional stirrups irons positively impacts the welfare and performance of the horse and rider.

Four riders rode using the three stirrup types. Hip, knee, and ankle angles, toe position, and force were measured at the highest and lowest point of the posting trot and canter.

No significant differences were seen between joint angles, toe position, or forces between the types of stirrups. At the highest point, average hip, knee, and ankle angles were 169 degrees, 151 degrees and 94 degrees, while the same joints averaged 139 degrees, 124 degrees and 93 degrees at the lowest point.

Interestingly, right toes rotated more laterally regardless of stirrup type. The average forces applied were greatest at the highest point of the posting trot and lowest during the canter.

The researchers concluded that stirrup style minimally impacted rider position or the forces experienced; however, forces differed by gait. Future studies regarding how a rider’s experience and joint pains may contribute to asymmetries are warranted.

For more information on this research, read the abstract in the Journal of Equine Veterinary Science.