A descriptive study on three Icelandic horses measuring differences in vertical asymmetry during trot in a straight line and in a circle between two saddle placements using an objective gait analysis system

Abstract

In Iceland, saddles are typically placed more caudally on the horse’s back than what is traditionally taught in other disciplines. It is believed to enhance shoulder freedom and overall gait performance, but there is very limited scientific evidence that supports this belief. This study aimed to explore if and how two different saddle positions affect symmetry in trot in three Icelandic horses, using an IMU-based objective gait analysis system (Equi-Pro). Three conditions were used to assess the horses: in-hand without a rider, ridden in a traditional saddle position (P1), and ridden in a more caudal position which is commonly seen in Icelandic horses (P2). Objective data on vertical movement asymmetry (minDiff and maxDiff values) was collected and measured at the head, withers, and sacrum. Additionally, subjective feedback from the rider on the perceived balance, comfort, and overall rideability of the horses was gathered to complement the objective data. Overall, the objective data indicated better symmetry in P1 compared to P2, although the differences between the positions were generally small and varied between the horses. The rider consistently favored P1, reporting better balance, responsiveness, and overall comfort, while noting increased tension, shorter strides, and balance issues in P2. Individual variations between horses, familiarity with P1, and other factors such as differences in training, a shift in saddle position, and measurement delays may have influenced the results. This study suggests that saddle position might affect both symmetry and rideability, although the effects are highly individual. Further research is needed involving larger sample sizes, adaptation periods for saddle positions, repeated measurements, and assessments of physiological stress responses to gain a better understanding of the potential biomechanical and behavioral effects of saddle placement in Icelandic horses.