The aim of the study was to compare the stability of the rider as well as the forces acting on a horse’s back with different seating positions at the trot (sitting trot, rising trot and two-point seat). The same experienced rider was mounted on 10 sound horses trotting on a treadmill. The kinetic data were recorded with an electronic pressure mat, placed under a well-fitting dressage saddle with no saddle pad. The rider used three different seating positions, each for 20 s. Right forelimb motion was used to synchronise the pressure data with the stride cycles. To determine the rider’s stability, the movement of the centre of pressure (COP) along the transverse (X) and longitudinal (Y) axes was calculated. The force was taken as the sum of all segments of the pressure pad multiplied by the area of the pressure pad. The maximum force and the X- and Y-deviations were evaluated using ANOVA for repeated measures with a Bonferroni Post hoc test. The stability of the rider in the Y-direction was significantly highest in the two-point seat, followed by the rising trot and the sitting trot, respectively. In the X-direction, there was no significant difference between the three positions. The significantly highest load on the horse’s back was at the sitting trot (2112 N), followed by the rising trot (2056 N) and the two-point seat (1688 N). The rider was most stable in the two-point seat while transferring the lowest load on the horse’s back. The rising trot was found to be more stable and less stressful for the horse’s back compared to the sitting trot.

The aim of the study was to compare the stability of the rider as well as the forces acting on the horse's back in the sitting trot and the rising trot. Ten sound horses were measured under the same experienced rider on a treadmill at trot. They were trained in 3 sessions to get used to the treadmill and were wearing a fitting dressage saddle without saddle pad. For collecting the kinetic data a pressure mat under the saddle was used. The rider performed the 2 different seating positions; sitting trot and rising trot 20 s each. Right forelimb motion was used to synchronise the pressure data with the stride cycles. For determination of the rider's stability, the movement of the centre of pressure (COP) along the transverse (x) and longitudinal (y) axis was calculated. To evaluate the load on the horse's back, the force was estimated. The force and the stability were evaluated using the ANOVA for repeated measures (p < 0.05) in SPSS 14.0. Significant differences could be shown between the seating positions for the maximum deviation along the y-axis. The stability of the rider in y-direction was significantly higher in the rising trot than in the sitting trot. In x-direction, there was no significant difference between the 2 positions. The amplitude of force was also significantly higher in sitting trot (1781 N) compared to rising trot (1476 N). The rising trot was found to be more stable and less stressful for the horseback when compared to the sitting trot.