Ryttarens rotation av bäcken och överliv vid ridning i trav
The aim of this study was to determine the basic movements of the riders? pelvis and upper body when riding in trot seated. The study was preformed at a treadmill with seven high level dressage horses and their riders. The movements of the horse and rider were captured with a motion analysis system (ProReflex®) and also recorded on video. The horses were ridden in collected trot, 3.0 m/s. An experienced dressage teacher evaluated the video recording of the horses and riders. The rotation of the saddles and riders are measured in three directions: rotation around the x-axis, (roll), rotation around the y-axis (pitch) and rotation around the z-axis (yaw).
The pelvis of the rider is lowered on the left side during the stance phase of the left diagonal and on the right side on the stance phase of the right diagonal. The rotation of the upper body was asymmetric in the stance phase of the left diagonal for three of the riders. The saddles pitching movement is in accordance with the trunk of the horse. When the withers of the horse are at the lowest position, the saddle is most rotated forward. When the withers are at the highest position at midstance, the saddle is rotated backwards at the most. The pelvis of the rider is rotated backward at the beginning of the stance phase. It rotates forward until the second half of the stance phase and then backwards until the beginning of stance phase of the next diagonal. The upper body of the rider rotates backward during the first half of the stance phase and forward during the second phase and the swing phase. The rider and the saddle rotate to the left during the stance phase of the left diagonal and to the right during the stance phase of the right. The average score for the seat of the riders were 6 when they were evaluated by a dressage teacher. The asymmetries that were seen in the measurements could not be detected on video.
The results indicate that the pitching of the rider is a passive movement with purpose to reduce the impact when the horse lands on the ground. Correlations were seen between the roll and yaw of the pelvis, when the pelvis was lowered on one side it was also drawn back on the same side. The evaluation of the video shows the importance of combining modern techniques with the skills of people with long experience of evaluation of riders and horses to get the best results of research.