Seven riders with their grand prix horses were observed on the treadmill. The horses were ridden in free trot with a loose rein, passage and three speeds of collected trot.
Markers on the rider’s upper body and pelvis collected information about the rider’s movements and position in relation to the horse.
In free trot with loose reins the rider’s pelvis was more cranially (anterior) rotated and the lumbar back more extended, the body inclined more forward. During higher speed collected trot and passage the rider’s pelvis is more caudally (posterior) rotated and the rider’s lumbar back is more flexed. In passage, it seemed that the rider uses his seat more actively.