Are kinematics of the walk related to the locomotion of a warmblood horse at the trot?

In purchase examinations or at studbook selection sales the locomotor apparatus of horses is judged both at walk and trot. To evaluate whether kinematics of the walk are related to the locomotion at the trot, fore and hind limb movements of a group of 24 26-month-old warmbloods were recorded at walk and trot on a treadmill (1.6 and 4 m/s) using a modified CODA-3 gait analysis system. The intralimb coordination patterns at walk and trot were compared, and temporal and spatial variables of these gaits were related. Stride and stance durations (s) were shorter at the trot, while the stance distance (m) and swing duration (s) remained the same. Moreover, the pattern of the joint angle-time curves at walk and trot looked rather similar, though shifted to the left at trot because of the shorter relative stance duration. During the stance phase, the shoulder, stifle and tarsal joints were more flexed throughout, while the carpal and fetlock joints were more maximally extended in the trot than in the walk. In the swing phase, the elbow, carpal, stifle, and tarsal joints were more flexed because of the higher 'operating' speed at the trot compared to the walk. All other kinematic variables at the trot could be predicted from the mean +/- lsd of the values recorded at the walk. Moreover, nearly all kinematic variables at the walk correlated well with those at the trot, while variables indicating gait quality of the walk were similar to the ones identified previously for the trot. In conclusion, kinematics recorded at the walk in a group of horses were similar to and thus predictive for locomotion at the trot providing the decreased stance duration and the increased speed of the trot are taken into consideration.