Gait analysis via computerkinematography

With the newly developed method of computerkinematography we analysed more than 300 jumps of 5 horses across obstacles of heights between 1,00 and 1.6 0 m. The accelerations were measured at the metapodia. In the run-up, the u sual frequency of the gallop was increased. In the last cycle before take-o ff the hindlimbs often touched down before the liftoff of the forelimbs, so that the suspension phase disappeared. The take-off seems to be a bipedal phase, but in fact the trailing limb touched down shortly before the leadin g limb, and its acceleration was higher. There was marked individual variat ion, in particular in the less thouroughly trained horses. Maximum accelera tions were found at the hindlimbs, especially during touchdown before the t ake-off, and in the touchdown after the landing. Surprisingly, the accelera tions of the forelimbs were lower in nearly all cases. The highest forelimb accelerations occured during the landing and in the following cycle. The l atter was very short and fused to the former without time interval for a su spension phase. The temporal succession of the limbs determined the lead of the gallop after the landing. Three of the horses under investigation land ed always on their left limbs, with the right limbs leading. When going cou nter-clockwise they corrected their gallop after three or four cycles. We f ound clear differences between jumping under the rider and free jumping, th e controlling influence of the rider could thus be proved. The relation bet ween the measured acceleration and the loads (that is, the ground-hoof-forc es) is discussed.