Effect of added weight on landing kinematics in jumping horses.

Six event horses jumped a 1.10 m high table fence 4 times under each of 2 conditions; the rider weight condition involved carrying the weight of the rider and saddle (61 kg), whereas the added weight condition included an additional 18 kg weight cloth. Sagittal view, 60 Hz video recordings were analysed using standard methods. Comparisons between the rider weight and added weight conditions using paired t tests (P<0.05) showed a number of significant differences. In the added weight condition the leading forelimb landed closer to the fence, and there were increases in the maximal extension of the fetlock and carpal joints in this limb during the landing phase. In the first departure stride, the stance durations of both hindlimbs increased, and the advanced placement between them was reduced for the added weight condition. The head was significantly further ahead of the vertical in the added weight condition at the instants of ground contact of the TrH, LdH and TrF in the first departure stride.