A study on the techniques used by untrained horses during loose jumping

Deterministic models' developed for the jumping horse indicated the importa nt factors involved when jumping an obstacle.(2) SVHS video recordings were obtained of 31 untrained horses (age: 3-5 years, height: 164.7 +/- 4.5 cm) jumping loose over a fence 1 m high by 0.5 m wide. The horses were designa ted to either a good group or a poor group based on a qualitative evaluatio n; good horses (n = 18) cleared the fence with ease, and poor horses (n = 1 3) consistently hit the fence. Video sequences were digitized to provide ki nematic data on the horses' center of gravity (CG) and carpal and tarsal an gles. Twenty kinematic variables were examined from the approach to the lan ding. Analysis of Variance (ANOVA) revealed significant between-group diffe rences for the horizontal velocity of the last approach stride (Good: 5.77 +/- 0.80 m.s(-1); Poor: 6.42 +/- 0.95 m.s(-1) p = 0.046). Significant diffe rences were found in the relative carpal angles at take off (Leading limb: Good: 1.02 +/- 0.19 rad, Poor: 1.25 +/- .0.28 rad; p = 0.010; Trailing limb : Good: 0.92 +/- 0.21 rad, Poor: 1.06 +/- 0.15 rad; p = 0.046). The height of the CG over the center of the fence was also a significant variable that differed between the groups (Good: 1.83 +/- 0.08 m; Poor: 1.71 +/- 0.13 m; p = 0.002). Finally the horizontal velocity of the landing was significant (Good: 5.26 +/- 0.92 m.s(-1); Poor: 6.27 +/- 0.84 m.s(-1); p = 0.004) alon g with the angle of the CG to the ground at landing (Good: -0.45 +/- 0.08 r ad; Poor: -0.38 +/- 0.07 rad). The velocity and CG variables which distingu ished good and poor horses are likely to be strongly influenced by a rider; therefore, it is unlikely that these data alone could be used to predict e lite jumping horses. The carpal angle data, however, may indicate a certain natural tendency by the young horses in the good group to keep their legs clear of the fence.