Components of the total kinetic moment in jumping horses.

The research article focuses on understanding the kinetic moment in jumping horses, specifically identifying the significant contributors among the body segments during different phases of a jump.

Methodology

The study involved observing and recording the jumping of thirty horses, using a panning camera that operates at 50 frames per second. The horses jumped over a fence that was 1.20 x 1.20 m in size.

• The researchers placed markers on nine joints of the horse and seven joints of the rider. This was done to track their movement in 2D using the TrackEye system, a specialized software designed for motion capture and analysis.
• They used a geometric algorithm to calculate the center of gravity for each segment. The moment of inertia, on the other hand, was determined using a cylindrical model.
• Data was then filtered and resampled to acquire the kinetic moment for each part of the horse’s body.

Findings

The study aimed to evaluate the relative roles of each body segment to the horse’s overall rotation during each phase of the jump – take-off, airborne, and landing.

• It was observed that the trunk, hindlimbs, and the head-neck sections had the most influence.
• Coordination between the body parts allowed the horse to maintain control over its angular speed of rotation while jumping over the fence. The researchers found that this speed stayed nearly constant during the airborne phase, at about 120 +/- 5 degrees per second.
• The kinetic moment was also stable during the airborne phase of the jump. This was because its value was equal to the moment of the external forces, which were approximately 722 +/- 125 kg x m2/s.
• The utility of this research lies in its potential to inform training routines and performance optimization for sport horses, while also contributing valuable insights to animal biomechanics.