Analysis of the equine jumping technique by accelerometry.

The study investigates the correlation between a horse’s jumping technique and the dorsoventral acceleration (movement in the up-down direction) detected at the sternum. Using a specialty belt with an accelerometer, the research records locomotor data from eight different horses while they navigate a show jumping course with 14 obstacles.

Methodology

• An experimental show jumping course was set up with 14 obstacles of varying difficulty.
• Eight saddle horses displaying a range of jumping abilities participated in the experiment.
• An accelerometer belt was securely fastened to the thorax of each horse to monitor the dorsoventral acceleration occurring throughout the course.
• During each jump, 11 different locomotor parameters were recorded from the dorsoventral acceleration-time curves. These parameters included acceleration peaks, duration of the jumps and stride frequency.

Results

The research discovered that the type of obstacle significantly affected both the peak of hindlimb acceleration at the moment of take-off and the peak of acceleration at landing. Poor jumpers were identified by higher forelimb acceleration peaks at take-off, a higher ratio between forelimb and hindlimb acceleration peaks, and a lower stride frequency during the approach to a jump when compared to successful jumpers. Knocking over an obstacle was connected with a low hindlimb acceleration peak at take-off and a high ratio between forelimb and hindlimb acceleration peaks.

Wavelet Analysis

The wavelet analysis applied in the study allowed observation of the consistent changes in the frequency domain of the dorsoventral acceleration during the approach and take-off phases. Strikingly different patterns were shown on the time-frequency images generated by the wavelet analysis when a horse cleared a vertical obstacle compared to when it knocked one over. When a jump was successful, there was an instant increase in stride frequency towards the end of the approach phase and significant energy content in the middle frequency range at take-off.