Usability of normal force distribution measurements to evaluate asymmetrical loading of the back of the horse and different rider positions on a standing horse.

Pressure measurement devices in equine sports have primarily focused on tack (saddle pads and saddle fitting methods). However, saddle pressure devices may also be useful in evaluating the interaction and distribution of normal forces between the horse and rider, including rider position and riding technique. This study examined the validity, reliability, repeatability and possibilities of using a saddle pressure device to evaluate rider position. All measurements were performed using a standing horse. Validity was tested by calculating the correlation coefficient between measured normal force and the weight of the rider. Repeatability was tested by calculating intra-class correlation coefficients. The use of normal force measurements to evaluate horse-rider interaction was tested by adding a known weight to saddle or rider and collecting measurements with the rider sitting in four different positions. The device was found to be valid and reliable for force measurements when the measurement device was not replaced. The system could be used to determine the expected differences with added weight and in different rider positions. The normal force distribution measurement device proved to be a valid and reliable tool for studying the interaction between a rider and a static horse provided it is positioned carefully and consistently relative to both the horse and the saddle.