Transport cost determined from biomechanical variables estimated using inertia sensors in horses

Abstract

Determining the cost of transport (COT) through a conjunction between physiological and biomechanical assessment can be an exciting method for equine athletes' prescription and training load of Standardbred horses. The purpose of this project will be to quantify, with the aid of a wearable inertial measurement unit (IMU) for objective analysis of the gait, the heart rate and lactate cost of transport (COTHR) and (COT[La-]) to identify the level of conditioning of the ten Standardbred horses. Horses will be submitted to an incremental exercise test (IET) on a sand track. After a warm-up, the horses will perform three incremental phases, the last step being a sprint at an internal load close to the maximum heart rate. For the aerobic fitness of each horse, the lactate threshold (LT) will be determined by three different methodologies, visual method, V2 and V4 (speeds at which lactatemias reach 2 and 4 mM). Heart rate (HR), speed and distance exercised, and biomechanical variables, will be recorded using a movement analysis system (EquiMoves®, 200 Hz). In the standard setup, nine wireless inertial sensors will be used to measure the horse in all gaits. Limb-related parameters such as speed, the timing of footfalls, stride duration, number of strides, swing intensity, stance and swing duration per leg, protraction, retraction, abduction, and adduction will be determined. Component analysis (PCA) will be performed to detect the degree of co-relatedness among physiological and biomechanical variables and to differentiate each horse's degree of conditioning. (AU)