The assessment of the effect of race training on the locomotory apparatus can be confounded by tissue responses to the increasing training load, such as dorsal metacarpal disease. The aim of this paper was to examine the changes in gait during the early stage of race training in a cohort of 19.2-year-old Thoroughbreds, 11 of which had previously been exposed to spontaneous pasture exercise and also to preconditioning exercise from an early age (CONDEX), and the remainder had been exposed to only spontaneous pasture exercise (PASTEX). Data were collected 52, 60, 77, 109 and 176 days after the horses had entered the racing stable. At each examination, the horses were trotted in-hand on a hard asphalt surface, and kinematic data were collected. The horses trotted slowest on the first examination day, with a significantly longer and slower stride and associated percentage stance time. On day 77, the CONDEX horses trotted faster, had a longer stride length and achieved mid-stance earlier than the PASTEX horses. Across both groups, the introduction of galloping was associated with a significant reduction in stride duration (0.69 ± 0.01 vs. 0.66 ± 0.01 s, P = 0.001), stride length (2.49 ± 0.03 vs. 2.38 ± 0.02 m, P = 0.004) and stance duration (27.3 ± 1.0 vs. 32.0 ± 1.0%, P = 0.001). The changes in gait appeared to be associated with the introduction of galloping and the associated tolerance of the CONDEX group to the musculoskeletal loading.

Kinematic analysis has been used to understand performance in many sports, but few objective studies of equestrian technique have been published. The objective was to describe movements of the rider's torso and arms relative to movements of the horse's pelvis and shoulder and the position of the bit during trotting. Six experienced female riders rode the same dressage horse at a sitting trot, with rider and horse kinematics collected. The trot is a symmetrical gait, which implies kinematic symmetry between the first and the second halves of the gait. Three trials of a half stride, from left forelimb lift-off to right forelimb lift-off, were analysed for each subject. In all riders, trunk angle was maximal (backward tilt) in early stance, at which time the rider's hips were closest to and the rider's shoulders were furthest from the bit. Trunk angle was minimal (forward tilt) at the end of stance when the shoulders were closest to and the hips were furthest from the bit. Range of motion of the rider's hips and shoulders varied greatly between subjects. Movements of the rider's shoulder joint and elbow joint were synchronized with the trunk oscillations, so the distance from the rider's wrist to the horse's bit changed by only 15 ± 3 mm during the stride. It is concluded that the six experienced riders were able to accommodate the motion of the horse's body while maintaining a consistent contact with the bit by minimizing changes in the distance from the wrist to the bit.

In Standardbreds, the main aim of early training (begun during the growth period) is the mechanization of athletes leading to a particular gait called the ‘flying trot’. The present cross-sectional study was undertaken to investigate the biomechanical and physiological factors involved in this gait change, and aimed to analyse the effect of age on gait and energetic variables in a population of Standardbred horses under training. One hundred and forty-three horses aged from two to seven years were tested on a track at three speeds (8.5, 10 and 11.6 m s−1) with a gait-analysis system. Gait variables (temporal and linear variables, symmetry, regularity, two-beat rhythm, dorso-ventral, longitudinal and lateral activities) were compared between four age groups (two-, three-, four-, and five-year-olds and above). After a standardized exercise test, two energetic variables (V4 and V200) were also compared between these groups. Most variables were influenced by age/training status. The results indicated that, from young to mature racehorses, stride length and duration increase; and gait becomes more symmetric and more regular. We also observed a decrease in dorso-ventral, longitudinal and lateral activities, i.e. a decrease of thoracic displacements. These differences could be elucidated at slow speed and were still obvious at high speed. V4 and V200 also increased significantly with age/training status. All of these results indicate an improvement in co-ordination and a decrease in metabolic cost with increasing age/training status. Thus gait acquisition could be related to an improvement in trotting efficiency.