# International Survey Exploring Rider-Perceived Sidedness of the Horse

## TL;DR

An international survey found that many horse riders observe natural asymmetries in horses, which can affect their movement and training.

## Contribution

This study provides empirical evidence of rider-perceived sidedness in horses through a large-scale international survey.

## Key findings

- Horses were more likely to have upright right front hooves and prominent left shoulders.
- Movements like bending and lunging were reported as more difficult on the right rein.
- Many horses were perceived as mostly symmetrical despite observed asymmetries.

## Abstract

Equestrians often perceive horses to show a preference for one side of their body over the other, which can affect their movement and behaviour during training. To explore this, an international survey was conducted with over 2300 horse riders and owners, focusing on their observations of their horses’ movements and sidedness. Respondents reported that horses more frequently had their manes falling to the right, their right front hooves were more upright, and their left shoulders were more prominent. Horses were reported to struggle more with movements and exercises, such as bending or lunging, on the right rein. Many horses were reported to move their hindquarters to the left when walking, trotting, or cantering to the left. While clear patterns of left or right preference were noted, a substantial number of horses were perceived as mostly symmetrical. These findings support that horses have natural asymmetries, but the underlying reasons remain unclear. Understanding these tendencies can help horse owners and trainers develop more balanced training techniques, for the benefit of horse welfare and performance.

Laterality or sidedness in the horse is commonly addressed as part of the horse’s training. An international online survey regarding horse and rider sidedness and asymmetry was conducted, with 2304 useable responses. Confidence intervals (95%) were used to evaluate if some response options were chosen more frequently. Discounting answers of ‘not sure’ or ‘not applicable’, the right fore hoof was more often perceived to be more upright (22%) than the left (15%), and the left shoulder was more prominent (24%) more often than the right (17%), whilst most respondents reported no difference. Both lunging and bending was perceived to be most difficult to the right (48% and 52%) than to the left (33% and 42%), and more horses fell in on the right circle (lunging 40%, riding 38%) than on the left (31% and 33%). Horses commonly tracked their hindquarters to the left in walk, trot and left canter. Correspondence analysis showed that responses indicating horse side bias and relative symmetry, respectively, were associated across several questions, suggesting consistent individual patterns. While the mechanisms underpinning sidedness remain unclear, this study provides insights into horse owners’ perceptions of laterality and related matters.