Originally published on Substack
A 2019 study suggests posture may reflect not just training — but the life the horse has lived.
Most horse people think they know what poor welfare looks like. Lameness, weight loss, obvious distress. But what if welfare is also visible in something far quieter? The shape of the horse's body.
In 2019, a study published in PLOS ONE asked a simple question: could a horse's posture reflect its welfare state? Not behaviour, not performance, but posture.
The idea that posture reflects emotional state is not new. As early as 1872, Darwin described how animals express emotion not only through facial expression, but through the body. Posture, he argued, is a key channel of emotional communication. Across species, this has proven to be the case. Animals experiencing stress, conflict, or fear show consistent changes in how they hold and use their bodies.
In horses, this idea has been extended to welfare. Welfare is now understood as the horse's subjective experience of its situation — how it perceives what is happening to it. Importantly, this experience is not momentary. Repeated exposure to stressors such as discomfort, restriction, or adverse management can lead to long-term internal states, and over time these states may be expressed physically, including through consistent postural patterns.
Methods
To investigate this, researchers studied 85 riding school horses across 11 schools in France. These were not selected for breed or type, but were typical working horses in everyday conditions.
To measure posture objectively, they used a technique called geometric morphometrics, which allows shape to be analysed precisely rather than described subjectively. Small grey clay dots were placed on specific anatomical landmarks along one side of each horse's body — points corresponding to consistent skeletal locations, from the base of the tail through the spine, up the neck, and along the head. Each horse was then photographed from the side, and the images standardised so all horses faced the same direction.
From these photographs, the researchers mapped the outline of the topline — head to neck to withers to back to croup — and added additional points along this outline so that the shape of the curve could be captured in detail.
Findings
The patterns that emerged were consistent. Horses showing signs of compromised welfare — such as stereotypic behaviours like crib-biting and weaving, or "depressed-like" states — also showed measurable differences in body shape.
These horses tended to have flatter or more hollow necks, more open head–neck angles, flatter backs, and reduced curvature through the topline. The natural curves of the spine were diminished or lost. These changes did not appear in isolation but formed a whole-body pattern running from head to croup.
Importantly, these postural patterns were associated with independent indicators of welfare. Horses showing behavioural signs of compromised welfare were more likely to show these altered shapes. The researchers also distinguish these findings from acute pain. Acute pain tends to produce an exaggerated rounding of the back, whereas the horses in this study showed flatter, more hollowed profiles — patterns more consistent with chronic conditions such as long-term discomfort, stress, or management factors.
Discussion
This study shows that posture is not just a matter of conformation or training. Across a group of riding school horses, consistent differences in body shape were associated with independent indicators of welfare.
In practice, these postural changes are usually treated as training problems. A horse with a flat or hollow topline is said to need more topline, more lunging, more engagement. The assumption is that the body shape can be improved through the right exercises. This study does not dismiss training, but it does suggest posture may not be explained by training alone.
If posture reflects underlying state as well as physical use, then a hollow or flattened topline may not simply be something to correct. It may be something to understand.
Not every flat back is a training problem.
Some are the result of the life the horse has been living.
This study does not show that posture alone can diagnose welfare. A flat or hollow topline does not automatically mean a horse has poor welfare. But it does suggest something that is difficult to ignore: the horse's body may not just be something we shape, it may also be something that reflects the life the horse has been living.
Find the full article: https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0211852