Rollkur is a controversial training technique in horse riding where the rider uses the reins to force the horse’s neck into an extreme downward curve, pulling the chin toward the chest. The horse’s face ends up well behind the vertical plane, and in the most extreme cases, the chin can touch the chest. The practice has sparked intense debate in the equestrian world for decades, with a growing body of research documenting its effects on the horse’s airway, spine, stress levels, and ability to see.
How Rollkur Looks and Works
In normal riding, a well-trained horse carries its head with the face roughly vertical to the ground. In rollkur, the rider applies strong rein pressure to flex the horse’s neck downward and inward, pushing the face past vertical so it angles back toward the horse’s body. The degree of flexion varies. Some riders aim for a mild tuck behind vertical, while others force the neck into the most extreme curl physically possible.
The technique is also called “low, deep, and round” (LDR) or simply hyperflexion. The name “rollkur” was coined by German professor Heinz Meyer in 1992. It doesn’t refer to any anatomical structure; it simply became the term that stuck with the public. Proponents argue it increases suppleness and submission. Critics say it achieves compliance through discomfort.
Origins of the Controversy
Hyperflexion was reintroduced in modern riding by the Schockemöhle family in the 1960s for show jumping, where it was used without much public pushback. The real firestorm began when successful dressage trainers adopted it, because dressage is judged partly on the quality of the horse’s movement and self-carriage. Seeing elite horses ridden with their chins tucked to their chests struck many observers as contradicting the sport’s own ideals.
The Fédération Equestre Internationale (FEI), the global governing body of competitive dressage, held Round Table conferences on the topic in 2006 and 2010. Research comparing video from the 1992 Olympic Games and the 2008 World Cup Final found that elite dressage horses were consistently ridden with their heads behind the vertical in collected gaits at both events, suggesting the practice has been widespread at the top level for some time. FEI rules technically require horses to carry their faces at or near vertical, but enforcement has been inconsistent, and the controversy continues.
Airway Restriction
One of the clearest documented harms involves breathing. When a horse’s neck is curled into hyperflexion, the throat narrows. A radiographic study of 35 sport horses measured the pharyngeal diameter (the width of the airway at the back of the throat) in different head positions. In the flexed position, the average airway diameter dropped to about 28.5 millimeters, with one horse measuring as low as 7 millimeters. That smallest measurement occurred when the horse’s face was more than 10 degrees behind vertical.
A narrower airway means greater resistance to airflow. During exercise, when a horse needs maximum oxygen intake, this restriction can cause turbulence in the upper respiratory tract and potentially trigger dynamic airway collapse. A separate study of five horses confirmed that in the flexed position, the resistance to breathing in increased while airflow decreased. The researchers concluded that neck flexion causes upper airway obstruction.
Pressure on the Neck and Spine
The nuchal ligament is a thick band of elastic tissue that runs along the top of a horse’s neck, connecting the head to the trunk and playing a key role in balance. Hyperflexion stretches this ligament to its greatest length, and that stretch comes with consequences.
A cadaver study measured the pressure at two critical points along the upper cervical spine (the first and second vertebrae) during different neck positions. In hyperflexion, pressure at the site over the first vertebra reached 99 mmHg, more than four times the pressure recorded in a neutral position. Over the second vertebra, pressure hit 77 mmHg, more than double the neutral value. These pressure spikes were strongly correlated with the degree of neck flexion.
This matters because sustained or repeated pressure at these sites can lead to the formation of fluid-filled sacs called adventitious bursae, a condition known as nuchal bursitis. For horses already diagnosed with or at risk for this condition, hyperflexion is considered especially harmful. Even in healthy horses, the repeated strain on the nuchal ligament and surrounding structures raises concerns about long-term damage to tissues that are essential for the horse’s natural balance and movement.
Stress and Behavioral Signs
Horses ridden in hyperflexion show measurable signs of stress. A study comparing horses ridden in LDR (low, deep, and round) versus a lighter, more forward frame found that cortisol levels, the primary stress hormone, were significantly higher immediately after the LDR sessions. Heart rate and heart rate variability didn’t show clear differences between the two conditions, but the cortisol finding alone indicates that the experience is more physiologically stressful for the horse.
Beyond lab measurements, researchers have cataloged a range of physical effects during hyperflexion: high and irregular muscle activity in the large muscle connecting the head to the forelimb, disturbed blood flow in the neck (detected through thermal imaging), and increased prevalence of incorrect postures. Horses in this position also cannot see what is directly in front of them. With the face angled sharply downward and backward, their visual field shifts so they are essentially looking at the ground beneath them rather than ahead. For a prey animal that relies on forward vision to navigate its environment, this is a significant source of anxiety.
Why It Persists
Despite the evidence, rollkur remains in use because some highly successful trainers and competitors have built winning records with it. The argument from practitioners is that brief periods of deep flexion can increase a horse’s suppleness and throughness (the quality of energy flowing from the hindquarters through the body). Some distinguish between “aggressive” rollkur and gentler versions where the horse is encouraged rather than forced into the position.
The scientific literature, however, does not support a clear safe threshold. The physical effects, airway narrowing, ligament strain, spinal pressure, exist on a continuum that worsens with the degree of flexion. A systematic review and meta-analysis published in Scientific Reports documented negative effects across respiratory function, musculoskeletal health, and blood flow, with the severity scaling to how extreme the flexion was. The review’s findings align with the broader veterinary consensus that hyperflexion poses welfare risks that outweigh any claimed training benefits.
Several national equestrian federations and welfare organizations have issued position statements against the practice, and FEI stewards are now tasked with monitoring warm-up arenas for excessive hyperflexion at international competitions. Enforcement, though, remains a challenge. The line between “deep” and “too deep” is difficult to judge from the sidelines in real time, and penalties are rare.