The temporomandibular joint or TMJ is the most frequently used joint in the horse's body, explains leading equine dental surgeon, Dr. Katharina Ros. So when something goes wrong with the horse's teeth which causes it to chew its feed more with one side of its mouth, tension in the TMJ can spread to the entire body and nervous system of the horse. Learn how by watching this segment from Dr. Ros' equine dental hospital, Riedmühle near Frankfurt, Germany.

Rollkur has been a hot topic for years. Prolonged or excessive use of the technique is not allowed by the FEI. But how long is too long? EPONA.tv asked reigning dressage world champion Anky van Grunsven how she uses her controversial trademark training tool. Do bouts of hyperflexion of the neck last for 10 seconds, a couple of minutes or a quarter of an hour? "I don't have a clue," admits Anky van Grunsven. "Time flies when you're having fun". This interview was filmed at the 2008 Danish Warmblood Stallion Licensing.

Two hours of work in various degrees of hyperflexion and one blue tongue. Okay? Or too much? EPONA.tv asked Swedish Olympic rider Patrik Kittel whether he thinks he is riding in accordance with the FEI Code of Conduct.

In dressage, the concepts of rhythm, contact and outline seem abstract and hard to fathom or discuss to many fans and even to participants. But now these qualities can be objectively measured, using telemetric accelerometry and tensiometry. Here's how.

Can equestrian federations be trusted to police the welfare of performance horses? No, says Dr. Bidda Jones, chief scientist with RSPCA in Australia. If equestrian sport is to have a future, federations must show that the welfare of horses is really improving. Rule changes and independent welfare observers may be the way forward.

Science has long since shown that there is no such thing as a "naughty" horse or pony and that punishment increases the likelyhood of dangerous, fear induced behaviours like bolting and rearing and reduces learning too. So why are we still teaching kids to beat on ponies who don't live up to expectations? This footage was captured at two events in less than three days. Judge for yourself whether this treatment of show animals is acceptable.

This is part one of the 30 minutes of footage shown to Dr. McLean, Dr. Winther Christensen and Professor Ladewig. All footage was obtained using visible film equipment. The soundtrack to this footage has been muted to protect the privacy of bystanders.

This is part two of the 30 minutes of footage shown to Dr. McLean, Dr. Winther Christensen and Professor Ladewig. All footage was obtained using visible film equipment. The soundtrack to this footage has been muted to protect the privacy of bystanders.

Some equestrian sports are often labelled cruel, while others are accepted as humane as a matter of course. But according to Professor in ethology and animal welfare at the University of Copenhagen, Jan Ladewig, dressage horses may have a worse deal even than rodeo horses. Prolonged pressure and pain without any view to escape is far more damaging for a horse's pshyche than eight seconds of motivational conflict followed by release, feels this researcher.

Signs of fear and stress in horses are common at every level of equitation, according to Danish ethologist, Dr. Janne Winther Christensen whose 2008 PhD focused on equine fear. Many horses are constantly afraid or in pain during riding, and show this by trying to rid themselves of their riders. But often, their protests are misunderstood and taken as signs of good cheer or bad attitude. In the end, some horses simply give up.

Many horses are being trained for competition by methods which cause undue stress and pain to them. Impaired breathing, compressed spinal cords and constant pain from harsh use of the bit and spurs makes life miserable for our horses. Internationally renowned equestrian trainer and behavioural zoologist Dr. Andrew McLean explains.

Tail lashing and pinned back ears are signs that a horse is anything but comfortable. Yet, these behaviours are routinely ignored by riders who claim that signs of conflict are just part of their horse's unique personality. Dr. Janne Winther Christensen explains why conflict behaviour should never be ignored.

Professor Heinz Meyer's long awaited tome on hyperflexion of the neck has finally arrived. Nearly six hundred pages on the science and history of rollkur will certainly shed some light on one of the hottest topics in dressage. The author's view is that hyperflexion is principly a way of subordinating horses with complicated temperaments and not a form of gymnatic exercise. This method of control has been used for millenia, he argues, and points to ancient artwork depicting horses in the hyperflexed position. Duration 10 min.

Many horse owners don't give a second thought to adding extra vitamins and minerals to their horse's diet, if they feel it is necessary. But oversupplementation can make horses sick, so think before you scoop, warns Dr. Joe Pagan, president and founder of Kentucky Equine Research.

Chronobiology is the science of the biological clock. The natural 24 hour rhythm which tells an organism when to become hungry, sleepy or ready to overcome a physical challenge. EPONA.tv met up with Dr. Barbara Anne Murphy, a scientist researching equine chronobiology. Here she explains what is so fascinating about the horse's body clock, and reveals a few of her surprising discoveries. Duration: 8 minutes.

The Hong Kong Olympics pose a unique challenge to horses and riders because of the stifling climate. So how should a hot and sweaty horse be handled in order to help him recover as quickly and as fully as possible? Why does extreme heat and exertion sometimes cause a horse to wobble? And what exactly is the truth about hot horses and ice cold water? Dr. David Marlin explains.

Individual Olympic silver medalist Albert Voorn can't stand to see riders who have to use physical strenght in the saddle. And that includes the adjustment of their stirrup leathers. Let Albert Voorn show you how to get those smooth and effortless transitions between long and short stirrups. It's all a matter of technique. Duration: 1 min.

Modern horses are of higher quality and easier disposition than the horses which were ridden in competitions 30 or 40 years ago. So why can't the best dressage riders in the world get their horses to stand at prize giving ceremonies? Hear Dr. Gerd Heuschmann's answer to that question in part two of the interview, Dressage astray.

The rules and definitions of the FEI are being disregarded by dressage judges, allowing tense and improperly schooled horses to win international medals. So believes the German veterinarian, author and dressage rider, Dr. Gerd Heuschmann. Hear his arguments and see them backed up by slow motion footage from major championships.