"Horses mirror the feelings people try to hide," the pioneer in the discipline, Linda Kohanov, who runs the Epona centre in Arizona in the United States, told AFP. "They teach relationship skills."

Two main disciplines come under the equitherapy umbrella -- equine-facilitated psychotherapy and equine-assisted personal development.

But therapeutic work with horses does not necessarily involve riding, said Brigitte Martin, co-president of France's Equine-Assisted Therapy Federation. "It can happen during grooming, or with the horse on a long rein. The horse acts as a mediator between the therapist and the patient."

Martin works with children who are autistic or blind or deaf, and facilitates their contact with a pony. "The child becomes less agitated, and more relaxed," she said.

Equitherapy can improve posture and well-being, added Josee-Laura Delacoux of the French National Equitherapy Society SFE. "You see people opening up, smiling more. Horses are very sensitive. They pick up on emotions, without being judgmental, and this allows people to express themselves."

Claire Morin, from the French association Cheval Contact, says riding itself is not essential, but can be important.

"People's lives can be transformed by interaction with a horse. They see how they communicate with others, and what they need to change in themselves. They learn how to say no, and set limits, but in a natural way, without a power struggle."