Here's an interesting theory by a Danish nutritionist:
“A Happy Athlete” or an “Addicted Sports-Tool” for the Top-Rider?by Eva Lydeking-Olsen, Denmark
Quote:
Horses are moving with laborious/ heavier breathing, specially in canter and collected work,
indicating suboptimal oxygen supply, less carbondioxide exchange. The possible effects are:
* Endorphins have a painkilling effect, so the horse can be trained harder, without protesting or
experiencing obvious discomfort or pain.
* A horse showing conflict behavior, despite under influence of higher levels of endorphins, is
really telling something about compromised welfare. Rollkur ridden horses often show conflict
behavior in different situation, but the technique is forcing submission onto the horse.
* Working with high levels of endorphins might mask minor damages to the horse.
*Beta-endorphin is able to create a mood of euphoria and the horses might become “training
addicts”, but on the basis of a brain-chemistry reaction forced on by the rider (by draw reins and
hard use of bits and spurs) - not a true development of collaboration between two living beings
6* Morphine medications ad endorphins is strictly forbidden acc. to the doping-rules and rollkur
might be a way of creating an “endogenous doping” – the horse itself, by the extreme training,
creating high levels of powerful, medically active beta-endorphin??
* This could (partially) explain the hyper- reactivity also observed in many rollkur ridden horses:
Conflict behavior during prize-giving ceremonies as a consequence of withdrawal, irritability and
mood swings due to fluctuating levels of endorphines??