To follow up with my previous post, I  am really pleased to be able to share with you this really insightful article. It takes a little bit of concentration to understand but it really worth it so as to picture out the way the top line functions - freely and less freely - the biomecanic of working low and round, in its different conceptions, rollkur and classical. 
I am thankful to its author, Peteris Klavins who also works with my trainer, Isa Danne and who is an uncredibly devoted biomecanician.


   Within the framework of the debates concerning certain Methods of Training at least disputed and of that one of the necessary clarification in the mind of the Lightness promoted by Allege-Ideal, it seemed to me useful to gather and to present some schematizations allowing to specify certain « equestrian terminologies » in regard to anatomical references clearly differenciated, as to illustrate in a practical way some functional comments relative to certain practices of gymnastical work of the horse.Indeed, and quite particularly as regards to the work said Low and Round, it seems that it reigns since a good many of years a big «VAGUENESS» as for the meaning attributed to it by such or such user of this terminology, this vagueness allowing maybe to some to connect in a discretely undue way some personal practices to certain «justifications biomechanicaly demonstrated» relative to a work of the horse «really low and round in its whole» and not only «round» at the level of its neck...

For my part, while a great number of riders associate by custom the concept of «LOW WORK» to exercises of the horse in overbending on an 
extension of the Cervico-Thoracic Hinge as illustrated by the schema #6 of the following series of drawings there below, it would seem to me more adequate and more logical to reserve the use of this functional terminology of «LOW WORK» only to the exercises in lowering of the neck, the horse presenting an objective flexion of its Cervico-thoracic Hinge as illustrated on schemas #1, #3 and #5 of the same series. ( In practice, to give ourself a convenient reference, it is simple to observe if the location of the cervical joints C2-C3 is situated above or below the withers...)

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It is a very good thing, between exercices and at the end of work, to stretch the topline of your horse and release it from any tensions.
But you still have to do it in a thoughtfull manner, keeping soft contact, a relaxed jaw and a poll free of tensions. Then, you have to make sure your horse is not moving his balance to the forehand.
Stay focus on your circle, or on your line and make sure your horse is also straight and does not collapse on any side.

While keeping this chewy contact, try to have the horse open his frame, more than just having him go down.
Not only will this exercise improve throughness, it will also improve the complicity between your hands and the horse mouth - having a horse that trustfully follow your hand, wherever it is.



Here are two pictures :

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INCORRECT STRETCH - horse weight too much on the forehand, low activity from the hind legs, neck could use more lengthening.
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BETTER STRETCH - horse more balanced, good activity of the hindlegs, topline gently working. Neck could lengten a bit more, but that's still good considering the early stage of training - hence the petting !