Taken direct from the new book ‘Master Dressage 2nd Edition‘ – for more details click the link HERE

This is probably a good place to mention BTV. No it’s not some terrible equine disease but an often-used acronym for behind the vertical. When a horse is correctly ‘on the bit’ his nose should be on the vertical or slightly in front of the vertical. If a horse is behind the vertical this could be a sign that the rider is using excessive force to position the horse’s head, or that the horse is so afraid of the bit that he keeps his head tucked in away from the contact (‘behind the bit’).

Before we give BTV a black mark and brand all riders who have their horse BTV bad riders, it is important to realise that this can happen normally in the course of training, and of course there are degrees of the problem. It ranges from the hideous and banned rollkur to being a slight amount behind the vertical. Personally, I think a lot of the correctly righteous ire against rollkur gave any kind of BTV a bad name.

The horse being behind the vertical will happen at some point with all horses and riders. The horse is carrying a heavy weight (his head) on the end of a long neck. Sometimes the horse will drop it too low if he is tired, so even amongst the best and most ethical riders you will no doubt be able to catch this happening unless they play it way too safe and trot around hollow. As a judge I always penalise BTV but it must be taken into context with other elements of the test. After all, the test is not just about whether the horse’s head can remain on or in front of the vertical throughoutthe entirety of the test. It does, however, become a problem if BTV is a consistent feature.

Some of the ways in which the horse can be seen BTV are:

• The horse was previously trained that way and rider is attempting to
  fix it.
• The horse is young, or tired and has dropped BTV.
• The horse has fallen onto the forehand and is leaning on the rider’s hand.
• The horse’s topline has become too long in relation to his underline.

There are of course many worse reasons why a horse may be BTV but I really don’t want to discuss these things: suffice to say we want to train our horses to be on, or slightly in front of the vertical, and if your horse is BTV you should know why and be attempting to correct it.