I agree, the two are related. In the training sequence I follow, you start collecting and lengthening, and slowly work up to the true extended trot. The true extended trot requires the horse to be able to collect and then move out at full speed with the shoulder girdle lifted.
Passage and piaffe are ultra collected movements that typically aren’t fully attained until later, but people do teach the beginning of piaffe fairly early to improve the gaits overall.
The thing to remember is that these are all natural movements that most fit healthy horses will offer at play when they are sufficiently excited. My own Paint mare does a gorgeous passage, floats above the ground. The catch is that she only does the passage once a year, for about 5 minutes, when I first let her out on the field with the herd for her annual pasture vacation. Otherwise we really can’t get the impulsion out of her in a controlled situation.
So the big challenge with training these gaits under saddle is how to get the impulsion for these developed gaits out of a horse that is calmly following your instructions, not losing his mind with excitement.
If you are seeing suspension in your horse’s trot gaits, that’s a good sign for dressage. The extended trot should also have a moment of suspension, it isn’t a flat racing trot. They go together.
I don’t think that suspend and extend are antithetical.
Are you perhaps thinking about extend and collect?
It’s important to keep in mind that the top international dressage horses these days are Warmbloods who are both bred and trained to showcase an exaggerated extended trot which is not possible for most horses (even most Warmbloods) and is arguably pushed to the extent of being unbalanced. There is a corresponding diminished focus on correct collected work.
If you want to see another kind of horse, you might be interested in looking for videos of Iberian horses, that is Andalusian, Lusitano, and crosses. You might find some interesting videos in Portugese and Spanish Working Equitation competition, which has an exciting trails obstacle speed component and also a dressage phase.
These are horses for whom.collection is factory installed, and who have varying natural gaits. They will never move like a spider legged high end WB but they can absolutely do a correct extended trot.
I suggest Iberians as a reference point because they are smaller and more compact than WB, but also because Iberian blood from Spanish horses was the foundation of the mustang population from the 1500s to the 1800s. Over the late 19th and 20th century, the feral Western horses got mixed with a lot of settler horses, draft and TB and ranch horse. In isolated places like the Kiger Reserve in Oregon, the Iberian blood is more obvious.
So if you have nice mustangs, chances are they will have some Iberian characteristics, and those will provide a good reference point for what is possible in a compact, collected, athletic, smaller horse.
If you’ve never seen Portuguese/Spanish Working Equitation, I bet you will love it!
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