This exercise is one of my favorites, and I refer to it as "Headphones". You'll see why shortly in my awesome diagrams below.
I really like this exercise because it forces the horse to step under themselves laterally. When done correctly, they really bring their backs up and are wonderfully on your aids when you are done. This exercise also calls for some lateral difficulties but if your horse isn't ready you could easily break the exercise up and do it in different parts before stringing it all together.
You're going to start off walking/trotting/cantering/whatever floats your boat-ing left. Once you get a little less than halfway down your long side, halt (at the orange dot). Bonus points for a square halt.
|Guyz I'm getting so good at Paintbrush|
After halting you are going to proceed to ride a semi-circle using lateral movements only. If you can manage this without any forward or backwards steps you win all the things. Obviously this is a lot to throw at a horse at once, so like I said before, if all you can get is a few steps and then walk off, no worries.
So once you've halted you're going to apply right leg, step into your left stirrup, and encourage your majestical unicorns to side step left. I try to get in two steps of straight side pass before focusing my efforts in moving over Mollie's rear end. During the "corners" you want their hind ends to cross over and their front ends to more or less stay in place. After a step or two of "haunches over" you side pass left for another two steps, then another corner, then another two side pass steps to the wall. Halt at the orange dot.
|Purple slashes denote lateral-ness.|
Now if your beasts are anything like Mollie they will be ALLLL sorts of puffed up by the time they get to the wall. She's usually offended that I asked for so much lateral motion but at the same time she's reallllllly nice and on my aids. So it typically doesn't take much encouragement to get her to go forward. Either walk/trot/canter off from your orange dot to the right, ride through the short side, and halt a third of the way down your long side (orange dot).
From here you're going to repeat the "headphone" portion of the exercise but to the right. So you will apply left leg, stand in your right stirrup, and step away from the wall towards the right. Two steps to the right, one or two haunches over through the corner, two steps over, two haunches over to corner, and then side pass right to the rail.
Halt once you get back to the rail, then charge your steeds forward again and do it over and over! Or if it sucked do it never again.
Why this exercise works: There is soooo much lateral motion in this exercise it's practically impossible to be detrimental. All the sideways motion is wonderful for getting you horses up and under you and this exercise allows for plenty of it.
Why I like this exercise: This exercise is really awesome for days where Mollie just needs an ass kicking. And that sounds bad, but ever have one of those days where your horse just isn't really on your aids/isn't really trying/is tuning you out? Yeah, not easy to do in this exercise. It really gets her moving, gets her working, and it's not very complicated.
Once again, please let me know if you incorporate this and how it goes!!