Here is a video of Angela Farmer doing one of her main poses Fallen Warrior. I have been teaching variations on this shape for years and have been mistakenly calling it dying warrior. Oh well.
Call it dying warrior or fallen warrior, whichever works for you, but either way it is a killer pose. I usually use it in the middle of sequences involving the IT Band and Tensor Fasciae Latae. I’ll make a video of my own about this at some point because I teach it slightly differently but I love her approach especially the piece about the long  lower back as you move into the pose.
The beginning of fallen warrior the way I teach it is an exploration of how your muscles are programmed to work. From downward dog I ask students to take their legs, while straight, out to the side. The instruction is to go sideways not backwards but invariably the leg gets pulled backwards.
For me this is a perfect example of an overly active or dominant gluteus maximus doing the work for everything else in the surrounding area. We work a similar pattern from tadasana often with the same results. Tell your brain to move your leg sideways and you can usually watch it move slightly backwards.
Fallen warrior or dying warrior (that will have to remain my name for the pose, I can’t help it) works on a lot of levels and my favorite moment in the shape is when I am in the plankish position with leg leg out to the side and the hips about a foot off of the ground. This is where I get my work done. Even though I would like to think that I am fairly twisty, I am fairly shut down once I get my pelvis on the ground.
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