I'd like to see an explicit discussion of that topic [spiraling]. Where does the power come from? How does it spiral?
I can talk a little bit about "spiraling", but I'm not going to pretend that I have a complete understanding of it. In fact, I reserve the right to be wrong and/or change my opinion in the future.
OK, so *one way*
to conceptualize internally-powered movement is to map it along two axis. The first axis is the "vertical" axis, and I call it that because it relates to a vertical movement or rotation of the center. Outwardly, "vertical" movements correspond to extending/contracting the limbs, arching/rounding the back, and looking up/down. Internally it corresponds to a sense of rising and lowering "energy".
The second axis is the "horizontal" axis, which--you guessed it---relates to a sideways movement/rotation of the center. Outwardly, "horizontal" movements correspond to rotational or twisting motions, such as "rolling" the hips and shoulders in/out, twisting the torso, turning over the wrists, and looking to the side. Internally, there is a sense of "winding" in/out, and that's where "spiraling" comes from *as I currently understand it*
If you look at the "Anatomy Trains" model
that maps the various muscle-fascia pathways, you'll notice that there are lines that run straight down the front, back, and sides, as well as lines that crisscross around. Those straight lines are the ones that generally come into play with "vertical" movements. The crisscross-y lines---that quite literally "spiral" around the body---are the ones that generally come into play with "horizontal" movements.
Furthermore, you'll notice that those straight ("vertical") muscle-fascia lines are, umm, "one-sided". Meaning, you have lines that run up the right side, and lines that run up the left. The crisscross-y ("horizontal") lines, however, cross from side to side. This is why "cross-body" training relates to "spiraling".
Now, in the big picture, training "windings/spirals" is the same as "straight" connections (*IME/IMO*
). You just connect through and work those crisscross-y muscle-fascia lines. But IME, it can be tricky to learn how to engage those spirally lines in the beginning, and the exercises you regularly practice play into that.
, I first started to understand this type of movement by practicing "sideways" oriented motions that work a cross-body connection. As I get more familiar with "spirals" in big, obviously sideways movements (like Chinese silk-reeling), I also start to see more subtle spirals in movements that otherwise appear "straight" (like in a karate punch).
So here's the exercise my old teacher recommends for learning sideways movement (which I still practice a lot): Stand with your feet about shoulder width and a half wide, feet parallel and pointed straight ahead, and knees slightly bent. For now, just let the arms hang at the side, in a relaxed but connected manner, if you know what that means.
The exercise consists of simply shifting your hips from side to side, so that your weight is balanced maybe 70%/30% at the extremes, while keeping the spine upright. But here's the important part---you need to keep the hips straight and level, as if they were skewered on some sort of pole. This sounds incredibly easy until you watch yourself in a mirror. What feels "straight" actually causes the hips to get all twisted up.
What you have to do to make this work is turn the leading "knee" in, and the trailing "knee" out, but there's some trickiness involved. To do this correctly the movement has to come from the hip joints themselves. It's more than just "twisting" the leg---it actually involves changing the position of the femur head inside the hip socket by "rolling" it back and forth.
When you do the femur head thing correctly, the knees rotate, but they don't otherwise move around. (Oh, and the trailing leg does slightly straighten and the leading leg slightly bends, if it wasn't obvious.) Watching for knee movement is one way to gauge your correctness, on top of watching the straight- & level-ness of your hips.
A word of caution, however---there's a good chance you'll have to loosen up the hips/groin/lower-back areas a bit before you'll be able to do this properly. Tension in the aforementioned areas will cause the knees to get torqued. (But miraculously, if you remove the tension in those areas, you'll feel nothing in the knees.) So in the beginning, go really light until you figure out how to release those tensions, 'cause otherwise the exercise will cause sore knees.
Now, what I've described above is the mechanics of the exercise, but not the all important feeling. When you learn to do the exercise with the correct form---which also involves spine stretching and all the other general advice you'll hear elsewhere---and with an ever increasing level of relaxation (and connection, if you know what that means), then you begin to experience an "opening" and "closing" sensation in the pelvic crease. That is to say, you'll start to experience an "expanding" or "pushing" feeling in the trailing leg, and a simultaneous "contracting" or "pulling" feeling in the leading leg, that seemingly "winds" the legs in or out, respectively. If you're focusing on the connection between the legs (the "lower arch" as they call it in the Aunkai), then it might feel as if "something" is being "passed" from the leading leg to the trailing leg through the lower abdomen. In time, you might also feel a little spot of pressure moving horizontally across your abdomen (that's the center).
It is this rotational "open/close" or "winding" in the hips that leads to "spirals", *as I currently understand it*
. As you become more familiar with this "winding" feeling, you can begin to learn to engage this "opening/closing" independently (somewhat) of any external movement. You also learn to connect the "winding" in your hips out to the extremities, which is when you get the sensation of a whole-body "spiral"... That's my working assumption, at least, I'm not quite there yet. (I get whole-body movement, but it's still difficult for me to overtly
feel the connective lines in the legs.)
What I've described here is only the beginning, developing whole-body "spirals" that stretch from foot to hand takes time... like, a few years. I also suspect that there are deeper elements to all this that I haven't yet grasped, but I'm confident that will come with time.
I did a good bit of shiko with Ark in Atlanta but I don't recall any mention of spiraling related to it... How would shiko develop spiraling power...
I'm not too comfortable giving advice on shiko, but I'll make a couple points.
The way I *currently*
understand shiko is that it's kinda like 2 exercises rolled into one. The "squat & clap" section seems like one bit, and the "shift, raise, & stomp" like another. The way *I experience*
shiko is that the "squat & clap" portion seems to primary work a vertical rotation of the center---down the back and then up the front---while the "shift, raise, & stomp" part primarily works a horizontal rotation. (I can tell that there's a general horizontal movement in the center during the "shift, raise, & stomp", but it's still difficult for me to discern the exact "route" that the center takes. Sometimes it feels like, uhh... like it *might*
just maybe be moving to one side along the front, before circling around through back horizontally... or maybe I'm just imagining that, it's difficult for me to tell.)
As such, if you want to emphasize the spiral-y parts of shiko, I think you have to practice it a bit differently from the way it is normally explained by the Aunkai, particularly the "shift, raise, & stomp" portion. (But even though the normal Aunkai description doesn't include "spirals", if you watch Ark, he'll often throw in the winding elements.) But I'll leave it to others more experienced than I to explain how to do that.