Thanks Jonathan for your GREAT explanation. What would be nice now would be if you could explain how we attain and release that energy . Most of us have some understanding as to what takes place,but it is not clearly set in my mind.

This is one of those things that's much easier to demonstrate than to describe.

I'll use bowling as an analogy. If you simply roll the ball out of your hands (ie "old lady tyle"), the ball rolls slowly down the lane. When it hits the pins, it tips them gently, and usually only the ones it makes direct contact with.

To really send the pins flying, you need a lot more speed. You cock the arm back, then swing it forward before releasing the ball. It also helps to move the entire body forward through space (by taking a step or two) as you swing the arm.

Likewise, in ballroom dancing, to "release" the rotational swing (ie CBM), you need to wind up beforehand (or end the previous movement in a wound-up position). Without wind-up, there's nothing to release, and you end up with a slow, controlled movement, like "old lady bowling", or trying to push a swing from the bottom.

An exercise you can do to help you with this concept is to begin standing with arms extended to the sides, feet pointing to line of dance. While standing in place, turn your body to face diagonally to center, so that the left arm is positioned behind and right arm forward. This is your wind-up. Now begin to swing your left arm forward while at the same time stepping forward on your right foot. Time the rotation to the movement so that you end square to the line of dance (arms straight to sides) when the body weight has arrived completely over the foot. Continue rotating and traveling so that you take a second step (feet all the while still pointing to line of dance), finishing with the body facing diagonal wall.

The arms should feel active but not actually disengage from the body. When I say that the left arm is positioned back, it's not actually reaching backwards. It's simply behind the body in space, with respect to the line of dance. The arms are merely extensions of the body, and represent its orientation.

Two things will help you feel the "release of energy":

(1) The first step should have enough energy that it sends you right past the first foot and on to the second. That's not to say that the second step shouldn't have any energy or leg muscle usage of its own, but a good amount of energy of the second step should be residual from the first.

(2) Try to feel as though the release of rotation is the motivating force behind the step, and not vice-versa. A common mistake is to begin moving before releasing the rotation. If need be, do the opposite to train yourself out of the habit. Start swinging your arms first, then start your step. Just make sure that you don't over-cook the rotation -- it still needs to be timed to the progression so that you end squarely at approximately the same moment your weight arrives fully over the first step.

Regards,
Jonathan

Thanks Jonathan. Dave

i love dancing its so fun

"To really send the pins flying, you need a lot more speed. You cock the arm back, then swing it forward before releasing the ball. It also helps to move the entire body forward through space (by taking a step or two) as you swing the arm.

Likewise, in ballroom dancing, to "release" the rotational swing (ie CBM), you need to wind up beforehand (or end the previous movement in a wound-up position). Without wind-up, there's nothing to release, and you end up with a slow, controlled movement, like "old lady bowling", or trying to push a swing from the bottom."

It's worth considering that while there is body rotation invovled in sending a bowling ball on its way, the ball itself follows a straight path through the swing - you would not swing it along a horizontal arc and hope to release it going in the correct direction. In bowling, the ball is the "center" that matters. But in dancing, it is the body's own center that matters. There is a rotary action during the CBM step, but the body center itself moves along a straight path down the floor even as the side (or hip) that is leading changes over the course of the step. This is not a curved path around a fixed external point, but a straight path of the body center, with the body rotating around that moving center, rather than around an external point.

That actually depends on the action. The one we're using mostly in our example, the forward half of a natural, is a good example of this. However, there should be some curve of direction on the CBM on the back half of a natural, as well as either half of the reverse (the back half having the stronger curve of direction). If both parties move on a straight line, they rotate independently, rather than rotating around a common center, and the dance position is altered.

At any rate, the curving of direction is probably the one aspect of CBM that doesn't actually swing, because the direction that the center travels when curving is hardly a release of energy through that particular arc. So that point may be irrelevant to this discussion, but I do mention it because we don't want to mislead people into thinking that all (or even most) CBM movements occur on a straight line. But let's assume that they do anyway, or at least look specifically at the one example where the direction is straightest, the forward half of the natural.

You make the point that the arc of swing is not literally about a fixed axis outside of the body (as though you were hanging onto a pole and circling around it), but that your body just happens to be rotating while traveling a straight line, and I do concur (at least with the forward half of natural). But that doesn't mean it can't still be thought of as a rotary swing. You can stand in place and rotate, and if you do so with enough energy to release (in other words, enough that momentum takes over what the muscles began), you're producing rotary swing. It's a relatively small arc, but then swing is not defined by the size of the arc.

The fact that you are also traveling forward broadens the arc through space, but does not affect the axis. You are not swinging around a remote axis, but rather swinging around the same axis you would be even if you weren't traveling... the difference is, now it's a traveling axis.

None of this, however, prevents people from feeling as though they are swinging around a remote axis (fixed point outside of the body). There's nothing wrong with having that impression, even if it's not an accurate description of the true physics behind it.

Take, for example, the idea of pendular swing. The very idea is ridiculous. You can't have true pendular swing unless you hang from a fixed point above. I don't know anybody who swings from a vine while ballroom dancing, but that still doesn't stop people from describing the action as "pendular". And that's perfectly fine, if it produces the right results.

Here's my point: I can't disagree with physics. But whether the axis of rotation is real or imaginary is not as important as whether the impression it leaves on a dancer is the right one to produce the intended result.

Regards,
Jonathan