Rocking movements: where does the momentum come from? (Arch Rock, Bent Hollow Rock, etc)

This questions concerns the rocking movements (SL/PE2 Arch Body Rock, FL/PE2 Bent Hollow Rock, etc). To move in these otherwise static positions, some part of the body must move. The focus points aren't clear on this and its difficult to tell from the videos. So far I've tried this two ways:

 

1. Generate momentum using the head and arms; down to rock the feet up, up to rock the feet down. This keeps the arch/hollow position totally static.

 

2. Generate momentum using a sharp contraction of the torso at the extremes of the rock that temporarily pulls the position beyond its isometric range of motion, followed by a return to the normal position during the rock to the other end. This doesn't keep the position, but does involve the hips, back, abs, and glutes more so seems more in the spirit of the exercise.

 

I've generally been doing (2), but can I get a verdict?

 

 

Jordan,

 

I asked this question a while back and Keegan provided a very nice explanation here: https://www.gymnasticbodies.com/forum/topic/14130-bhbh-form-check/?p=140923

 

I hope this helps.

 

 

-Nash

I try to generate all the momentum from my core, while keeping the position as static as possible. Your second example sounds about right to me.

With HBR, I generally use a slight contraction of my core. With ABR, I generally use a slight contraction of my glutes. Once you've started, it should not take much to keep you going.