In SKD we use Tai Chi body structure.
One of the principles of Tai Chi body structure is 含胸拔背 commonly translated as contain the chest, raise the back.
Here I give a demonstration of what this means and the implication in power generation.
I didn’t hit the dummy harder as I didn’t want it to fall over in case you are thinking that the power is not that strong.
I also kept the demo to this principle instead of involving the other principles so that we can view in isolation the workings of this principle.