Quote:
Phi Truong wrote:
if you twisted your body parts certain way, you feel you have a more connected body, i.e. winding/twisting/binding. you see similarity in various arts in the way they move, for example, corkscrew punch. the corkscrew motion wind/twist/bind your whole arm into one unit instead of a bundle of loose sticks. you will also see breathing techniques accompany such practice, because of the shock absorber affect in order to augment the muscle power and to handle the recoil force (every action has an equal and opposite reaction).

Is that the
consensus view? hm.
Quote:
Phi Truong wrote:
Force = mass times acceleration. acceleration is delta velocity (delta v) over time. yup, delta.

Acceleration is a derivative. Rewrite in terms of momentum, and they are all primary quantities, mass and velocity and potential and actual motion can be treated equivalently:
F= dp/dt
= (either) v*dm/dt
= (or) m*dv/dt (or m*a)
= (m1*v1m2v2)/dt
Effective mass (moment) changes as the moment arm changes  i.e  as the center of rotations shifts position relative to loads.
Effective velocity changes as the radius of rotations changes relative to loads.
Much simpler to see in action than acceleration. The point is not in the equations, but to see that they
objectively describe the change of centers of rotation and the change of radius  in combination. One can learn to feel these changes remotely through the body of another person  which is kokyu tanden ho. Which only works if the body is coherently connected and without discontinuities that block action and structural sensation.
If one "biggifies" one increases moment arm and effective mass and increases radius and decreases effective velocity  if one "contractifies" one decreases moment arm (effective mass) and decreases radius and thus increases velocity. But they work in spherical terms (read Kisshomaru again) S and T normal mode spheroidal waves. Imagine twisting a nerfball  it torques and shrinks  it untorques and expands. Then one can treat 'biggificaiton' and 'contractification' in progressive terms  like a snapped whip to concentrate or its converse  a wave runup on a beach  to dissipate.