As I was watching my Taiji teacher demonstrate the difference to us between long and short energy it dawned on me how pointless bag work is for Taiji. In external martial arts you essentially throw your fist, foot whatever at the target. Once contact is made you tense up to make more of the impact. Bag work makes your anatomical weapons tougher to withstand their own impact into the target.
In internal the force of strike doesn’t come for a millisecond after the contact is made.
The inital contact is actually quite soft, which means that you don’t need the toughening of weapons developed in bag work.
When the force comes it feels like a electric shock because it is so fast and powerful like a pulse. This is what Taiji calls short or cold energy. It is a penetrating compression wave that can break bones and dislocate joints.
However, the opponent doesn’t move very much like when using long energy to off balance them. You see them jerk around but they are not “picked up” as with long energy. If we picture a wave, long energy is like low frequency smooth rolling wave. It picks up your opponent, uproots them and makes them vulnerable to off-balancing. The short energy is like a high frequency wave that penetrates into the opponent.
So you can practice long energy on bag to move it around but can you practice short energy? Will the bag even move much?
Furthermore, what is the point of conditioning anatomical weapons when this is besides the point for Taiji Quan?