Arching as extension
At a higher level, stretching moves are changed to arching moves. Arching is really a way of extension without stopping the energy flow.Arching is more stable than stretching. However, arching creates less distance than stretching.
Some examples:
- When moving the arm back towards your body, don't allow your front knee to move backwards. This way, you can extend your foot hand arching length.
- When pushing the front arm out, don't allow your rear knee to move forward. This will make your rear foot-front arm stretch longer.
Source: https://practicalmethod.com/?p=157