I've been doing multiple 10 minute zhan zhuang sessions per day, followed by stretching.
After a couple of minutes in the post position I feel heat/cold sensations moving across my skin and sometimes in my body, especially around the girdle area and the legs.
In the post position when I feel the muscle tension and the position becomes difficult to hold, then especially do I feel the movement of energy. I try and relax all parts of the body repeatedly, and try and go into the emptiness.
Afterward during the day I also feel these sensations, which sometimes feels like a hot mug is being dragged across my skin.
What sort of energy are we talking about exactly, am I just feeling normal post-heaven qi?
How will this practice progress, in terms of a timeline of easement of the position, in terms of the body feelings, in terms of health improvements, in terms of developing qi abilities?
Edit:
I realized that the feeling of heat flowing across the skin is a feeling I often feel during instances of drowsiness, like the moment I overcome the drowsiness and stay awake I feel the energy moving. And I've felt it in various difficult physical postures before as well.
I find this interesting, it is like the human body has a built-in mechanism that moves qi to fortify and energize the body during times of physical stress.