Some Qi Exercises with commentary from Mike Sigman

 Mike Sigman's comment:

this movement is the essence of power store and release in Chinese Martial Arts. He's basically using a reverse breath to pull up the elasticity from the Huiyin/Perineum, pull it up to the Mingmen, and then release with an exhale as the store area at the mingmen drops forward into the abdomen. 

 
Hun Yuan Qigong from Mike Sigman on Vimeo

Stepping Exercise

I learned this stepping exercise from Chen Xiaowang back in the 1990's, but I didn't understand it very well and therefore didn't do it very much. Now I do it a lot more. I assume it's a fairly standard Chen Village exercise because Chen Bing showed it to me, also, and I saw a video once of someone else from Chen Village doing it.

It looks fairly simple and I don't want to over-describe it, making it seem complicated, so let me just say a couple of things:

As in all the Chinese martial-arts, you should constantly keep your weight and the weight of anything you hold or lift in the sole of your foot/feet ... without ever letting the forces rise above the soles of your foot/feet. If you're just standing, always allow your complete weight to rest in the soles of your feet. If you're holding something, feel the weight of that something always resting in the soles of your feet. If you lift a leg for a step, feel the rising leg's weight rest in the sole of the other foot. And so on. If someone put their hand on your rising leg, they should feel the sole of the grounded foot.

As you lower the raised foot, let your weight first sink into the grounded foot, going into the other foot only when it is positioned properly.

This exercise will stabilize your walk and balance very well. It's the first exercise I do in the mornings.

I like to inhale as put my weight onto the new foot, pretending that my leg is a suction-hose pulling my foot down and tight into the floor. The inhale also pulls up the tissues that are lifting the other leg. FWIW 

Stepping Exercise from Mike Sigman on Vimeo

Chen Bing reportedly using the same stepping movement as part of a form
Master Chen Bing’s 13 Energies Form from Embrace The Moon on Vimeo.

Stepping Exercise: Part 2
I said that I did the slow stepping exercise, just about every day, as a warmup, but I usually transition into another forward and backward stepping exercise that is taken from the Oblique Walk and the Step Back Whirl Arms (Repulse Monkey) of the Laojia Yilu. I'll put a brief clip of Zhu Tiancai showing the movements from the form; mine look slightly different, but it's the same natural winding of the body. The idea is to do the stepping while including the whole-body winding and unwinding (Open and Close) as it moves.
When you're moving forward, as an example, think of your molecules as all moving forward as one group, but imagine/feel that there are elastic spider webs attached to each molecule, slightly resisting your forward movement. Same idea as imagining moving through water, more or less, but I like this particular visualization sometimes.
BTW, a lot of people forget the imagined resistance to the legs (like "Mud Walking" in Bagua). It's important, though.
   

windinggong from Mike Sigman on Vimeo.