First, the Koan:
When a wolf is attacking you in the forest, how much force do you set free if you just think while you are not afraid?
Where is the force of muscle made from?
Next the exercise:
(Please remember that this would start with being in touch with Qi feelings from ie: Standing, sitting or lying down practice)

With natural standing: Feet shoulder width apart, arms hanging at sides, Please pay attention to "Empty Space" under both hands, and then palm of hands towards below, slowly to put up the arms to horizontal line/position parrallel to ground, in the course of doing so, please set free a STRONG desire to draw empty space as if you are lifting up very heavy iron balls, and then try to put it down gently again. Please repeat this 3-9 times.

In my practice, I first imagined it so heavy as I strained to do it, then, I understood that it was the moving of the "Qi Feeling" to the palms that was the key! Also first I did it with hand not as holding round ball but more like holding an egg and the energy ball seemed to be an egg shape and next day I did it with "Claw Position" and it felt like round ball.

At end of exercise he states, It seems to do TaiChiChuan? What does it feel in your hands, and body.

Best wishes, his Student, Pete/Scholar