This is an assisted stretch for the piriformis muscle.
With assisted stretches it is important that the client does the stretch and the therapist assists only at the very end of the stretch. When the client stretches they are using the antagonist muscles, and the principle of reciprocal inhibition causes relaxation in the muscle being stretched.
The video clip is from the DVD “Active Isolated Stretching – Assisted Stretching” by Aaron Mattes and is shown here with his permission.
Information about Active Isolated Stretching, including DVDs, books, and other products, can be found atwww.stretchingusa.com