Contortion is closely tied to hand balancing in many ways. Good flexibility is needed for hand balancing. And the most contortionist acts you’ll see a variety of handstands.
Now I have no plans to become a contortionist, but perhaps we can learn a thing or two from their training. And if you are working to become a contortionist yourself, then you may find these videos and articles even more useful.
Here is a video that shows some contortion training.
I especially like the feat at the end where she is picked up while in the extreme backbend.
Probably the biggest part of contortion training is in developing a very flexible back. In this video you can see many back bending skills. Of course, you’ll also require very flexible hips legs, arms and more.
This video also speaks to the value of a good coach. With the right tips and technique, you should be able to see big improvements in your skills, in contortion and in hand balancing, or any other skills.