There are a number of products that provide further insight and value to your moving energy practise. I have included a number of these below with an explanation as to why they are so good.
Threnergy Line Strengthening Turntable
These turntables are very useful for not only enhancing the spiral lines in your legs and arms, but are also great for enhancing and strengthening your hip and shoulder bows. Additionally, they are very useful for testing your ability to isolate and feel those individual lines. You should use them in pairs, one for each foot or hand. (please click on images to access amazon affiliate product links)
Spring Flex Bar
A mini trampoline is good for testing your ability to move energy internally. With it you should be able to stand with your arms and legs straight and without bending your toes, generate a bouncing movement on the trampoline. This is actually a lot harder to do than it sounds, but is a very effective test of your internal energy capability.
A tanren uchi is a practise tool for developing strength and power in aikido. It is used in conjunction with a suburi wooden sword or ken. In Threnergy it is also a very good test of whole body power. Power is generated from spirals and bows in your body and you can use a tanren uchi to test just how good you are. Hitting the tanren uchi with external power will just create a big reactionary bounce off the tyre. There is no affiliate link here – you will need to make your own tanren uchi – but for advanced power learning it is an invaluable tool.