Hojo Undo methods are a category of "supplementary exercises" (involving specialized equipment) that are utilized in Okinawan martial arts. Most of these methods fall into one of two categories: 1) weight resistance tools for "functional strength" training and 2) tools which involve various types of impact conditioning. Most of these methods had a long history in China before they were imported to Okinawa.
Anyway, everyone is invited to join:
There is another webpage that is quite closely related that I wish to bring to people attention. It is called Martial Makers and this is how the site describes itself:
"Martial Makers, a website devoted to do-it-yourself martial arts training equipment.
This site will feature links to great examples of DIY projects from around the internet as well as original how-to guides for making your own high quality martial arts training gear at a fraction of the cost of purchasing similar equipment, and using materials that are easily available.
Curious about how to make your very own traditional training implements? Want to create a custom, home-made version of an expensive modern training apparatus? Love duct tape? Then you’ve come to the right place!"
Here is the link:
The "Martial Makers" Webpage
So now that you've visited these pages and have built some equipment the question is "how do I use it?" Here is a YouTube playlist that will show you the basics (and even a bit that is not so basic):
I hope that you find these resources useful in your journey.