My boyfriend and I been doing "Iron Palm" training for the past few months (although I must admit he's been more diligent about practicing.) This is a Kung Fu technique based on Wolff's Law, where repeated impact is used to help increase bone density in the hands. Traditionally, a practitioner will start by hitting a bag of lentils, then upgrade to buck shot or gravel. All the striking is controlled and gradual -- you're not improving if you break your hand. Here is my teacher's teacher Sifu Sam Ng demonstrating Choy Lay Fut fist toughening exercises:
Integral to this training is an herbal liniment called "Dit Da Jow," (say "dee daw jow") sometimes translated as "Iron Bruise Wine." Its purpose is to improve circulation, relieve pain, and increase bone density.
Now there are many formulas sold in various Chinatown apothecaries or websites, most being some closely-guarded secret formula of a minimum 20-something herbs. However, being a good scientist and the daughter of two medical professionals, this mystery potion does not sit well with me. I want to do my homework before I'm putting something on my hands every day. Conveniently, my Kung Fu teacher had recently acquired a few Jow recipes from another instructor, so I started a small research project to find out which ingredients are safest and most effective, then brew up my own batch.
Two popular Kung Fu liniment formulas I've seen are Zheng Gu Shui, and Blue Poppy Dee Dat Jow. I've used the Blue Poppy stuff, and it works well. I appreciate that all their ingredients are clearly labeled, and they all check out safe based on my research. Also, it has a distinctive curry smell. I know very little about the Zheng Gu Shui; I've just seen my classmates use it.
I started looking online, and came across a couple of interesting papers. The first, Toxicological Risks of Chinese Herbs, informed me of a few ingredients to avoid, such as Aconite. Another is a Master's Thesis on the effects of Dit Da Jow coupled with Accupressure.
Next, I checked out Half-Price Books, but it felt pretty weird to try and pull the scientific books from a shelf right next to the sections on "Crystal Healing" and "Homeopathy." My goal was to find sound scientific evidence on the safety of these ingredients, not some new-age pseudoscience.
My college's library had a couple of nice textbooks on the subject: The Pharmacology of Chinese Herbs, 2nd. Ed., by Chang Huang, and Chinese Herbs: Their Botany, Chemistry, and Pharmacodynamics, by John D. Keys. I also picked up Herbs Dymystified: A Scientist Explains How the Most Common Herbal Remedies Really Work by Holly Phaneuf, PhD, from amazon.com. Of the three, the pharmacology book was the most useful. It contained translations from the Chinese names to the scientific names, detailed descriptions of each herb, its chemical properties, effects, and indications. However, I am no chemist or pharmacist, so much of the details of this book were lost on me. Phaneuf's book was easy for the layperson to read. The only downside is it mostly covers western herbs. The book by Keys was less helpful, I just wanted to use multiple sources to investigate my claims.
Once I'd found a safe recipe, I went to get it checked out by the experts at the Academy of Oriental Medicine Austin (AOMA). For just $45, I got to visit an herbal specialist who had earned an MD in China. He took a look at my recipe and helped me scale it to the right ratio to brew one gallon. Next, I filled my new prescription from the adjacent herbal store.
Now I have a bag full of herbs, but how do you turn it into a liniment? Most recipes soak these herbs in an alcohol solution for a minimum of 6 weeks. Traditionally, the container was buried in some clay vessel; supposedly the longer it brewed, the better. Since this solution is light sensitive, I opted to use amber glass for the brewing. I found an affordable amber jug on amazon. (Don't use plastic, because the alcohol solution tends to leech bad things out of the plastic.) For alcohol, I picked up two bottles of King's Square Vodka, some bottom-shelf brand that's good enough to put on my hands. Then it was just a matter of bottling it up and tucking it under the shelf for a couple of weeks!
I'll update soon with the results! If I get permission, I'll try to post the recipe that was shared with me.
* Disclaimer: I am not, nor do I claim to be any sort of medical or herbal expert. Take this advice at your own risk, and remember, Dit Da Jow is for external use only.