- Hi Bernie! I have a question-a regular student of mine asked if I had any scientific research to back up the claim that yin yoga is a form of acupressure .. or rather, that acupressure is an effective way in stimulating tissues energetically. He's become a regular for my classes and usually enjoys challenging the mystical side of yoga nidra (I guide this for 30 min after the yin), but now he's turned to challenging the science supporting yin / acupressure treatment would you have any resources you could point me toward?
thank you,
Katherine
This is a good topic for discussion. Your student is asking if there is any scientific proof that acupressure works. The short answer is - Yes! But, a longer answer will take some study on his part to understand why the answer is yes. Let's stick to the scientific evidence rather than exploring all the Daoist experiences and the TCM map of chi, energy, meridians, etc. (Although, we certainly could go there too!)
In this Forum, there is a subsection on Yin Yoga and Energy, and I would invite your student to peruse all that is available there, such as this thread on Acupressure Points. And, in the Science behind Yin Yoga section, there is this thread Yoga Improves and increases Qi levels in acumeridian meridians .
But, my go to resource is Helene Langevin, who studies acupuncture and long held static stresses (i.e.: yin stretches, although she does not call it that.) I would highly recommend your student read her article in The Scientist called The Science of Stretch. She doesn't use the term acupressure, but she does report on these effects, which she calls mechanotransduction. She reports, “Through these cell-matrix connections, cells sense forces and transform these mechanical signals into cellular responses such as the activation or deactivation of signaling molecules, translocation of transcription factors into the nucleus, and ultimately, changes in gene expression. In addition, substantial evidence supports the notion that mechanical signals can be transmitted directly through the cytoskeleton into the interior of the nucleus., This graphic from her article is quite informative (notice the figure on the right...doesn't that look like a yoga pose? )
When connective tissue stretches
Regarding meridians, she says, “The mysterious “acupuncture meridians,, defined as lines or tracks connecting acupuncture points, also may be related to connective tissue, as they seem to be preferentially located along connective-tissue planes between muscles, or between muscle and bone. We have found that more than 80 percent of acupuncture points in the arm are located along connective-tissue planes. This makes sense, since loose connective tissue houses blood vessels and nerves, suggesting that mechanical stimulation of connective tissue generated by needle manipulation could transmit a mechanical signal to sensory nerves, as well as intrinsic sensory afferents directly innervating connective tissue.,
This work by Langevin is certainly not the whole story. She is examining just one aspect of acupressure: mechanical stress. However, other researchers are looking at the electrical effects that stressing tissues creates. Through piezoelectricity and stress generated potentials, when we stress our tissues we create tiny electric currents in the tissues. These currents are another form of communication which cells respond to. Bones grown stronger and thicker thanks to the currents created when you stress your bones (this was discovered in the 1800's by Wolff and a law was named after him that describes how bones adapt to stresses.) Your student can learn more about this in chapter 7 of my book The Complete Guide to Yin Yoga. That will give him pointers to other research, such as James Oschman's books on Energy Medicine.
I hope this helps!
Cheers
Bernie