A more meditative approach with a physical focus much deeper than Yang like practices.
Yin Yoga postures are more passive postures, mainly on the floor and the majority of postures equal only about three dozen or so, much less than the more popular yang like practices. Yin Yoga is unique in that you are asked to relax in the posture, soften the muscle and move closer to the bone. While yang-like yoga practices are more superficial, Yin offers a much deeper access to the body. It is not uncommon to see postures held for three to five minutes, even 20 minutes at a time. The time spent in these postures is much like time spent in meditation, and I often talk students through the postures as if they were trying to meditate. While in a Yin class you might notice similar postures to a yang class except they are called something else, on a basic level this is to help the students mind shift form yang to yin, active to passive.
This concept of Yin yoga has been around for thousands of years and some of the older text, such as the Hatha Yoga Pradipika notes only sixteen postures in its text, which is far less than the millions of postures practiced in today’s yoga. In addition, having read much of these text and also cliff notes from various teachers it would appear that these “postures” were more yin like to help promote meditation and long periods of pranayama and sitting. Now I am not claiming to be an ancient text yoga guru, but this is just an observation I have made.
So what exactly is Yin yoga? It is a more meditative approach with a physical focus much deeper than Yang like practices. Here the practitioner is trying to access the deeper tissues such as the connective tissue and fascia and many of the postures focus on areas that encompass a joint (hips, sacrum, spine). As one ages flexibility in the joints decreases and Yin yoga is a wonderful way to maintain that flexibility, something that for many don’t seem to be too concerned about until they notice it is gone.