Yin Yoga is a calm, meditative practice which employs long held, seated postures which focus on stretching the connective tissues of the body such as the fascia, ligaments, tendons and joints. It is a balancing practice to "Yang" styles of yoga such as Ashtanga, Vinyasa, or Hatha. (Yang practices focus more on muscles vs. connective tissue.) Although Yin is a slow practice it can be just as challenging as a faster paced posture practice. Stretches are deep and we are playing our edge all the time. It is important while doing Yin Yoga to really focus on what your body is telling you and never go past your edge into pain.
I found a great article from Yoga Journal on the safest way to practice Yin Yoga:
The 4 tenets of Yin Yoga1. Find an Appropriate Edge
As you enter a pose, move slowly and gently into the suggested shape—without a picture of how far you should go. As Sarah Powers says, "There's no aesthetic ideal; there's no end result we're looking for." Pause and listen to the body. Wait for feedback before moving deeper into the posture. Many people, especially dancers and athletes, have lost much of their sensitivity to the signals of the body and are used to overriding those messages. Look for an appropriate amount of intensity, a balance between sensation and space. "It's a good opportunity to create a renewed kind of innocence, a listening to the intelligence of the body that gives you feedback about when it's been triggered to feel outside its comfort zone," Powers says. Relax into the body; discover and explore each subtle layer along the way to your deep resting place.
2. Be Still
Resolve not to fidget. Don't try to fix or change the pose, to intensify it, or to escape the sensations. Consciously try to release (or even just imagine releasing) into the shape. Doing that helps you relax the muscles around the connective tissues you are most attempting to influence. In addition, moving can cause unsafe stress on the connective tissue, causing injury: To be safe, hold statically at the edge of your range of motion and engage muscles around sensitive areas or use props when needed.
3. Hold for a While
[Sarah] Powers recommends hold times anywhere from 1 to 3 minutes for beginners and up to 5 minutes or more for advanced practitioners. Use a timer so you can relax without watching the clock. Substantial holds train the mind to respond skillfully to difficult circumstances. They teach you that you don't need comfort to feel at ease. Instead of contracting around feelings and sensations, invite space and breathe steadily.
4. Release with Care
In Yin practice you put your body into long holds with joints in vulnerable positions—positions that might be dangerous if you move into or out of them quickly or aggressively. As you come out of the poses (for example, Dragonfly), use your hands to support your legs and to lightly contract the muscles that oppose the openings you've been working. It can help to do a very brief, actively practiced counterpose: After doing Saddle (the Yin version of Supta Virasana), for example, sit with your legs out straight and engage your quads.
You are challenging very deep tissues that the body usually protects from lengthening—because if they're stretched suddenly, they're easily damaged. You may experience discomfort, shakiness, and instability when you come out. Don't worry; these sensations will change.
Sara's note: I am really excited to be teaching "Restorative Flow" at Yoga North this fall. It will be a combination of long held seated Yin style postures and Restorative postures where we use props to support us. Visit Yoga North's blog for schedule information.