Yin Yoga is a slow-paced style of yoga as exercise. It is important to practice it when we are cold (not as a stretching session after a workout) in order for it to be beneficial for our deep connective tissues. It incorporates principles of traditional Chinese medicine, with asanas that are held for longer periods of time than in other styles. It is common to hold asanas for anywhere between 2-20 mins and therefore it is slow and meditative.
While “yang” yoga (Vinyasa, Hatha, Ashtanga, etc.) focuses on our muscles, yin yoga targets our deep connective tissues - fascia, ligaments, joints, and bones. It is an important type of practice to incorporate in your routine if you are trying to increase your mobility and flexibility as it stretches and lengthens the rarely used tissues in our bodies. Many of the postures focus on areas that encompass a joint (such as the hips, sacrum, and spine, etc.).
Because we are holding the poses for a longer period of time, yin yoga also teaches us how to respond rather than react by breathing through discomfort, sitting with our thoughts and tuning into the physical sensations of our bodies.
The practice of yin yoga is believed to open up energetic blockages in our bodies. This is based on ancient Chinese philosophies and Taoist principles which believe there are pathways of Qi (energy) that run through our bodies and by stretching we are releasing that energy and helping to restore a healthy flow of Qi. According to Stefanie Arend it can have similar effect to acupuncture treatment.