Why work with cold muscles? Everyone always wants to know why yin yoga is supposed to be practiced in the early morning and before warming up – especially since most other forms of yoga demand warm-ups prior to attemtping to stretch at all. As delicious as I find a yin practice, I’ve sometimes struggled to explain the biomechanics that seem so counterintuitive yet feel so great. Recently I came across an article (not about yin yoga) from Roger Cole that gives a simple and concise answer that makes sense of the cold-muscle directive. When our muscles are hot and fatigued after a vigorous workout, you may actually make your connective tissue so flexible that its molecular structure can be easily torn apart by vigorour stretching. In addition, the fatigue makes it more challenging to monitor and control the degree of stretch. Of course, Cole goes on to note that stretching while cold has its own risk because the cold tendon is less flexible and has less blood flow than a warm one – but the crucial distinction in a yin yoga practice is that we are not attempting to stretch the tendons and ligaments- we are actaully working – gently, slowly, and mindfully – with the connective tissue surrounding the muscle. Because of this distinction it is optimal to work with cold muscles- it bypasses any chance that we will overstretch tendons.