I remember reading an article couple of years ago by a yoga teacher who observed a tendency to give too much anatomical instruction in yoga classes. As expected, she got a lot of heat from other teachers who passionately commented that detailed anatomical instruction is absolutely necessary to avoid injury, to get the student deeper into the pose, etc.
Personally, I would frame the problem a bit differently. I believe that there is often not enough “why” in yoga classes, which is being compensated for and overshadowed by “how”. The consequence of this approach is that many students have memorized where each body part should go in each individual pose (including where the thumb is pointing), but have very little understanding of why we do the pose in the first place. That is why we have great fascination with forms of poses at the expense of function.
In my tradition it is always the opposite. We start by understanding what the pose is meant to accomplish and then based on that guide the student into the form of the posture. Whatever we do in yoga we need to do for a reason, otherwise why bother? That is why when we describe a pose, we always start by identifying the position of the spine, since the position of the spine gives us immediate clues about what the pose is meant to accomplish.
I am sensing that there is still some confusion among yoga teachers as to why we need this sort of classification. For example, one point I hear often is that there is no such thing as a pure lateral bend; there is always an element of rotation in it. OK, sure, but we are missing the point here. This type of classification is important for understanding the function of individual poses, it is not about the purity of the spinal position itself. Utthita Trikonasana is classified as a lateral bend because it shares the same intentions with all other lateral bends (to stretch and strengthen the lateral structures of the torso, to facilitate deeper breathing by working the intercostal muscles and expanding the ribcage, and so on). Does it have a bit of a spinal rotation in it? Sure; yet when we perform the pose we focus on the lateral bending and try to minimize the rotation to protect the lower back and sacrum. Janu Sirsasana has an element of lateral bending, but it is mostly a forward bend; Adho Mukha Svanasana has an element of forward bending, but it is mostly an axial extension posture; and so on. Knowing where the pose belongs classification-wise helps us understand both why we do it and how to teach it.
For the past year we’ve been covering all five directional movements of the spine from every angle. We have finally reached the end of this journey and here is a summary of the five directional movements of the spine and what they are meant to accomplish.