Tension | Compression

A basic forward fold is a posture I’ve been doing for years … decades, actually. It’s a simple, rather elemental shape within the human experience. Pretty much, everyone’s done it, for one reason or another. Some, as part of their yoga practice.

Usually, any limitation of range within a forward fold is thought to originate in the soft tissue — short muscles, in particular — and, this tightness prevents the full aesthetic expression of the posture. Full expression being chest lying across thighs, head to knees. And, for some, indeed, that is their experience. But, for others, myself included, while improvements in range can be made, that iconic jack-kinfe iteration of a forward fold can never happen.


Hard and soft boundaries

Bony architecture. You see, an individual’s structure determines their completed posture, not so much the soft tissues. Yes, soft tissues can be the limiter. In fact, over the months of recording my Yin yoga videos, I have experienced full ranges (on the day) of greater and lesser forward flexion. My bones certainly hadn’t changed, but my pliability had.

There are a number of reasons for experiencing tight tissues — and by the way, it’s not so much muscle that’s the issue, rather, it’s the fascia and ligaments that are the concern — but more on that another time. Some of the soft tissue length, and ease (or lack of), can be physical, emotional, chemical, mechanical. Our states change, day to day, and that’s often evidenced in our physical experience.

Generally, I’m at best moderately flexible. As such, Yoga for me was always an uphill climb, even in the most rudimentary postures. I write about this in my books, A Righteous Stretch and Fitness Straight Up. But, in short, in my long fitness journey, as a practitioner, and as a coach, I’d come to understand athletic and physical limiters, and apply such insight into improving performance in various sports, and in making daily life more comfortable.

Ultimately, when it comes to range of motion and flexibility, the shapes of the bones are what matters.

As for my forward fold:

  • First, my knees do not fully extend, or, more precisely, their full extension is quite visually bent. They cannot, without serious damage, “straighten” further. (Shape of bones: hard boundary.)
  • As well, my hip joints’ themselves prevent further forward folding. The neck of the femur effectively runs into the rim of the hip socket well before the aesthetic expression of the posture is complete. (Shape of bones: hard boundary.)

The general belief in “stretching” is that these hard boundaries do not exist, or don’t matter, rather, it’s tight hamstrings that are the culprit. (Tight muscles: soft boundary.)

But, again over decades, by using static and dynamic stretching, on my own and assisted, I have never gone appreciably farther into this posture than what’s seen here. Through my fitness career, I noticed this reality, with myself and others, and wondered…

The light bulb comes on

It wasn’t until Yin yoga progenitor, Paul Grilley, presented his ideas of bone-to-bone compression, and demonstrated with a number of tremendously divergent, but normal, human skeleton examples — pelvic and thigh bones — did I comprehend what’s actually taking place within yoga postures.

The thigh bones’ relationship with the hip bone is a complicated affair, and includes depth and orientation of the hip socket, length and angle of the femoral neck, and version (twist) of the femur shaft. The differences in the bones’ appearance revealed their owners’ physical experience, postures that were and were not available to them. Individual to individual the variation was astonishing, and I began to realize a more complete picture of what I had been seeing in in yogis’, and in other assorted athletes’ movements, but had written off to tight muscles — as I’d been taught.

Again, this put into perspective several observations with regard to sporting experiences that related to usable range of motion and flexibility. And, happily, this understanding allowed me to better avoid injury, improve athletic performance, and manage expectations for myself, and my fitness clients. Now, back to the forward fold, and many other postures, too. The range of motion we enjoy — or lament — hinges on tension and compression, in context of skeletal structure.

Something simple

If there are tensile limiters, say, in this forward fold — felt as a pulling sensation in the backs of the legs, for instance — then there is further range available. If, however, an achey feeling is felt deep in the joint (think: overly extending your elbow) then bony compression has been reached. Hard stop. The posture is complete, no matter how it looks.

Bony compression is the hard boundary, the absolute endpoint of the safe range of motion for any particular joint. The soft tissue limiters, which vary day to day — even, sometimes, minute to minute — are moveable boundaries that can be pushed back and worked through.

Either way, on any given day, whatever your endpoint is in whatever posture, just observe, and now maybe understand better whether or not you can go deeper into said shape, or whether you’ve reached your legitimate limit.


At bony compression, the posture is complete no matter how it looks. Period. That fact is remarkably hard for many to grasp, perhaps most, but it is the case. Those who’ve been conditioned to believe that by doing any posture long enough they’ll eventually achieve the full aesthetic expression of that shape may be disappointed. Or not. Maybe their skeletal architecture does allow for yoga-magazine-cover-model flexibility at some point. In any event, you’ll know by feel.


All that said, going as deeply into whatever posture, and staying there for however long — minutes, as in Yin yoga — certainly results in myriad athletic and yogic benefits. Perhaps even enlightenment, in one form or another.

But, in my case, far short of spiritual awakening, and relegated to an open clamshell of a forward fold, my Yin yoga practice always delivers a righteous stretch! And, I’m okay with that. (Hmmm, maybe that’s the awakening.)