Tension versus Compression: the Safety Line for Yoga

by Baxter

An essential ability to cultivate when adding yoga asana to your health regimen is the differentiation between sensations that are potentially good for you, such as the healthy stretch of a tight muscle, and those that are potentially injurious to you, such as overstretching a tendon or ligament, or compressing structures to the point of injury. We are going for the former and trying to avoid the later.

Two of these sensation creators, tension of a stretched muscle and compression of soft tissue or bony prominences, have been the subject of a quite fascinating yoga video by Paul Grilley, entitled “Anatomy of Yoga.”I viewed this DVD many years ago now, but this essential differentiation between feeling tension and compression and its importance to practicing safely has stayed with me. I’ll let Paul tell you more about it in this youtube video:

Experiencing tension or stretch sensation in a muscle is generally a desirable feeling to become familiar with, especially if it is experienced in the mid-portion of a muscle, farther away from the almost inelastic tendons and ligaments that tend to be located closer to the joints. A typical place to become familiar with this kind of body sensation is the hamstring muscle at the back of the upper legs. I chose this intentionally because it is an area that most students feel some sensation when in Downward-Facing Dog or Standing Forward Bend, just to name a few poses that stretch the hamstrings. As most of you know, the intensity of the stretch sensation can be quite strong, and yet it usually does not mean you are injuring yourself. 

The hamstrings are located on the posterior part of the hip joint, so when we are doing a stretch of this muscle group, the structures on the opposite side of the joint, here being the front of the hip joint, are brought into close proximity to one another in Standing Forward Bend. The closer the pelvic bone and the femur bone come together, the greater the chance for everything in between those two bones are to be compressed or smashed together. As far as differentiating between the sensations of stretch and compression, my personal experience is that they feel distinctly different.  Compression really does feel like things (muscles, skin, tendons, ligaments, fascia and bones) are getting smashed together. And sometimes it creates a kind of pinching sensation as well. This pinching sensation is one that I tend to back away from pretty quickly if it shows up in any yoga poses. And because compression could also put collapsing pressure on blood vessels and nerves, if you start to have an unusual pressure sensation in the joint, or start getting numbness and tingling downstream from the compressed area, that is another good indication to release out of the pose a bit.

The hip joint, especially the front of the hip, is one of the main areas to watch out for this.  Poses like Lunge pose and Pigeon pose are two regularly practiced poses where you’d want to be alert to unusual pressure, numbness or tingling kinds of feelings in the front leg. The good news is that if you do experience compression sensations, propping up just a bit higher could completely relieve the more worrisome kind of compression that could lead to injury. As an example, if you normally do Lunge pose with your palms flat on the floor, coming up onto your fingertips or, even better, onto a pair of blocks, might slightly open the front hip joint and relieve the compression. The same thing goes for Pigeon pose; by setting yourself up on folded blankets, with a block or a bolster under the front leg sitting bone, you can probably relieve compression in the front hip joint.

Lunge Pose using Fingertips

Other joints may be less likely to experience compression, but one that I watch out for is the front leg in Triangle pose (Trikonasana) and Pyramid pose (Parsvottanasana) at the back of the ankle joint. This is especially likely to pinch if the feet are too far apart. If the knees are generally healthy, compression of the back of the joint, such as in Child's pose, is not usually an issue for most students. 

Another place that painful compression is often experienced, especially by male students, is in the shoulder joint while doing Upward Bow pose (Urdva Dhanurasana).  Many men have limited flexion of the arm bone at the shoulder joint, and when they follow typical instructions to keep the elbows in while coming up into Upward Bow, they are unable to fully straighten the elbows, not because of elbow issues, but because the back of the shoulder joint experiences a painful compressive pinch.

It is important, as you master the basic yoga poses and begin to try out some of the more challenging poses, to take your time and notice where you feel sensation while in the postures. By once again focusing on mindfulness in your poses, you are more likely to notice poses that are not feeling “right” to you, so you can bring this to the attention of your teacher for recommendations on how to modify properly. Be patient with yourself, allow for slow steady progress in the mastery of your poses, and you will begin to discern the differences between tension in a muscle and compression around a joint.