When toward the end of a yoga sequence we move into seated and reclining twists, the benefits are often obvious. We tend to feel calmer and more centered; it’s a pretty universal experience. In fact, I’ve never heard anyone say, “Twists make me really nervous!” (Well, unless they’ve had spinal injuries or surgeries—in which case a more cautious approach is important.) But we may hear in our yoga classes some odd, even potentially dangerous, misconceptions about twists that need to be retired.
Although popping or cracking doesn’t mean anything is breaking (and when it happens occasionally there is no cause for concern), it can be overdone. Our joints contain fluid and gasses. When we put pressure on a joint, the synovial fluid is forced to separate due to the increased pressure within the joint, forming a cavity or “gas bubble”; it is the sudden creation of the cavity that produces a cracking noise. Popping our joints can become a habit, perhaps because doing so stimulates the Golgi tendon organs and thus causes the surrounding muscles to relax, creating a sensation of relief. However, popping a joint may be a bad habit to form because, while the evidence is not yet definitive, some experts believe that frequent self-adjusting of the spine can damage the joints, and popping the knuckles has been found to correlate with swelling in the hands later in life. Fortunately, gentle and lengthening spinal twists without added tugging or pressure can bring relief without bringing in the percussion section and the possible risks of popping our joints. If you feel as if you need to push yourself into a deep twist to adjust your back, that feeling may indicate an underlying issue, so seeing a chiropractor or a physical therapist may be a good idea.
The big vertebrae in the lumbar spine (lower back) have little to no rotational capacity. I observed this for myself during a yoga-focused cadaver anatomy course, which was part of a teacher training that I led. When our anatomist showed us the incremental amount of rotation possible for those big spinal bones, my students were taken aback. As they learned then, the revolving sensation we feel in the lower torso during a twist comes from the stretching of muscle and connective tissue, not from rotating the lumbar spine.
So, in your practice, when you hear suggestions about lengthening the spine (axial extension) on the inhalation and revolving on the exhalation, listen up. That axial extension encourages the twist to move upward to the smaller, more mobile upper vertebrae (and the very mobile shoulder blades), and that is the part of your spine that can rotate. We don’t need to destabilize the lower back, sacral joints, and pelvis by attempting to twist our lumbar spines. Keep your twist in the upper body, which can actually gain and benefit from increased flexibility.
Twisting is a natural and healthy movement of the spine, and regular twisting is essential to keep the vertebrae strong. Restricting the movements of our backs can make performing daily tasks increasingly difficult and can increase our risk of falling because core immobility can make us unable to right ourselves. However, despite their benefits, people with osteoporosis may worry that twists are unsafe for them; in fact, if practiced with care, some gentle twists might be quite beneficial. The tricks to twisting safely if you have osteoporosis are to engage the core during twists—you can make sure to do this by practicing only gentle seated twists that require muscular engagement rather than allow the abdominal muscles to remain passive—and to avoid manually forcing the spinal column into a twist position. For example, practice a seated twist with your arms in a goalpost position to make sure you revolve mainly in your shoulders and upper back and do not force the spine to twist; maintain a long spine and be sure to engage your low belly.
Carol Krucoff, who teaches the Yoga for Seniors program at Duke Integrative Medicine, has been quoted as saying, “Rotation is an important movement for flexibility and function, and I do not advise those with compromised bone to avoid twists. Rather I follow the National Osteoporosis Foundation guidelines in cautioning against ‘twisting of the spine to the point of strain’ and encourage students with osteoporosis to avoid extreme twists, to keep rotation in the mid-range and use a gentle quality of motion.” I would contend that if you are unsure about damaging weakened bones, these are good rules to follow, but do let your body move; it likes movement.
While B.K.S. Iyengar was a strong proponent of the “squeeze and soak” idea of wringing out the organs as if they were dirty dishrags, there isn’t a lot of anatomical support for the claim. Amy Matthews, co-author of Yoga Anatomy, writes that “the concept of the ‘squeeze and soak’ action is not that accurate,” but she acknowledges that twists do have an impact on our organs: “Twists do affect our mobility (movement of organs in relation to each other) and our motility (movement within an organ). However, a number of factors are involved in stimulation of our organs.” Similarly, Yoga International editor Kat Heagberg has laid the “liver detox” myth to rest while noting that twists benefit the organs: “Your liver is not a dirty dishrag. It’s a liver. And it has its own natural detox process, which is largely a cellular process. This doesn’t mean spinal twists are utterly useless as far as your organs are concerned, though. While you can’t negate excess jello shots with a few extra ardha matsyendrasanas the next morning, twists are still an important part of a balanced practice and they do improve circulation, which is quite beneficial to your internal organs. But you’re not actually ‘squeezing out’ your liver every time you do parivrtta trikonasana.”
So, what is the truth about twist poses? They stimulate circulation, build heat, and release tension in the muscles of the spine. They increase the mobility of the abdomen and rib cage by softening fascia, and twists can also stimulate the many vagus nerve fibers in the torso and neck (the cranial nerves that calm the visceral organs), which could explain the “ahhh” effect twists can have—the feeling of relaxation and release that they give us. It is my firm, though unproven, belief that, if we take time to twist our bodies, we will untwist our minds. Plus, twists are often among our favorite poses, and when we are happy in our movement, we move more often, and that’s rarely a bad thing.