Twists are quite different from the flexion/extension movements involved in forward- and backbends, because twists create strong but evenly distributed compression of the intervertebral discs as a side-effect of the twisting action, whereas forward and backbends strongly compress either the front or back edge of the disc, but not the opposite edge. The evenly distributed compression is why twists are so beneficial for long-term spinal health.

Any twisting action in the torso is created by diagonally oriented muscles in the torso. As they contract, they not only twist the torso, but they also compress the trunk vertically, and with it, the spine. (If this is not intuitive to you, take a towel and twists it, and notice how it shortens.) The shortening caused by the spinal twist compresses the intervertebral discs, which stiffens up the discs and hinders further rotation of the torso. Because of the inhibiting consequences of this spinal compression, lengthening the torso (and thus the spine) is an integral part of going deeper into any spinal twist.

However, the compressive effects of spinal twists are not merely a slightly annoying side effect. The compression of the discs is actually tremendously beneficial to spinal health. Over a lifetime, the main cause of spinal problems is degeneration of the intervertebral discs, which manifests as a shrinking and drying out of the discs. How do you keep your discs healthy long term? Keep them supplied with nutrients and flush out waste products by mechanically pumping the discs.

Intervertebral discs contain living cells which maintain and repair the intricate structure of the discs. However, these living cells require an ongoing supply of nutrients and oxygen for survival and to do their work, as well as the removal of metabolic waste products. Since the discs have no blood supply after the age of 25 or so, and simple diffusion of materials in and out of the discs via the adjacent vertebrae is insufficient, alternately compressing and extending the spine creates a pumping action that helps move waste products out of, and nutrients into, the discs. For longterm spinal health this pumping action is the best technique, and twists are the best way to create that pumping action because they are safe and effective. In comparison, the extreme one-sided compression of the disc typical of forward bends can lead to herniated discs, which are a main cause of back pain (and can contribute to disc degeneration). Spinal twists are a much safer way than forward bends to compress the discs, as during spinal twists the discs are evenly compressed front, back, and sides, which avoids the potential for disc ruptures caused when only one side of a disc is compressed.

In addition to the benefits to the intervertebral discs, the compression in the torso that is caused by spinal twists is also very beneficial to the internal organs and their associated glands. Like the spinal discs, the internal organs and glands are squeezed by the twisting motion of the torso. This squeezing action has a cleansing and stimulating effect on the abdominal organs, reducing stagnation and keeping them functioning optimally.

Try it now: Come to a comfortable seat on the floor (or a chair), and align your spine in its natural S-curve. I intentionally do not say “straighten your spine,” when I want a neutral spine, because a straight spine is not the same thing as a neutral S-curve, and in most situations we do want the spine in its neutral S-curve, not in a straight line. However, the one time that we do actually want to straighten the spine is in spinal twists, because when we lengthen the spine we end up straightening it by necessity, and thus create two positive effects at once:

1. The lengthening of the spine reduces the internal pressure of the discs, and this pressure reduction, in conjunction with the pressure increase during the twisting action, creates the pumping action that increases the nutrient exchange in the discs.

2. The straightening of the spine that accompanies the lengthening of the torso realigns all the intervertebral joints more closely to the plane in which the twist is happening (the transverse plane) and the more the discs are aligned with the plane of twisting, the more evenly the pressure created by the twist will be distributed throughout the discs, keeping them safe.

Inhale your left arm up while engaging your deep core muscles (transversus abdominis) to pressurize your abdominal cavity and thus lengthen the spine and flatten its natural S-curve. As you exhale, lower your left hand to the opposite knee as you bring the right hand behind you, initiating the twist from the base of the spine. With each subsequent inhale, re-lengthen the spine, making sure to avoid any forward bending to evenly distribute the compression to all parts of each disc. With each subsequent exhale, deepen the twist, gently and evenly increasing compression, spiraling up from your left hip to your right shoulder blade. As you alternately compress and decompress the spine, visualize waste products being expelled from the discs during exhalation, and nutrients dispersing into the discs during inhalation. After 5-10 breaths, return to center on an inhale, and repeat on the other side.