Yoga Twists, fascia, DNA, the diaphragm

Twists in yoga set up a rotation in the body by using a combination of opposing forces. They are hugely beneficial for cleansing the body of toxins and for flushing blood through the organs. The spine can roughly be divided into three parts, the neck, thorax (rib cage) and the lumbar (lower back).
The vertebrae in the rib cage are designed to rotate. The vertebrae in the lumbar are designed to flex and extend. The vertebrae in the neck are designed to do both.

The junction between the ribs and the lumbar is the most mobile part of the mid back. That is where most twists gain their maximum leverage. That junction (T12 / L1) lies right behind the diaphragm and between the kidneys. The diaphragm covers the stomach, important nerves to the abdomen, the gall bladder, liver, the kidneys, the spleen and a collection vessel for lymph glands. The major organs like the liver, kidneys and spleen act as a huge reservoir for blood.

Imagine when you are doing a twist that you are doing a liver squeeze, or that you are bringing your kidneys round or lifting them. It is like squeezing a sponge over the bath and filling it again with fresh water. Healthy kidneys for instance, can pump 1.2 litres of blood in a minute. You might notice after a good yoga session that your urine is darker or more in volume. That is the flushing action of the twists.

There is however a much wider benefit to twisting. Have you ever carefully examined the fibres of a rope?
Not only the main strands are twisting but also the fibres within the strands. A twisted rope is stronger than the individual fibres. The design of the human body uses the same principles to increase strength. Let me give some examples. Your pectoral muscles run from the where the first six ribs anchor to the sternum into the front of the top of the arm bone (the humerus). The insertion lies right next to the insertion of latissimus dorsi and teres major. Both pectoralis major and latissimus dorsi insert into a very small area by twisting the fibres at the last minute. That hugely increases the strength of the muscles as a whole. Another example is the achilles tendon. The achilles connects the calf muscles, gastrocnemius and soleus into the heel bone (the calcaneus). If you examine the fibres closely you find that they are twisted like a rope. Another example is the uterus. When contractions start how does the uterus force the baby down into the small pelvis through the cervix? First of all it sets up a battering ram known as "the waters". They open the cervix and cushion the head. If a well intentioned obstetrician breaks the waters too soon the head becomes the battering ram. The muscles of the uterus itself are twisted so that when the contract the head is forced downwards taking the body with it.

Finally let's think on a microscopic scale. Looking at the structure of DNA under an electron microscope you will see a double coiled helix structure. The human body itself is built on a foundation of a twisted rope. Even water going down a plughole forms a vortex or twisting action. I have always wanted to test which way the water goes down the plughole in the Southern hemisphere compared to the Northern hemisphere. As a boy I used to stir the bath the opposite way to see if I could persuade the whirlpool to twist the other way. I used to canoe with a friend down the Serpents Tail at Llangollen in North Wales. Once when I was following him he disappeared down a hole. He said later that he saw his kayak twisting down the whirlpool ahead of him. It is a wonder that we reached adulthood.

By setting up twists in yoga using opposing forces you increase the strength of individual muscles.
I use this principle when I am treating someone with an injury, the shoulder for instance. Sometimes the fascia constricts around the muscles and squeezes them into a tight space. They cannot fully stretch. By raising the arm and twisting you can unwind the fascia. You could use that principle in a class. Don't ask the class to simply raise an arm in Utthita Parsvakonasana for example. Ask them to swing the arm in front of the body then upwards. It is much easier because it unwinds the fascia in the shoulder.