This week’s question is about twists and digestion.
Here’s my response:
In my experience, from strictly a practice and personal experience (mine and my peers’) perspective — so not based on theory or scientific study — is that it depends on where you are in the digestive process, which twists are done, and which direction they’re done to first.
Compressing the abdomen while matter is in the stomach or upper small intestines will NOT aid digestion and instead produce heartburn and indigestion — particularly closed twists like Marichyasana 3 and deep forward bends where the thighs compress the abdomen (including Malasana and Balasana). At this stage of digestion, doing a closed twist to the right, for instance, could also squeeze the bile duct, which is already active and force excess bile into the stomach (leading to heartburn). Those same compressions can and often do help once material is lower down in the digestive system.
Open twists, particularly supported variations of standing poses like Parsvakonasana are excellent for expediting the movement of matter from the stomach and upper small intestines to the bulk of the gut and subsequently also into the LI/colon. This is especially true if you pay attention to which side of the abdomen is compressed or opened first: Parsvakonasana to the right compresses the ascending colon, and “opens” the descending colon. That is true whether doing the Uttitha “open” version of the twist or the Parivritta or “closed” version of the twist — it’s one of the reasons why we do standing poses to the right first and then to the left, and why teachers who “mirror” regularly can develop digestive problems if their practice doesn’t balance that out prior to teaching.
I also find that Supta Virasana and mild supported back bends where the legs and pelvis are below the head and thorax are best for the entire digestive process, from initial breakdown to absorption to elimination. You can promote either faster elimination (but less will be absorbed) or better absorption (but slower elimination) by whether you choose lateral or linear supported poses.
Inversions, even partial inversions are thought (and again in my practice I’ve found it to be true) to aid absorption, but slow elimination to some degree. That said, I can see how they could help constipation by decompressing the intestines and any blockage that may be there (like if your toilet is clogged, no matter how much more you put in there it won’t speed up drainage — you have to remove the blockage first), and I’ve used them for students for that effect with positive result. Inversions in this case don’t have to be full headstand or shoulderstand, but can be partial like supported or hanging downward dog, or supported Setu Bandha Sarvangasana. Just don’t do inversions until the material is no longer in the stomach 😉