At the close of a commentary in ‘The Blue Cliff Record’, Yuanwu wrote:
Answering the monk who asked, “What is the
meaning of the Patriarch’s coming from the
West?”, Hsiang Lin said, “Sitting for a long time
becomes toilsome.” If you understand this way,
you are “turning to the left, turning to the right,
following up behind.” (1)
I can’t really speak to the exchange between the monk and Hsiang Lin, but I can say that Yuanwu’s description, “turning to the left, turning to the right, following up behind”, has been very helpful to me.
“Turning to the left, turning to the right”—stretch in the ilio-tibial bands sets off “reciprocal innervation”* of the left and right sartorious muscles, and consequently reciprocal activity in the tensor and gluteous muscles. The result is a subtle “turning to the left, turning to the right” in an upright posture, and a stretch in both the ligaments that connect the abdominals to the rectus and in the ligaments that connect the gluteous muscles to the fascia behind the sacrum and the lower spine.
“Following up behind”—the combination of stretch and resile in the lumbodorsal fascia and pressure from the “fluid ball” of the abdomen allows the vertebrae of the spine to find alignment, and permits the fascia behind the spine to provide support.
☞ PDF, A Natural Mindfulness
* Dr. John Upledger’s description of reciprocal innervation, as he experienced it lying in an isolation tank: “At some point my body began to make fish-like movements, as though my pelvis and legs were the lower part of a fish moving its tail from side to side. This movement was nice and easy. The neurophysiologist in me related these movements to an expression of what we call ‘reciprocal innervation.’ The principle here is that, when your trunk is bent to the side in one direction past a certain threshold, the muscles on the other side of the trunk contract. In doing so, the nerve impulses are diverted from the side to which you are bent, and those muscles relax. Your trunk now bends in the opposite direction until that side-bending threshold is passed. The nerve impulses are then diverted again to the opposite side, causing muscle contraction and side bending in that direction.”–“Your Inner Physician and You: Craniosacral Therapy and Somatoemotional Release”, John E. Upledger, p. 165
1) “The Blue Cliff Record” (koan 117), compiled by Yuanwu Keqin, tr. Cleary & Cleary, Shambala
publications pg 114