Let’s blur the distinction of individual muscles in isolated action, and see another design in the fibers. The individual fibers that make up all musculature lay along diagonals. Most of the discreet muscles also lay along diagonals. What begins to appear, if one gives up the idea of isolated muscle groups and allows muscles to transit boney structures is a pattern of diagonal lines.12 Crossing spirals of muscular fiber become apparent. For example, a left pectoral muscle blends with a right intercostal that joins an oblique muscle that blends into a gluteal muscle.13 This is exactly countered by a matching helix (a spiral in 3-dimensions) from the right pectoral on down. Start at another point and the same type of helix emerges. An iliacus leads to a quadratus lumborum that wraps into the lattissimus on the other side of the body and so forth.
This comparison to weaving is in line with Snelson's conception of tensegrity. Ohlgren continues,
Bones... assume a structural dimension that is in addition to levers and to spacers inherently more in tune with a tensegrity view of the body’s mechanics. With the use of a couple of analogies, this new model can be appreciated. A machine that is designed for a consistent relationship to gravity is liable to sustain serious damage when forces outside its design-frame are applied to it. If this were indeed our design, few of us would survive our childhood in working order. Try putting a computer through the innumerable crashes of a typical youth and imagine what working order it might be in, to say nothing of its appearance.
To what do we owe our remarkable resilience? From football, to skiing, to tumbling we are able to sustain a tremendous array of reckless experiments and live to tell about it. Although our muscular tube design is not precisely an interweaving of diagonal fibers, as in a basket, the basket-weave analogy is helpful...
For a certain generation this might bring to mind the straw “Chinese handcuffs”. These were tubes of woven straw which expanded when compressed and contracted when elongated, allowing one’s fingers to enter the tube from both ends but preventing the withdrawal of the fingers when they were pulled away. After either compression or elongation or twisting, the spiral double helix weave pattern will always return to its original shape by its own momentum. This model is closer to a spring than a lever/pulley model and reflects our spring-like resiliency.
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