The soles of our feet, which support our entire body, feature an intricate arch that is not merely the shape of bone. It is a mirror reflecting how solid the qi of the kidney—the root of our body—and the spleen—which governs the muscles—truly is. In the Donguibogam, the feet were regarded as the root of the body. Just as a tree stands straight only when its roots are sturdy, the text explains that when the arches of the feet collapse, the balance of the entire body breaks down.
In particular, the muscles and ligaments supporting the arch of the foot are deeply connected to the qi of the spleen. The spleen strengthens our muscles, absorbs nutrients from food, and produces qi and blood. If the spleen qi weakens, the muscles of the soles lose strength, and the arch sinks as if caving in, much like a foundation softening in muddy ground.
On top of this, when there is a deficiency in the kidney qi, which governs our skeletal system and essence and marrow, even the bones and ligaments grow fragile, accelerating arch collapse. Struggling to stand or walk for long periods and feeling an aching pain on the inner side of the ankles can be signals of this deficiency in the spleen and kidney. Just as a roof shakes when the pillars of a house weaken, when the kidney—the root of the feet—and the spleen—the foundation of the muscles—become deficient, it affects not only the feet, but also the knees, pelvis, and spine, leading to whole-body pain and fatigue.
Furthermore, when dampness accumulates in the body, the feet feel heavy and swollen, further worsening arch collapse. The Donguibogam advises that prolonged exposure to cold qi or damp environments, or the buildup of dampness-phlegm from a weakened digestive system, can hinder circulation in the soles and reduce the supporting strength of bones and muscles, causing the soles to tire easily and ache. For this reason, we must attend not merely to the feet, but to the balance and communication of the entire body.
