According to the Chinese medical classics, the Kidney grasps the Lung Qi on inhalation. When I first heard that back when I was a student, I didn't understand how this could be. How could two organs who are not even touching each other be connected in this manner?
After learning more about Five Element Theory, Qi movement between the organs and other key components of Chinese medicine, I began to understand that the Kidney does indeed grasp the Lung Qi on inhalation, even though I couldn't understand the anatomical mechanics of how this occurred....until recently. It dawned on me this year when I was seeing the same patterns in many patients, likely due to the stress from the pandemic.
The actual Kidney organ doesn't reach up and pull down the Lungs on inhalation, but the muscles do.
Before I go any further, this image is not my favorite illustration but it was the best that I could find. The iliopsoas muscle is comprised of the psoas minor, psoas major and iliacus muscles. The top portion of the psoas major and minor muscles intertwine with muscles fibers in the diaphragm muscle. The diaphragm muscle greatly affects our ability to breathe deeply. When we take a deep breath, this muscle must be drawn downwards in order to give the lungs plenty of room to expand and inhale more oxygen. The psoas major and minor are located close to the Kidneys, which leads me to think that this is what the Chinese medical classics meant about the Kidneys grasping the Lung Qi on inhalation. The organ itself isn't drawing the breath downward, but the soft tissue structures near the Kidneys are playing an important role in breathing deeply.
The next time you take a deep breath, think about your breath going downwards rather than thinking about your abdomen going outwards, which is what is often taught. Your abdomen, ribs and back muscles will likely expand when you take a deep breath, but focus more on pulling the breath downwards on an inhale and releasing it upwards on an exhale.