There are two prominent outer layers to our energy fields – each encircles the entire body and function different. One is at arms length, the other halfway between full extension and the body.
Somewhat like the eyes, the outer one extends out to “read” our environment and relays back to the inner field what is being sensed. The inner field translates the potential levels of harm to the body. If operating in a healthy way, along with brain, one can appropriately respond.
Simplistically, in Chi Kung (Qigong) both fields are cared for through a combination of visualization and/or body gestures for cleansing and nourishing purpose. You learn to distinguish both and easily move your awareness from one to the other or hold a sense of both simultaneously.
In Tai Chi (Taiji) these fields operate as responsive levels in maintaining distance and self-defense. The outer moves you into action and the inner is strengthen in motion and in combination with the physical to ward-off an incoming force, protecting the body.