The definition of fascia is still being debated by people much smarter than me. There is a change starting to happen in the description of fascia though. It is starting to get a broader definition.

More accurately, the idea of the “fascial system” is becoming more broad, while the definition of “fascia” is still being worked on.

The fascial system generally includes most of the connective tissue in the body: tendons, ligaments, epimysium (covering of muscles), the tissues between the skin and the muscles, nerve and blood vessel sheaths. It can be said that each of these connective tissues are part of the fascial system, but are not necessarily “fascia.” When I talk about fascia, I’m referring to the fascial system, not the strictest definition of fascia.

The Fascial System

The fascial system, and how I use the term “fascia,” includes the thick, honey-like fluid (ground substance or interstitial fluid) between the fibers and cells of the body. This fluid is capable of cushioning tissues, but also allows for the gliding of tissues along each other. When the fluid starts to “dry out”, it becomes even thicker (more viscous), making the tissues feel stiffer or restricted due to their reduced ability to glide. The fluid responds to temperature by thinning out, just like what would happen if you started to heat honey.[1]


Most commonly, fascia refers to the fibers, mostly collagen and elastin, of the connective tissue. Fascia connects and separates all cells in the body. It transmits forces from the muscles via the tendons and the epimysium. Some fascia has a proprioceptive role, which helps you feel where you are in space and helps with things like balance. Although unproven, many clinicians believe the fascia plays a role in memories in the body. In addition, fascia also creates spaces for all of the fluids between the cells (interstitial fluid) to move around and nourish the cells.

1. This is a possible explanation for why warming up makes you feel looser than first thing in the morning when your body temperature is still low. ↩︎


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