It is connective tissue fibers, primarily collagen, that form sheets or bands beneath the skin to attach, stabilize, enclose, and separates muscles and other internal organs. Fasciae are classified according to their distinct layers, their functions, and their anatomical location: superficial fascia, deep (or muscle) fascia, and visceral (or parietal) fascia.

Fascia is critical because it actually helps to create the shape of our bodies. Basically, fascia is like a very thin wet suit just under the skin that wraps around each individual muscle and keeps everything in place (including our organs). It’s that thin white stringy layer that you see on a chicken breast when you’re cooking.

When it’s healthy, it’s like clear saran wrap. But injuries, stress, bad posture, emotional behavioral patterns, and poor body maintenance can cause the fascia to get tight, dense, short, and plasticized. This further restricts movement and the alignment and efficiency of the body can be compromised, trapping toxins in the fascia and leading to thicker ‘pockets’ throughout the body—such as those that often form around the waist.

Like ligaments, aponeuroses, and tendons, fasciae are dense regular connective tissues, containing closely packed bundles of collagen fibers oriented in a wavy pattern parallel to the direction of pull. Fasciae are consequently flexible structures able to resist great unidirectional tension forces until the wavy pattern of fibers has been straightened out by the pulling force. These collagen fibers are produced by the fibroblasts located within the fascia.

Fasciae are similar to ligaments and tendons as they are all made of collagen except that ligaments join one bone to another bone, tendons join muscle to bone and fasciae surround muscles or other structures.

The good news is that fascia is malleable and can be repaired—and foam rolling and bodywork are both fantastic ways of releasing all those unhealthy toxins from the fascia and helping to reduce thickness in the body.

Fasciae are normally thought of as passive structures that transmit mechanical tension generated by muscular activities or external forces throughout the body.

The function of muscle fasciae is to reduce friction to minimize the reduction of muscular force. In doing so, fasciae:

Reduces friction between muscles, allowing sliding.[citation needed]
Suspend organs in their cavities.[citation needed]
Transmit movement from muscles to bones.[citation needed]
Provide a supportive and movable wrapping for nerves and blood vessels as they pass through and between muscles.[5][need quotation to verify]