We are literally surrounded by the stuff. Matrix-like, it wraps around all 600 muscles in the body connecting them to each other and to our bones.
Yet fascia, the most plentiful tissue in the human body, remains a medical mystery.
A new paper published in the Journal of Bodywork and Movement Therapy points out that even the interpretation of fascia is debated.
"The definition itself of the fascia is not consistent in a variety of authors," the authors say.
In addition to this, relatively little research has been done to determine its function.
"Fascia is like the Cinderella tissues of the body," Tom Myers, a leading thinker in integrative anatomy and author of Anatomy Trains, told The Huffington Post.
"It has been the most ignored of all the tissues in the body - at least up until recently. Yet, fascia is critical to understanding the body and what it takes to keep your body functional and healthy all life long."
But, even this is arguable, with many anatomical texts showing the body stripped of fascia and many scientists denying it has a function beyond wrapping paper for our muscles.
Alternative practitioners however are obsessed with the therapeutic possibilities of working on fascia to treat pain, injury, misalignment and to relieve tension.
The discrepancy between alternative therapists and some in the science community lies in the fact that proving therapeutic efficacy is a challenge.
"There are very few home runs within the realms of manual therapy, full stop," explains Bill Adamson✓, spokesman from Osteopathy Australia, an allied health profession. "In fact many techniques that are widely used have very little acceptable literature behind them.
"No matter the results seen in private practice, these techniques are often difficult to replicate in the laboratory. "
Whether scientists recognise the significance of fascia depends on how "holistic or reductionist" they are, says Simon Borg Olivier, a lecturer in Integrative Applied Eastern Anatomy and Physiology at RMIT University.
"Fascia is one of four energy moving systems. There's the cardiovascular system, the nervous system, the lymph system. They're all equally as important," Borg Olivier says.
"Fascia can conduct electrical energy, which is the root of the meridian system, [but] people don't understand the concept of energy medicine. It's a hotly debated topic."
Hotly debated, but nevertheless worthy of our attention.
Wallace Sampson, alternative medicine sceptic and professor emeritus at Stanford University told Gawker's science site io9: "Most scientists, even those wary of alternative therapies, admit that the field of fascia research is a field of neglect, and remains sorely under-investigated."
As researchers devote more time to understanding the importance of fascia, there is some consensus about this fibrous collagen.
"From what all the evidence indicates there is no one technique that will fix all conditions, one cannot just treat just one element of the body," says Bill Adamson. "The human body is a dynamic, versatile, adaptable organism; if a practitioner just treats neural structures and ignores the blood that supplies the nutrients, or the muscles that provide the movement, or the bones that provide the levers then they are not treating the whole system.
"Fascia is an incredible aspect of human anatomy ... However for osteopaths fascia is just one element of the human body.
"It does not make intuitive sense but rather makes anatomical sense that the fascia of the body would have some influence of the movement and pain paradigms of the body."
Borg Olivier agrees that any treatment of pain, injury and tightness in the body should consider how the body works as a coordinated whole.
"Fascia is not the be all and end all of how the body works," he says.
"Don't just isolate the body ... appreciate the whole body is a holistic structure. Everything is connected."
- Sydney Morning Herald