Author: Catherine Turnbull
Artist: Rida Mughal
Editor: Emma Last
Scientists are now uncovering more about one of the largest tissues in the body – fascia; the connective tissue that hugs and shapes our insides. Fascia frames many aspects of our body’s intricate internal structure, consisting of a white layer of connective tissue found under our skin, holding our internal organs and muscles in place. Once previously overlooked during dissections, the fascia was cut away by anatomists to reach the more well researched organs. Only now are we discovering that it’s more than a support bandage that cradles our insides – it plays a vital role in promoting the fluidity of our movements and healthy healing after exercise. But when exposed to infection and inactivity, it is also associated with inflammation and pain…
Our body’s intricate array of nerves, blood vessels, tendons and muscles are all held together by a layer of fascia. This vast network of connective tissue is more susceptible to pain compared to muscles and is highly sensitive to tension and stress. Fascia is made up of a type of skin cell known as a fibroblast, as well as white blood cells which make up part of the immune system. Fibroblasts produce the extracellular matrix (ECM) within fascia, which contains collagen and elastin fibres that help cells attach to this suspended connective tissue. Moreover, fibroblasts are in charge of promoting healing in response to tissue damage and regulating inflammation levels. Hyaluronic acid lubricates the layers of fascia, by binding to water molecules, enabling them to glide easily over each other. Healthy fascia is smooth and slippery, sliding and stretching with every movement you make, unlike the rigid, drier, and unhealthy form of fascia. With less hyaluronic acid, the fascial layers become adhesive and the extra forces applied stimulate the pain receptors. It is thought that unhealthy, rigid fascia can be related to poor diet, lack of exercise, bad posture, dehydration, stress, and inadequate sleep.
Damaged and unhealthy fascia can leave many people with debilitating chronic pain conditions. Myofascial pain syndrome falls under this category whereby patients experience, in some cases, unbearable long-term pain within their muscles and fascia. This disease can flare up in patients after being diagnosed with COVID-19. It is thought that COVID-19 infection causes psychological stress which can trigger pain receptors from lack of movement in our fascia after extended periods of bed rest. Moreover, the cause of this muscle pain might be associated with mass activation of the immune system, causing inflammation induced by the infection. An immune signalling protein, known as Interleukin 6 (IL-6), is produced by fibroblasts in fascia. This can induce muscle aches and pains that are associated with the more severe form of COVID-19 infections. Moreover, ‘long COVID’ can result from overly sensitised pain receptors, leading to the chronic muscle aches associated with this condition.
Inflammation in our fascia can also cause fibromyalgia: a long-term chronic pain condition associated with muscle pain all over the body. Due to muscle pain being the primary symptom that patients experience, this was thought to be the underlying cause for many years. However, it wasn’t until the last decade or so that fascia was found to play a role. Fibroblasts in fascia contribute to wound healing following tissue damage. However, if not enough growth hormone is produced from a lack of deep sleep, this leads to reduced muscle repair, causing inflammatory immune cells to damage our fascia. This in turn prolongs the activation of fascial pain receptors which can lead to the formation of more pain receptors, increasing our sensitivity to pain. A stiff, frozen shoulder is also associated with inflammation, where the fibroblasts in fascia change into myofibroblasts, which are often associated with a stiffer ECM. This reduces the fluidity of our fascia. Moreover, myofibroblasts then signal for the conversion of more fibroblasts by releasing the protein called transforming growth factor beta (TGF-β). This causes a vicious cycle of more inflammation and increased stiffness in the ECM, and ultimately, our fascia.
Aside from long-term conditions, fascia tension can also cause short-term discomfort, particularly after exercise. ‘No pain, no gain’ also references the tenderness that occurs from injury to our fascia – a painful reminder after we exert ourselves at the gym. This causes the ‘delayed onset muscle soreness’ that we feel the next day after a workout. But how well our fascia can repair itself after damage from strenuous exercise depends on our sex hormones – leaving women more vulnerable to the damaged fascia. The sex hormone estrogen plays a role in promoting collagen synthesis within the ECM, but women who have gone through menopause experience a decrease in this hormone. This hinders their collagen repair after exercise compared to women post-menopause taking hormone replacement therapy. Despite this, younger women, who have not gone through menopause, experience a reduction in collagen synthesis after exercise when taking synthetic female sex hormones, compared to women of a similar age who were not. These sex hormones include estrogen and progesterone found in the oral contraceptive pill. This difference was attributed to a lack of insulin-like growth factor 1, a protein responsible for stimulating fibroblasts to make more collagen in the ECM. These studies suggest that age influences how fascia can repair itself and, depending on the abundance of endogenous estrogen, synthetic estrogen may hinder collagen repair in women after exercise.
Although we can damage our fascia from lack of use, bad posture, or excessive and strenuous exercise, there are things we can do to reduce the chances of our fascia becoming inflamed. Stretching exercises have shown to reduce fascia pain in the heels of patients with plantar fasciitis, whereby stretching reduced pain and improved gait. Moreover, using foam rollers with compressive force on stiff muscles has gained popularity over the years by helping elicit fascial sliding. This helps stimulate self-myofascial release from the stiffened fascia after excessive exercise, promoting ease of movement within our fascial layers. Also, getting a good night’s sleep cannot be underestimated when it comes to fascia fitness. The relationship between sleep and chronic pain conditions is a complex one, with sleep deficit associated with hyperalgesia (a heightened sensitivity to pain). Insomnia is a risk factor for developing myofascial pain syndrome, possibly due to the influence sleep has on the healthy functioning of our immune system as well as allowing our bodies to mend and rest. Finally, limiting stress will prevent stress hormones from inducing an inflammatory response within the body which is beneficial for your overall health. We are only just beginning to understand more about the tissue that shapes us, with so much to learn about how fascia can influence many long-term health conditions. There are various things we can incorporate into our daily lives to aid in supporting our internal architecture. A good stretch goes a long way, ensuring that we keep our fascia moving and maintain its healthy composition. Following a healthy diet and lifestyle, including managing our stress levels and exercising ensures that we won’t lose the effortless movement of our fascia. Moreover, a good night’s sleep after an injury is necessary to ensure that our fascia can repair efficiently, without leading to inflammatory pathways that can cause overly sensitised pain receptors. Understanding more about fascia could lead to better surgical procedures that reduce pain post surgery by limiting surrounding damage caused to fascia. Finally, although we cannot always avoid illness, learning more about this once overlooked tissue can help us understand and treat chronic conditions associated with fascia that millions of people deal with on a daily basis.