Well, actually there is no such thing as a muscle knot, what we feel and think is a knot are areas of tension in our muscles or tight tendons or ligaments producing tension in our muscles. For example, many people talk of having and being able to feel small “gnarly, crunchy, stringy” areas at the top of the shoulder blade, when very often this is some of the tendons of the shoulder muscles under tension.
So what causes this? Our muscles are made up of lots of tiny muscles fibers and in the case of these gnarly, crunchy areas, it is the muscle fibers that have contracted (shortened) as a result of physical activity, postural imbalance, or stress and then they stayed shortened and can build up and become chronic (permanent).
When muscle fibers contract they become shorter, fatter and bunched up, and this creates a physical squeeze on the circulation in the area. Vital supplies of fuel for the muscles in the form of oxygen and nutrients from the blood are reduced, and the removal of noxious waste products by the lymphatic system becomes less efficient. The result? Muscles that become exhausted, irritated, possibly inflamed, and painful.
This is the start of a vicious cycle - the pain and spasm cycle. When we feel pain, our muscles contract, and contracted muscles cause more pain. So our muscles contract further, there's more pain, and so it goes on.
Over time, if not addressed, chronic muscle tension causes other changes in the muscle tissues, which become stiff and hardened (and sometimes stuck together), a process called fibrosis. These small areas of bunched, hardened muscle fibres are those hard, crunchy, tender areas that I find as I massage or as you rub your own sore shoulders or calves.
Plus, sometimes nervous system involvement will add another layer of pain, as palpable nodules of contracted muscle tissue become what are known as Trigger Points, which can refer pain to distant parts of the body.
As a Sports Massage and Remedial Therapist this is all in my day's work. This kind of soft tissue dysfunction is what Massage was created for. Chronic muscle tension, fibrosis and Trigger Points respond fantastically well to the right kind of massage!
If you have any questions or comments on the above then please let me know.