Muscle strength depends on muscular tissue. The human body has more than 650 muscles, making up 40% of the body's weight.
Muscles are made up of cells intertwined by a connective tissue that acts as a support. This tissue, rich in collagen, is one of the main constituents of muscle. It creates a sheath around muscle fibres providing support and protection. Indeed, collagen is an integral part of a system that links muscular cells together and group them. This anchoring system allows muscle cells to adapt to the mechanical distortions they undergo during contraction. Given that the aging phenomenon leads to a reduction in the production of collagen, external and internal links between muscle cells are also reduced, causing deterioration and weakening of muscles as a whole over the years. This situation affects muscle tissue and reduces its capacity to carry out its essential functions.
One of the diseases related to a reduction of collagen in muscle is fibromyalgia. Its diagnosis has been erroneous for a long time due to a lack of knowledge concerning the underlying pathophysiology of this disease and the lack of specific biochemical markers to diagnose it. Although the exact causes of this desease remain unclear, research conducted at the American College of Rheumatology and involving various samples (muscle biopsy, urine and blood test) showed disturbances in collagen metabolism and structure in people with Fibromyalgia.
These disorders are reflected in some cases by a lower amount of intramuscular collagen as well as by a remodeling of the extracellular matrix, with collagen deposits being found around the nerve fibers. This results in a lower threshold for muscle strain (structural and mechanical aspects) and a lower tolerance for pain in sensitive areas (nervous aspect). In a clinical study conducted in a small group of people suffering from fibromyalgia for 2 to 15 years, it was found that taking a "hydrolyzed collagen" significantly lowered the average level of pain; this effect being quite significant in a subgroup of participants.